ODOT-Location and Design Manual Volume II -January 2015

Ohio Department of Transportation Central Office • 1980 West Broad Street • Columbus, OH 43223

John Kasich, Governor • Jerry Wray, Director

Date: January 16, 2015 To: All Current Holders of the Location and Design Manual, Volume 2 Re: Location and Design Manual, Volume Two Revisions Transmitted herewith are revisions to the Location and Design Manual, Volume 2. The following revisions have been made:

• Revisions / Additions in Red • Section 1002.1 – Additional guidance/requirements allowing a single pipe material • Section 1002.3.7 – Added SS833 • Section 1005 – Removed requirement for ODOT to secure a floodplain permit, Added

guidance regarding Flood Hazard Mapping and the ODOT Self-Permit Process • Section 1009.2.1 – Removed guidance regarding specifying a pipe material for 6”

underdrains • Table 1104-1 – Removed 33” size • Section 1105.2.2 – Removed guidance regarding burying replacement concrete box

culverts • Section 1117.2.2 – Vegetated Biofilter revisions • Figure 1117-4 Vegetated Ditch Example – Removed • Appendix A – Added forms LD-50; No-Rise Certification and LD-51; Floodplain Letter

of Compliance Template • Sample Plan Note D112; Item 611-Conduit Bored or Jacked – Removed 0.5” reference • Sample Plan Note D121; Item Special-Pipe Cleanout – Added 3 pay items

The online revisions of the Location and Design Manual, Volume 2 can be found at http://www.dot.state.oh.us/Divisions/Engineering/Hydraulics/Pages/default.aspx in PDF format. Technical questions or recommended changes should be directed to Jeff Syar (614) 275-1373 or Matt Cozzoli (614) 466-3152. Respectfully,

Jeff Syar, P.E. Office Administrator Office of Hydraulic Engineering

An Equal Opportunity Employer

http://www.dot.state.oh.us/Divisions/Engineering/Hydraulics/Pages/default.aspx

Notice

To ensure proper receipt of future revisions to the manual, please visit the online Design Reference Resource at: http://www.dot.state.oh.us/drrc/. This manual is produced by the Office of Hydraulic Engineering. Technical questions, recommended changes, or suggestions should be sent to: Ohio Department of Transportation Attn: Jeffrey Syar, P.E. Administrator, Office of Hydraulic Engineering 1980 West Broad Street Columbus, Ohio 43223 (614) 275-1373

Table of Contents (Revised January 2015)

Preface ........................................................................................................................................................... i Ohio Counties ............................................................................................................................................... iii Concordance ................................................................................................................................................. iii Glossary of Terms ......................................................................................................................................... v Design Reference Documents……………………………………………………………………………………...x

1000 Drainage Design Criteria

1001 Hydraulic Design Criteria ................................................................................................................ 10-1 1001.1 Responsibilities .......................................................................................................... 10-1 1001.2 Natural Streams ......................................................................................................... 10-1

1002 Pipe Criteria .................................................................................................................................... 10-1 1002.1 Introduction ................................................................................................................ 10-1 1002.2 General Requirements................................................................................................ 10-2 1002.3 Conduit Types ............................................................................................................ 10-2

1003 Hydrology ........................................................................................................................................ 10-6 1003.1 Estimation of Magnitude and Frequency of Floods on Ohio Streams ........................... 10-6

1004 Flood Clearance .............................................................................................................................. 10-7 1004.1 General ...................................................................................................................... 10-7 1004.2 Design Year Frequency .............................................................................................. 10-7

1005 Highway Encroachments on Flood Plains ...................................................................................... 10-7 1005.1 General ...................................................................................................................... 10-7 1005.2 Type of Studies .......................................................................................................... 10-9

1006 Allowable Headwater ...................................................................................................................... 10-9 1006.1 Design Storm ............................................................................................................. 10-9 1006.2 Culvert Headwater Controls ........................................................................................ 10-9 1006.3 Bridge Headwater Control ........................................................................................ 10-10 1006.4 Controls Specific to Flood Insurance Studies (FIS) ................................................... 10-11

1007 Pipe Removal Criteria ................................................................................................................... 10-11 1007.1 General .................................................................................................................... 10-11 1007.2 Asbestos pipe ........................................................................................................... 10-11

1008 Conduit Design Criteria ................................................................................................................. 10-12 1008.1 Corrugated and Spiral Rib Steel and Aluminum Pipes, and Corrugated Steel and Aluminum Pipe Arches ......................................................................................................... 10-12 1008.2 Rigid Pipe ................................................................................................................. 10-12 1008.3 Thermoplastic Pipe ................................................................................................... 10-13 1008.4 Corrugated Steel and Aluminum Box Culverts and Corrugated Steel Long Span Culverts. ............................................................................................................................................ 10-13 1008.5 Precast Reinforced Concrete Box Culverts ............................................................... 10-13 1008.6 Precast Reinforced Concrete Three-Sided Flat-Topped Culverts .............................. 10-14 1008.7 Precast Reinforced Concrete Arch Sections ............................................................. 10-14 1008.8 Precast Reinforced Concrete Round Sections .......................................................... 10-15 1008.9 Arch or Flat Slab Top Culvert Foundations ................................................................ 10-16 1008.10 Bridge Foundations ................................................................................................ 10-17 1008.11 Waterproofing Membrane ....................................................................................... 10-17 1008.12 Precast Reinforced Concrete Flat Slab Tops, Catch Basin Tops, and Inlet Tops ..... 10-18 1008.13 Wingwall Design ..................................................................................................... 10-18

1009 Subsurface Pavement Drainage ................................................................................................... 10-18 1009.1 General .................................................................................................................... 10-18 1009.2 Types of Subsurface Drainage.................................................................................. 10-18

1010 Maintenance of Traffic Drainage ................................................................................................... 10-20 1010.1 General .................................................................................................................... 10-20

1011 Temporary Structures ................................................................................................................... 10-20

1100 Drainage Design Procedures 1101 Estimating Design Discharge .......................................................................................................... 11-1

1101.1 General ...................................................................................................................... 11-1 1101.2 Procedures ................................................................................................................. 11-1

1102 Open Water Carriers ....................................................................................................................... 11-4 1102.1 General ...................................................................................................................... 11-4 1102.2 Types of Carriers ........................................................................................................ 11-5 1102.3 Ditch Design Criteria - Design Traffic Exceeding 2000 ADT ........................................ 11-6 1102.4 Ditch Design Criteria - Design Traffic of 2000 ADT or Less ....................................... 11-10 1102.5 Design Aids for Ditch Flow Analysis .......................................................................... 11-11

1103 Pavement Drainage ...................................................................................................................... 11-11 1103.1 General .................................................................................................................... 11-11 1103.2 Design Frequency .................................................................................................... 11-12 1103.3 Estimating Design Discharge .................................................................................... 11-12 1103.4 Capacity of Pavement Gutters .................................................................................. 11-12 1103.5 Pavement Flow Charts ............................................................................................. 11-13 1103.6 Bypass Charts for Continuous Pavement Grades ..................................................... 11-13 1103.7 Grate Catch Basins and Curb Opening Inlets in Pavement Sags ............................... 11-14 1103.8 Bridge Deck Drainage .............................................................................................. 11-14 1103.9 Slotted Drains and Trench Drains ............................................................................. 11-15

1104 Storm Sewers ................................................................................................................................ 11-15 1104.1 General .................................................................................................................... 11-15 1104.2 Design Considerations.............................................................................................. 11-16 1104.3 Layout Procedure ..................................................................................................... 11-18 1104.4 Storm Sewer Design Criteria .................................................................................... 11-18 1104.5 Hydraulic Design Procedure ..................................................................................... 11-19 1104.6 Combined Sanitary Sewer Separation ...................................................................... 11-20

1105 Roadway Culverts ......................................................................................................................... 11-20 1105.1 General .................................................................................................................... 11-20 1105.2 Stream Protection ..................................................................................................... 11-20 1105.3 Types of Culvert Flow ............................................................................................... 11-24 1105.4 Design Procedure ..................................................................................................... 11-24 1105.5 Use of Nomographs .................................................................................................. 11-25 1105.6 Design Criteria ......................................................................................................... 11-26 1105.7 Special Considerations ............................................................................................. 11-27

1106 End Treatments ............................................................................................................................. 11-28 1106.1 General .................................................................................................................... 11-28 1106.2 Headwall Types ........................................................................................................ 11-29 1106.3 Concrete Apron ........................................................................................................ 11-30

1107 Rock Channel Protection (RCP) ................................................................................................... 11-30 1107.1 General .................................................................................................................... 11-30 1107.2 Culvert RCP Types ................................................................................................... 11-30 1107.3 Bridge RCP .............................................................................................................. 11-30

1108 Agricultural Drainage..................................................................................................................... 11-31 1108.1 Farm Drain Crossings ............................................................................................... 11-31 1108.2 Farm Drain Outlets ................................................................................................... 11-31

1109 Longitudinal Sewer Location ......................................................................................................... 11-31 1109.1 Under Pavement ...................................................................................................... 11-31 1109.2 Under Paved Shoulder ............................................................................................. 11-32 1109.3 Approval ................................................................................................................... 11-32

1110 Reinforced Concrete Radius Pipe and Box Sections ................................................................... 11-32 1110.1 General .................................................................................................................... 11-32

1111 Sanitary Sewers ............................................................................................................................ 11-32 1111.1 General .................................................................................................................... 11-32 1111.2 Manholes ................................................................................................................. 11-32

1112 Notice of Intent (NOI) .................................................................................................................... 11-32 1112.1 General .................................................................................................................... 11-32 1112.2 Routine Maintenance Project .................................................................................... 11-33

1112.3 Watershed Specific NOI Requirements ..................................................................... 11-34 1113 Erosion Control at Bridge Ends ..................................................................................................... 11-35

1113.1 General .................................................................................................................... 11-35 1113.2 Corner Cone ............................................................................................................. 11-35

1114 Temporary Sediment and Erosion Control ................................................................................... 11-35 1114.1 General .................................................................................................................... 11-35 1114.2 Cost Estimate for Temporary Sediment and Erosion Control ..................................... 11-35

1115 Post Construction Storm Water Structural Best Management Practices ...................................... 11-36 1115.1 General .................................................................................................................... 11-36 1115.2 Project Thresholds for Post-Construction BMP ......................................................... 11-36 1115.3 Water Quality and Water Quantity Treatment ............................................................ 11-37 1115.4 Water Quality Volume ............................................................................................... 11-38 1115.5 Water Quality Flow ................................................................................................... 11-38 1115.6 Project Type - Redevelopment and New Construction .............................................. 11-38

1116 BMP Selection and Submittals ...................................................................................................... 11-40 1116.1 BMP Selection .......................................................................................................... 11-40 1116.2 BMP Submittals ........................................................................................................ 11-41

1117 BMP Toolbox ................................................................................................................................. 11-41 1117.1 Manufactured Systems ............................................................................................. 11-41 1117.2 Vegetation Based BMP............................................................................................. 11-42 1117.3 Extended Detention .................................................................................................. 11-45 1117.4 Retention Basin ........................................................................................................ 11-48 1117.5 Bioretention Cell ....................................................................................................... 11-49 1117.6 Infiltration ................................................................................................................. 11-51 1117.7 Constructed Wetlands .............................................................................................. 11-54

1118 Bridge Hydraulics .......................................................................................................................... 11-55 1118.1 General .................................................................................................................... 11-55 1118.2 Hydrology and Hydraulics (H&H) Report ................................................................... 11-55

APPENDIX A – Reproducible Forms APPENDIX B – Sample Plan Notes APPENDIX C – Drainage Design Aids

Appendix C has been removed from the printed manual. Drainage Aids can be found at the OHE webpage.

Preface

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Purpose

This Drainage Design Manual has been prepared as a guide for the hydraulic design of highway drainage facilities. Drainage is one of the essential components of roadway design. Drainage facilities for most roadway projects account for approximately 25% of the total construction cost of the project. This cost justifies a careful and scientific hydraulic analysis.

Application Design drainage facilities following the recommended design procedures noted in this manual to minimize the following:

Damage of private property due to flooding

Inconvenience to the motorist during moderate to heavy rainfall

Disturbance to the environment Numerous charts have been prepared and are included in the Drainage Design Aids Section of this manual to assist the Drainage Design Engineer with the hydraulic analysis. Other design charts are available in Hydraulic Engineering Circulars and Hydraulic Design Series prepared by the Federal Highway Administration. Reference is made to those charts as required. This manual is neither a textbook nor a substitute for engineering knowledge, experience, or judgment. It is intended to provide uniform procedures for implementing drainage design decisions and assure quality and continuity in drainage of highways in Ohio. Although the manual is considered a primary source of reference by personnel involved in drainage design in Ohio, it must be recognized that the practices suggested may be inappropriate for some projects because of fiscal limitations or other justifiable reasons. Consideration must also be given to justifiable hydraulic design standards adopted by city, county, or other local governments when designing facilities under their jurisdiction.

Preparation The Drainage Design Manual has been developed by the Office of Hydraulic Engineering (OHE). Errors or omissions should be reported to the Administrator, Office of Hydraulic Engineering, Ohio Department of Transportation,1980 W. Broad Street, Columbus, Ohio 43223.

Format and Revisions Updating the manual is intended to be a continuous process. Revisions will be issued periodically by OHE and will be available on the Design Reference Resource Center (DRRC) webpage: http://www.dot.state.oh.us/drrc/Pages/default.aspx. All revisions are shown in red text, and each page has the latest date shown in the bottom corner.

http://www.dot.state.oh.us/drrc/Pages/default.aspx

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Ohio Counties

January 2015 iii

County Code District Adams ADA 9 Allen ALL 1 Ashland ASD 3 Ashtabula ATB 4 Athens ATH 10 Auglaize AUG 7 Belmont BEL 11 Brown BRO 9 Butler BUT 8 Carroll CAR 11 Champaign CHP 7 Clark CLA 7 Clermont CLE 8 Clinton CLI 8 Columbiana COL 11 Coshocton COS 5 Crawford CRA 3 Cuyahoga CUY 12 Darke DAR 7 Defiance DEF 1 Delaware DEL 6 Erie ERI 3 Fairfield FAI 5 Fayette FAY 6 Franklin FRA 6 Fulton FUL 2 Gallia GAL 10 Geauga GEA 12 Greene GRE 8 Guernsey GUE 5 Hamilton HAM 8 Hancock HAN 1 Hardin HAR 1 Harrison HAS 11 Henry HEN 2 Highland HIG 9 Hocking HOC 10 Holmes HOL 11 Huron HUR 3 Jackson JAC 9 Jefferson JEF 11 Knox KNO 5 Lake LAK 12 Lawrence LAW 9

County Code District Licking LIC 5 Logan LOG 7 Lorain LOR 3 Lucas LUC 2 Madison MAD 6 Mahoning MAH 4 Marion MAR 6 Medina MED 3 Meigs MEG 10 Mercer MER 7 Miami MIA 7 Monroe MOE 10 Montgomery MOT 7 Morgan MRG 10 Morrow MRW 6 Muskingum MUS 5 Noble NOB 10 Ottawa OTT 2 Paulding PAU 1 Perry PER 5 Pickaway PIC 6 Pike PIK 9 Portage POR 4 Preble PRE 8 Putnam PUT 1 Richland RIC 3 Ross ROS 9 Sandusky SAN 2 Scioto SCI 9 Seneca SEN 2 Shelby SHE 7 Stark STA 4 Summit SUM 4 Trumbull TRU 4 Tuscarawas TUS 11 Union UNI 6 Van Wert VAN 1 Vinton VIN 10 Warren WAR 8 Washington WAS 10 Wayne WAY 3 Williams WIL 2 Wood WOO 2 Wyandot WYA 1

Concordance

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Anti-seep Collar 11-46 Asbestos 10-11 Backwater Analysis 10-8, 11-22, 11-24 Bankfull

Design 11-6, 11-26, 11-27 Discharge 11-21

Catch Basin Ditches 11-9, 11-10 Pavement 11-13, 11-18

Bypass Flow 11-13 Grates 11-9

Conduits Flexible 11-6, 11-9, 11-16, 11-29, 11-32 Rigid 10-1, 10-10, 10-19, 11-16 Type A 10-2 Type B 10-3, 11-15 Type C 10-4, 11-15 Type D 10-4, 11-28 Type E 10-4, 10-5 Type F 10-4, 11-15, 11-31

Corrugated Metal Pipe Box Culverts 10-13 Flexible 11-16, 11-29 Pipe Arches 10-2

Cover height maximum 10-13, 10-14, 10-15 minimum10-1, 10-12, 10-13, 10-14, 10-15, 11-

16, 11-23, 11-28 Culvert

Bankfull Design 11-6, 11-26, 11-27 Design Frequency 10-7, 11-5 Design Method 11-24 Durability 10-2, 10-3, 10-4 Entrance Loss 11-26 Headwater 11-24, 11-27 Improved inlet 11-28 Inlet Control 11-24, 11-28 Outlet Control 10-3, 11-24

Ditches Design Criteria 11-6, 11-10 Protection 11-6 Shear Stress 11-7 Special 11-5

End Treatment Cutoff Wall 11-22 Full-Height Headwall 11-29 Half-Height Headwall 11-28, 11-29

Energy Dissipator 10-2 Farm Drain 10-4, 11-31 FEMA vi, 10-9 Filter Fabric 10-18, 11-30 Flood

Hazard Evaluation 10-8 Plain vi, 10-7, 10-8, 11-6, 11-23 Plain Coordinator 10-7, 10-10 Plain Culverts 11-23

Foundations v Hydraulic Grade Line vii, 11-18 Hydrology

Rational Equation 11-18 Coefficient of Runoff11-3, 11-17, 11-18, 11-

19 Rainfall Intensity 11-1, 11-4, 11-19 Strip Method 11-12 Time of Concentration11-1, 11-2, 11-12, 11-

19 USGS Regression Equations 10-6

Manhole 10-18, 10-19, 11-19, 11-31 natural stream ix, 10-1, 11-20, 11-24 Pavement Drainage

Design Frequency 11-11 Sag 11-13, 11-14 Spread 11-12

pH viii, 10-3 Plans,Temporary structure 10-20 Precast Concrete Pipe

Arch 10-14, 10-15 Box Culvert 10-13, 10-17, 11-25, 11-28 Rigid 10-1, 11-16 Three-sided Flat Topped10-2, 10-13, 10-14,

10-17, 11-20, 11-28 Rock Channel Protection10-2, 11-7, 11-8, 11-29,

11-48 Sanitary Sewer 11-16, 11-31, 11-32 Soil Bioengineering 11-6 Spread Footings v Storm Sewer

Access 11-17 Design Considerations 11-16 Design Frequency 11-18

Storm Water Pollution Prevention Plan 11-34, 11-35

Subsurface Drainage Aggregate Drains 10-17, 10-19 Construction Underdrains 10-19 Edge Drains 10-17, 10-19 Pipe Underdrains 10-17, 10-18, 10-19

Tailwater 10-9, 11-24, 11-27 Temporary structure, culverts 10-20 Temporary structure, hyraulic storm year 10-20 Temporary structures 10-20 Thermoplastic Pipe 10-12, 11-19, 11-32 USGS x, 10-6, 11-50 Waterproofing 10-17

Glossary of Terms

January 2015 v

Aggregate Drain - A trench filled with granular material extending laterally from the pavement base or subbase layer to an outlet on the roadway foreslope with the intent of draining surface and/or ground water away from the pavement base and/or subbase.

Anti-seep Collar – Device that prevents the flow of water through the surrounding soil around a conduit that is used as an outlet for an infiltration, retention, or detention basin.

Apron - Paving at a pipe inlet or outlet, or upstream of a catch basin, constructed along the channel bottom to prevent scour.

Backwater Analysis - The determination of water surface profiles measured at specific locations upstream from a constriction causing an increased flow depth upstream.

Bankfull Discharge – The flow or stage of a stream corresponding to the highest level of active deposition. It is the discharge that, on the average, fills a main channel to the point of overflowing. For simplicity, it is generally considered to be approximately the 2 year discharge.

Bridge – Structure that has a span greater than or equal to 10 feet as measured in a parallel direction to the roadway centerline.

Camber - A slight convex curve constructed into the bottom of a pipe to overcome anticipated settlement problems.

Cast-in-place Structure - A concrete drainage structure which is placed in forms and cured at its final location. Precast beams on cast-in-place foundations are considered cast-in-place structures.

Catch Basin - A structure for intercepting flow from a gutter or ditch and discharging the water through a conduit.

Coefficient of Runoff (C) - A value, varying with the ground and ground cover, which is used in the Rational formula to determine the amount of a rainfall which is directed to streams and not absorbed into the ground.

Conduit - A closed structure such as a pipe that has a span less than 10 feet as measured in a parallel direction to the roadway centerline.

Corner Bearing Pressure - The pressure generated at the corners of pipe arch structures.

Culvert - A structure which is typically designed hydraulically to take advantage of submergence at the inlet to increase hydraulic capacity. A structure used to convey surface runoff through embankments. A structure, as distinguished from a bridge, which is usually covered with embankment and is composed of structural material around the entire perimeter, although some are supported on spread footings with the stream bed serving as the bottom of the culvert.

Cutoff Wall - A wall that extends downward from the end of a structure to below the expected scour depth, or to a scour-resistant material.

Design Discharge (Q) - The peak rate of flow for which a drainage facility is designed. Usually given in cubic feet per second (cfs).

Design Service Life - The average usable life of a pipe or structure. Certain drainage situations require a 50-year life, more stringent situations require a 75-year design life.

Design Storm - A given rainfall amount, areal distribution, and a time distribution, used to estimate runoff. The rainfall amount is either a given frequency (25-year, 50-year, etc.) or a specific large value.

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Detention Basin – A structure that holds water for a short period of time before releasing it to the natural water course.

Diversion Dike - An embankment to control or to deflect water away from a soil bank.

Drainage Area - The area contributing discharge to a stream at a given point.

Drop-down Entrance (Drop inlet) - A type of inlet which conveys the water from a higher elevation to a lower elevation smoothly without a free fall at the inlet.

Elliptical Pipe - Pipe which is manufactured with a span greater than rise to be utilized in shallow cover situations.

Ephemeral Stream – A stream or reach of stream that does not flow for parts of the year. As used here, the term includes intermittent streams with flow less than perennial. It is located above the water table year-round. Ground water is not a source of water supply.

Feasible – Term used to define BMP practicability. BMP shall be: technically feasible, implemented within the procured highway right-of-way, safe for the traveling public and ODOT maintenance personnel, cost effective as compared to the benefit, and will be legal at the State, Federal, and Local levels. FEMA – Federal Emergency Management Agency.

Flood Fringe – The portion of the floodplain outside of the floodway.

Flood Hazard Evaluation - The act of determining if flood levels within a watercourse for a 100-year flood, or other recurrence interval floods have a significantly increased detrimental impact on upstream property.

Flood Insurance Rate Map (FIRM) - The official map of a community on which FEMA has delineated both the special hazard areas and the risk premium zones applicable to the community.

Flood Insurance Study – A book with information regarding flooding in a community that is developed in conjunction with the FIRM. It discusses the engineering methods used to develop the FIRMs.

Flood Plain – Lowland and relatively flat areas adjoining inland and coastal waters including, at a minimum, that area subject to a one percent or greater chance of flooding in any given year. This area encompasses the floodway and the floodway fringe.

Flood Plain Culverts – Relief culverts that are placed in addition to a bankfull culvert at a higher elevation across the flood plain to allow multiple outlets for floodwaters. Flood Plain Study - A more extensive analysis of the effects of flood levels on upstream property than the Flood Hazard Evaluation. This analysis is to be used when upstream properties appear to have been subjected to a significantly increased detrimental effect from the flood flows.

Floodway – The portion of the floodplain which is effective in carrying flow, within which this carrying capacity must be preserved and where the flood hazard is generally highest.

Flowline – see Thalweg

Forebay – Depressed area that offers pretreatment of sediment laden storm water prior to a retention, detention, or infiltration basin. Friction Slope - The slope of the energy grade line.

Granular Material - A term relating to the uniform size of grains or crystals in rock, larger than sand or pea gravel.

January 2015 vii

Grate - A type of screen made from sets of bars used to allow the interception of flow, and also to cover an area for pedestrian or vehicular traffic.

Headwall - The structural appurtenance placed at the open end of a pipe to control an adjacent highway embankment and protect the pipe end from undercutting.

Headwater - That depth of water impounded upstream of a culvert due to the influence of the culvert constriction, friction, and configuration.

Highest Known Water Elevation – The highest known flood water in record.

Hydraulic Grade Line - A line coinciding with the level of flowing water in an open channel. In a closed conduit operating under pressure, a line representing the distance water would rise in a pitot tube at any point along a pipe. The hydraulic grade line is equal to the pressure head (P/γ) along the pipe.

Hydraulic Gradient - The slope of the hydraulic grade line for a storm sewer or culvert.

Idealized Channel Geometry - Physical, geometric, and hydraulic characteristics of a channel determined from empirical relationships.

Impervious Surface – Hardened pavement surface. Infiltration Rate – The rate at which water penetrates the surface of the soil at any given instant. The rate can be limited by the infiltration capacity of the soil or the rate at which water is applied.

Inlet - A structure for capturing concentrated surface flow. May be located along the roadway, in a gutter, in the highway median, or in the field.

Inlet Control - The situation where the culvert hydraulic performance is controlled by the entrance geometry only.

Intermittent Stream – A stream that is dry for part of the year, ordinarily more than 3 months.

Manhole - A structure by which one may access a closed drainage system.

MS4 Phase II Regulated Area – Area that has been designated by the Ohio EPA that requires a storm water management plan to discharge storm water.

Multiple Cell Culvert - A culvert with more than one barrel.

New Development Project – Projects that change the land use of a site from undeveloped to developed characteristics.

Normal Water Elevation – The water elevation in a stream which has not been affected by a recent heavy rain runoff. The water level which could be found in the stream most of the year. This elevation will be lower than the ordinary high water.

Ordinary High Water – The line on the shore established by the fluctuation of water and indicated by physical characteristics such as: a clear natural line impressed on the bank, shelving, changes in the character of soil, destruction of terrestrial vegetation, or other appropriate means that consider the characteristics of the surrounding areas. This elevation is lower than the highest known water.

Outlet Control - The situation where the culvert hydraulic performance is determined by the controlling water surface elevation at the outlet, the slope, length and roughness of the culvert barrel, as well as the entrance geometry.

Overland Flow - Water which travels over a surface and reaches a stream.

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Perennial Stream – A stream that flows continuously for all or most of the year. The water table is located above the stream bed for most of the year.

Permeability – The quality of the soil that enables water to move downward through the soil profile. It is measured in units of inches per hour.

pH - The reciprocal of the negative logarithm of the Hydrogen ion concentration. Neutral water has a pH value of 7. A measure of the acidity of a substance, if less than 7; alkalinity if greater than 7.

Pipe Arch - Pipe which is manufactured with a span greater than rise (semicircular crown, small-radius corners, and large radius invert) to be utilized in shallow cover situations.

Pipe Underdrain - A longitudinal subsurface drainage system composed of a perforated pipe at the bottom of a narrow trench filled with permeable material and lined with a geotextile in erodible soils, with the intent of draining surface and/or ground waters away from the pavement base and/or subbase.

Porosity – The volume of voids divided by the total volume and multiplied by 100.

Prefabricated Edge Drain - A longitudinal underdrain system utilizing a narrow trench and a vertically elongated, perforated water carrier with the intent of draining surface and/or ground water away from the pavement base and/or subbase.

Prefabricated Structure - Any drainage structure which is manufactured off site and transported to the location of intended use. It may be of various materials, including concrete, clay, metal, thermoplastics, etc. It may be of various shapes including circular, elliptical, rectangular, arched, etc.

Premium Joints - Watertight joints.

Pretreatment – Preliminary filtering of sediment laden storm water prior to secondary treatment through a structural best management practice. Rainfall Intensity (i) - The amount of rainfall occurring in a unit of time, normally given in inches per hour.

Reference Reach - A length of channel with stable geometric, physical, and hydraulic characteristics. A representation of the desired outcome of a restored channel.

Retention Basin – A structure that holds water on a permanent basis. Roughness Coefficient (n) - The measure of texture on the surface of channels and conduits. Usually represented by the “n-value” coefficient used in Manning’s open channel flow equation.

Runoff - That part of the precipitation which runs off the surface of a drainage area after all abstractions are accounted for.

Sanitary Sewer - A conduit or pipe system which carries household and/or industrial wastes. Sanitary sewers do not convey storm water.

Sediment Basin - A basin or tank in which stormwater containing settleable solids is retained, to remove by gravity or filtration a part of the suspended matter.

Sediment Dam - A dam that is designed to allow suspended sediment to settle out of flowing water in a controlled area.

Short-circuiting – The act of storm water bypassing the intended route.

Soil Bioengineering – The use of live and dead plant materials, in combination with natural and synthetic support materials, for slope stabilization, erosion reduction, and vegetative establishment.

January 2015 ix

Spring Line - The locus of the horizontal extremities of a transverse section of a conduit.

Step Backwater or Standard Step Method - An iterative use of the energy equation for determining the water surface profile of an open channel.

Storm Sewer - A conduit or pipe drainage system that conveys storm water, subsurface water, condensate, or similar discharge, but not household or industrial wastes.

Thalweg – The lowest bed elevation in a natural channel cross section. Also used in reference to the profile line extending down a channel along the lowest bed elevation.

Tailwater - The depth of flow in the stream directly downstream of a drainage facility, measured from the invert at the culvert outlet. Often calculated for the discharge flowing in the natural stream without the highway constriction. Term is usually used in culvert design and is the depth measured from the downstream flow line of the culvert to the water surface.

Time of Concentration (tc) - Time required for water to flow from the most distant point on a drainage area to the measurement or collection point.

TMDL (total maximum daily load) Regulated Stream – An Impaired water body as defined by the Ohio EPA that can still meet water quality standards if the daily maximum pollutant load is regulated. Two Stage Channel – A channel that contains a cross sectional area for low and high discharges. Water of The United States - Water bodies subject to Army Corps of Engineers jurisdiction through Section 404 of the Clean Water Act. They include all interstate waters such as lakes, rivers, streams (including intermittent streams) and wetlands. Ephemeral streams are included if they have a clearly defined channel.

Design Reference Documents

x January 2015

Highway Hydrology (FHWA Hydraulic Design Series No. 2) Design Charts for Open Channel Flow (FHWA Hydraulic Design Series No. 3) Hydraulic Design of Highway Culverts (FHWA Hydraulic Design Series No. 5) River Engineering For Highway Encroachments (FHWA Hydraulic Series No. 6) Design of Stable Channels with Flexible Linings (Federal Highway Engineering Circular No. 15) Evaluating Scour at Bridges (FHWA Hydraulic Engineering Circular No. 18) Stream Stability at Highway Structures (FHWA Hydraulic Engineering Circular No. 20) Urban Drainage Design Manual Second Edition (FHWA Hydraulic Engineering Circular No. 22) Bridge Scour and Stream Instability Countermeasures Experience, Selection, and Design Guidance (FHWA Hydraulic Engineering Circular No. 23) Estimation of Peak-Frequency Relations, Flood Hydrographs, and Volume - Duration - Frequency Relations of Ungaged Small Urban Streams in Ohio (USGS Open-File Report 93-135) Estimation of Flood Volumes and Simulation of Flood Hydrographs for Ungaged Small Rural Streams in Ohio (USGS Water Resources Investigations Report 93-4080) Culvert Durability Study (ODOT/L&D/82-1) Internal Energy Dissipators for Culverts (FHWA/OH-84/007) Standard Construction Drawings (ODOT) Construction and Material Specifications Handbook (ODOT) Rainwater and Land Development, Ohio’s Standards for Stormwater Management Land Development and Urban Stream Protection (Third Edition, 2006). Stream Corridor Restoration: Principles, Practices and Processes (United States Department of Agriculture), October 1998 Additional design resources can be found at the FHWA website at:

http://www.fhwa.dot.gov/bridge/hydpub.htm.

Bankfull Characteristics of Ohio Streams and Their Relation to Peak Streamflows (Scientific Investigations Report 2005-5153)

A Streamflow Statistics (StreamStats) Web Application for Ohio (Scientific Investigations Report 2006-5312 FHWA Ultra Urban BMP webpage. (http://www.fhwa.dot.gov/environment/ultraurb/index.htm) USEPA National Pollutant Discharge webpage (http://cfpub.epa.gov/npdes/stormwater/menuofBMP/menu.cfm) Urban Runoff Quality Management, WEF Manual of Practice No. 23, 1998, published jointly by the WEF and ASCE. Ohio Environmental Protection Agencyhttp://www.epa.state.oh.us

http://www.fhwa.dot.gov/bridge/hydpub.htm

http://www.fhwa.dot.gov/environment/ultraurb/index.htm

http://cfpub.epa.gov/npdes/stormwater/menuofbmps/menu.cfm


1000 Drainage Design Criteria 1001 Hydraulic Design Criteria ................................................................................................................ 10-1

1001.1 Responsibilities ............................................................................................................... 10-1 1001.2 Natural Streams .............................................................................................................. 10-1

1002 Pipe Criteria .................................................................................................................................... 10-1 1002.1 Introduction ..................................................................................................................... 10-1

1002.1.1 Deviation by ODOT Districts ........................................................................... 10-1 1002.1.2 Deviation by Local ........................................................................................... 10-1

1002.2 General Requirements .................................................................................................... 10-2 1002.2.1 Pipe Materials ................................................................................................. 10-2 1002.2.2 Outlet Velocity Control .................................................................................... 10-2 1002.2.3 Special Shapes ............................................................................................... 10-2 1002.2.4 Structure File Number/Culvert File Number .................................................... 10-2

1002.3 Conduit Types ................................................................................................................. 10-2 1002.3.1 Type A Conduits ............................................................................................. 10-2 1002.3.2 Type B Conduits ............................................................................................. 10-3 1002.3.3 Type C Conduits ............................................................................................. 10-4 1002.3.4 Type D Conduits ............................................................................................. 10-4 1002.3.5 Type E Conduits ............................................................................................. 10-4 1002.3.6 Type F Conduits .............................................................................................. 10-4 1002.3.7 Culvert Rehabilitation ...................................................................................... 10-5

1003 Hydrology ........................................................................................................................................ 10-6 1003.1 Estimation of Magnitude and Frequency of Floods on Ohio Streams ............................ 10-6

1003.1.1 General ........................................................................................................... 10-6 1003.1.2 Alternate Discharge Sources for Bridges ....................................................... 10-6 1003.1.3 Limitations ....................................................................................................... 10-6

1004 Flood Clearance .............................................................................................................................. 10-7 1004.1 General ........................................................................................................................... 10-7 1004.2 Design Year Frequency .................................................................................................. 10-7

1005 Highway Encroachments on Flood Plains ...................................................................................... 10-7 1005.1 General ........................................................................................................................... 10-7

1005.1.1 Flood Insurance Studies (FIS) ........................................................................ 10-7 1005.1.2 Flood Hazard Mapping .................................................................................... 10-8 1005.1.3 ODOT Self-Permit Process ............................................................................. 10-8

1005.2 Type of Studies ............................................................................................................... 10-9 1005.2.1 Flood Hazard Evaluation................................................................................. 10-9 1005.2.2 Detailed Flood Plain Study .............................................................................. 10-9

1006 Allowable Headwater ...................................................................................................................... 10-9 1006.1 Design Storm .................................................................................................................. 10-9 1006.2 Culvert Headwater Controls ............................................................................................ 10-9

1006.2.1 Design Storm Controls .................................................................................... 10-9 1006.2.2 Check Storm Controls ................................................................................... 10-10 1006.2.3 Limitations ..................................................................................................... 10-10 1006.2.4 Controls Specific to Flood Plain Insurance Studies ...................................... 10-10

1006.3 Bridge Headwater Control ............................................................................................. 10-10 1006.4 Controls Specific to Flood Insurance Studies (FIS) ...................................................... 10-11

1007 Pipe Removal Criteria ................................................................................................................... 10-11 1007.1 General ......................................................................................................................... 10-11 1007.2 Asbestos pipe................................................................................................................ 10-11

1008 Conduit Design Criteria ................................................................................................................. 10-12 1008.1 Corrugated and Spiral Rib Steel and Aluminum Pipes, and Corrugated Steel and Aluminum Pipe Arches .............................................................................................................. 10-12

1008.1.1 Material Durability ......................................................................................... 10-12 1008.1.2 Designation and Thickness ........................................................................... 10-12 1008.1.3 Cambered Flow Line ..................................................................................... 10-12

1008.1.4 Height of Cover ............................................................................................. 10-12 1008.1.5 Foundation Reports ...................................................................................... 10-12

1008.2 Rigid Pipe ...................................................................................................................... 10-12 1008.2.1 General ......................................................................................................... 10-12 1008.2.2 Height of Cover ............................................................................................. 10-13

1008.3 Thermoplastic Pipe ....................................................................................................... 10-13 1008.3.1 Height of Cover ............................................................................................. 10-13

1008.4 Corrugated Steel and Aluminum Box Culverts and Corrugated Steel Long Span Culverts. .................................................................................................................................................. 10-13

1008.4.1 Designation and Thickness ........................................................................... 10-13 1008.4.2 Height of Cover ............................................................................................. 10-13 1008.4.3 Foundation Reports ...................................................................................... 10-13

1008.5 Precast Reinforced Concrete Box Culverts .................................................................. 10-13 1008.5.1 Designation ................................................................................................... 10-13 1008.5.2 Height of Cover ............................................................................................. 10-14 1008.5.3 Structural Design Criteria .............................................................................. 10-14

1008.6 Precast Reinforced Concrete Three-Sided Flat-Topped Culverts ................................ 10-14 1008.6.1 Designation ................................................................................................... 10-14 1008.6.2 Height of Cover ............................................................................................. 10-14 1008.6.3 Structural Design Criteria .............................................................................. 10-14 1008.6.4 Foundation Reports ...................................................................................... 10-14

1008.7 Precast Reinforced Concrete Arch Sections ................................................................ 10-14 1008.7.1 Designation ................................................................................................... 10-14 1008.7.2 Height of Cover ............................................................................................. 10-15 1008.7.3 Structural Design Criteria .............................................................................. 10-15 1008.7.4 Foundation Reports ...................................................................................... 10-15

1008.8 Precast Reinforced Concrete Round Sections ............................................................. 10-15 1008.8.1 Designation ................................................................................................... 10-15 1008.8.2 Height of Cover ............................................................................................. 10-16 1008.8.3 Structural Design Criteria .............................................................................. 10-16 1008.8.4 Foundation Reports ...................................................................................... 10-16

1008.9 Arch or Flat Slab Top Culvert Foundations ................................................................... 10-16 1008.10 Bridge Foundations ..................................................................................................... 10-17 1008.11 Waterproofing Membrane ........................................................................................... 10-17 1008.12 Precast Reinforced Concrete Flat Slab Tops, Catch Basin Tops, and Inlet Tops ...... 10-18 1008.13 Wingwall Design.......................................................................................................... 10-18

1009 Subsurface Pavement Drainage ................................................................................................... 10-18 1009.1 General ......................................................................................................................... 10-18 1009.2 Types of Subsurface Drainage ..................................................................................... 10-18

1009.2.1 Pipe Underdrains .......................................................................................... 10-18 1009.2.2 Construction Underdrains ............................................................................. 10-19 1009.2.3 Prefabricated Edge Drains ............................................................................ 10-19 1009.2.4 Aggregate Drains .......................................................................................... 10-19

1010 Maintenance of Traffic Drainage ................................................................................................... 10-20 1010.1 General ......................................................................................................................... 10-20

1011 Temporary Structures ................................................................................................................... 10-20

1000 Drainage Design Criteria

January 2015 10-1

1001 Hydraulic Design Criteria

1001.1 Responsibilities

The Office of Hydraulic Engineering (OHE) is responsible for the hydraulic design standards for all surface drainage systems and bridge structures owned and maintained by the Department. Further responsibility includes: conduit durability, culvert inspection and inventory, post construction storm water best management practices, and the Department’s Municipal Separate Storm Sewer System (MS4) program.

1001.2 Natural Streams

Channel designs and channel relocations of all natural streams passing through a proposed highway facility will be the responsibility of the owner. All other channel designs and channel relocations of natural streams are the responsibility of OHE.

1002 Pipe Criteria

1002.1 Introduction

The Departments Pipe Criteria governs the determination of the size and type of pipe specified or permitted for the various items of highway drainage financed totally or in part with state or federal funds. Deviations from this Pipe Criteria concerning type of pipe or pipe placement must be based on sound engineering judgment and/or life cycle cost analysis. Deviations involving the specification of only one type of pipe material where special conditions prevail must include sound engineering judgment such as:

Excessive cover for a rigid pipe.

Where a larger corrugated pipe would require a higher pavement grade to satisfy minimum cover requirements or require more cells than a rigid alternate.

Where a metal pipe arch would be required as an alternate to a round rigid pipe.

The outfall velocity would require an energy dissipater.

Site conditions prevented the existing conduit material to meet design service life. Verification that the existing conduit material had been correctly designed to ODOT durability design needs to be documented.

The use of a single material type is subject to the approval of OHE. 1002.1.1 Deviation by ODOT Districts

ODOT Districts may submit a written request for deviation from this Pipe Criteria. Include documentation that justifies the deviation and the completed Drainage Criteria form (see Appendix A). Submit the documentation to the Administrator of OHE. 1002.1.2 Deviation by Local

Proposed deviations from this Pipe Standard and/or construction specifications by local political subdivisions or agencies will be considered for all portions of the project that are maintained by the political subdivision or agency. ODOT Districts may permit a deviation from this Pipe Standard provided the local political subdivision or agency agrees to fund any additional costs inferred due to the conduit material selection or preferred construction methods. The deviation requires alternate bid items, per Section 1307.2.7 of L&D Volume 3, to determine the additional costs. The alternatives include ODOT’s Pipe Standard/construction methods and the local’s material selection/construction methods. Add additional notes or details as required by the local.

Drainage Design Criteria

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1002.2 General Requirements

1002.2.1 Pipe Materials

The type of pipe materials listed under the various conduit types in Section 611.02 of the Construction and Material Specifications are considered equal within their size, structural and material durability limitations. 1002.2.2 Outlet Velocity Control

When permissible pipe alternates have different velocity characteristics, the design specified for erosion control will satisfy the most severe velocity condition of the permissible alternates. In this case, “erosion control” refers to controls placed in the stream channel at the outlet end of the pipe such as rock channel protection, and does not refer to energy dissipaters. Where the calculated culvert outlet velocity exceeds 20 feet per second or 15 feet per second in areas of poor soil such as fine sand or sandy silt, roughness elements (protruding concrete rings inside the pipe) may be specified at the outlet end of the alternates to reduce the velocity below the maximum allowable. The design of internal energy dissipator ring chambers is provided in report FHWA/OH-84/007 “Internal Energy Dissipators for Culverts”. This report and ring chamber details can be obtained from OHE. Where the outlet velocity for a corrugated pipe is less than 20 feet per second while the outlet velocity for a smooth pipe requires a ring chamber, the corrugated pipe may be specified exclusively. 1002.2.3 Special Shapes

Special shaped conduits (elliptical concrete, corrugated metal arch or pipe arch, or prefabricated box or three-sided structures) are generally limited for use under shallow cover installations or extremely low or restrictive headwater control otherwise requiring multiple circular conduits to satisfy allowable headwater conditions. Generally elliptical concrete and corrugated metal pipe arch of the required size to satisfy hydraulic conditions are to be shown on the plan. Special shaped conduits may be provided to conform to the cross-sectional geometry of sensitive streams identified in the environmental documentation. Where corrugated metal and structural plate pipe arches are specified or permitted, a foundation investigation shall be submitted as required by Section 1008.1.5. 1002.2.4 Structure File Number/Culvert File Number

Structures having an opening measured along the centerline of roadways of 10’ or greater require a Structure File Number (SFN). Multiple openings where the extreme ends of the openings are 10’ or greater also require a SFN, where the clear distance between opening is less than half of the smaller contiguous opening. Structures having an opening measured along the centerline of roadway of less than 10’ require a Culvert File Number (CFN). The CFN is provided by the District Office in accordance to the Culvert Management Manual.

1002.3 Conduit Types

1002.3.1 Type A Conduits

Type A conduits shall be designated for soil-tight, sealed-joint, open-ended cross drains under pavements and paved shoulders. The minimum size culvert (or cross drain) to be specified shall be based on the roadway type and depth of fill from the flowline to roadway surface.


January 2015 10-3

The minimum required round (or equivalent deformed) pipe sizes are listed in Figure 1002-1. For culverts under freeways or high fills (16 feet), the size shall be increased one pipe size over the required size to allow for future repair. Ensure the pipe is only upsized once. All hydraulically adequate pipe alternates which provide the required service life shall be shown on the plans and listed in the pertinent pay item. In the applicable size ranges, alternates should include, vitrified clay, concrete, plastic, corrugated steel, and corrugated aluminum. For corrugated metal pipe, the corrugation profile which requires the thinnest metal shall be listed. Where durability requires increased thicknesses of the corrugated steel alternate, the 1-inch corrugation profile should be specified for pipe diameters over 48 inches. For the steel corrugation profile specified, all combinations of thickness and protection providing the required service life shall be specified. If the alternates listed in the plan are different sizes, show the pipe length associated with the smallest pipe size. When extending existing Type A conduits, ensure the extensions match the existing material in kind. Furnish all Type A conduits under State and Federal routes with a minimum service life of 50 years. Use a service life of 75 years at sites that have one of the following characteristics: 1. Fill Height >= 16 feet (measured from flowline to finished grade)

2. Freeways The pH of the normal stream flow and the presence of abrasive flow conditions are factors that determine the material durability and service life. Measure the pH of the normal stream flow in the field using a calibrated pH meter capable of measuring to a tenth. Determine if the streambed material is abrasive by observation. Presence of sand, pea gravel, or sharp cobbles where a stream gradient or flow is sufficient to cause movement of the material would be an indicator that the site is abrasive. Otherwise, the site should be considered non-abrasive. Field measurement of pH is required. Use Figures 1002-2 and 1002-3 if flow is not present in the conduit. Use Figures 1002-4, 5 and 6 to determine the pipe materials for the design service life. These tabulations are based on the ODOT Culvert Durability Study and later reports. Ensure the pH and abrasiveness determination is included in the plans in accordance to L&D, Volume 3. If it is known that future flow conditions will be more corrosive than existing conditions, specify protection that is greater than what is currently required. Submit documentation of the known future flow condition and the proposed additional protection.. 1002.3.2 Type B Conduits

Type B conduits shall be designated for soil-tight, sealed joint sewers under pavements, paved shoulders, and commercial or industrial drives. In areas with highly erodible soils (e.g., fine sands or silts), premium joints shall be provided. Additional protection (epoxy coating as per 706.03 for concrete pipe and polymer coating per 707.04 for asphalt paved corrugated steel pipe) shall be provided for storm sewers carrying corrosive flow. Conduit placed through MSE walls or in the fill of MSE walls are limited to 706.02 with joints per 706.11. The design service life for all Type B conduit is 75 years. No additional design considerations are required to achieve the design service life.


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1002.3.3 Type C Conduits

Type C conduits shall be designated for soil-tight, sealed joint sewers not under pavements, paved shoulders, or commercial or industrial drives. In areas with highly erodible soils (e.g., fine sands or silts), premium joints shall be provided. Additional protection (epoxy coating as per 706.03 for concrete pipe and polymer coating per 707.04 for asphalt paved corrugated steel pipe) shall be provided for storm sewers carrying corrosive flow. The design service life for all Type C conduit is 75 years. No additional design considerations are required to achieve the design service life. 1002.3.4 Type D Conduits

Type D conduits shall be designated for pipes under driveways and bikeways. The minimum size required is 12 inches. For sizes 24 inches and larger, it will be necessary to submit calculations and specify pipe sizing required to satisfy the hydraulic controls. Such analyses shall be submitted with the Drainage Review plans. The design frequency used to analyze the hydraulic performance of the Type D conduit is the same as that used for the flow capacity of the connected ditch or channel and the headwater for that frequency shall not exceed a point 1 foot below the edge of the pavement. If potential exists for the drive pipe headwater to encroach on the adjacent roadway, the drive pipe shall be sized utilizing a design frequency as per 1004.2. Generally, the pipe alternates listed in 611.02 of the Construction and Material Specifications are applicable, except that equal size corrugated pipe will provide satisfactory alternates for sizes smaller than 24 inches. If the control is critical, a hydraulic analysis will be required to determine the proper size of pipe alternates. Drive pipes under commercial or industrial drives shall be designed for material durability as per 1002.3.1. Additional protection for residential and field drives may be specified if conditions warrant. 1002.3.5 Type E Conduits

Type E conduits shall be designated for farm drain headers inside or outside of the right-of-way lines. Headers are ordinarily provided to intercept small, closely spaced lines in a tiled field thereby precluding the need for numerous field tile outlets through the backslope of the highway ditch. 1002.3.6 Type F Conduits

Type F conduits shall be designated where a butt joint or a short length jointed pipe would be undesirable as noted below: A. For the steep portion of a median outlet under an embankment slope 4:1 or steeper, including any

necessary pipe bends. B. For the outlets of underdrains or farm drains through the slope or connecting to a drainage structure.

When used for underdrain outlets, the following pay item description shall be used: Item 611 " Conduit, Type F for Underdrain Outlets. Provide 10 feet of conduit at each outlet into a drainage structure.

C. For farm drains larger than 12 inches that outlet through slopes flatter than 4:1, provide a 20 foot

length of Type F Conduit with an animal guard at the outlet. D. For pipe underdrains that span the trench of a lower conduit, unless the crossing is more than 12

inches above the granular backfill of the lower conduit, provide a minimum length of 10 feet of Type F Conduit.


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Type F conduits may be used beyond the paved shoulder to eliminate a ditch in front of a yard where such ditch elimination can be justified. When required by hydraulic analysis, all proper sized alternates shall be specified. 1002.3.7 Culvert Rehabilitation

A range of material applications and solutions are available for culvert rehabilitation. These solutions are used to extend the service life of existing conduits by adding durability or in some cases structural strength. The following specifications or methods are available: A. CMS 611.11 – Field Paving of Existing Pipe

B. Supplemental Specification 833 – Conduit Renewal Using Spray Applied Structural Liner

C. Supplemental Specification 834 – Conduit Renewal Using Resin Based Liner

D. Supplemental Specification 837 – Liner Pipe (various material)

E. Supplemental Specification 841 – Conduit Renewal Using Spiral Wound Liner

F. Supplemental Specification 937 – Polyethylene Liner Pipe

G. Supplemental Specification 938 – Steel Reinforced Thermoplastic Ribbed Pipe Field paving of existing conduits has been a solution to add durability to conduits for many years. This solution is a cost effective way to add many years of service life to an existing conduit provided the culvert has good structural shape and is structurally sound (ie: not moving). This solution should always be evaluated first. Supplemental Specification 833 – Conduit Renewal Using Spray Applied Structural Liner is a solution that provides structural rehabilitation to existing conduits via a spray application. The interior of the conduit is spray lined with a factory blended cementitious, geopolymer or resin based material. Supplemental Specification 834 – Conduit Renewal Using Resin Based Liner is a solution that adds durability by placing a resin based material on the interior of the existing conduit via a spray application. This solution will add service life to an existing conduit. Supplemental Specification 837- Liner Pipe offers a solution that lines an existing conduit with another conduit. This specification requires the slip-lined conduit to be grouted in-place and in some cases would be considered a structural solution if the slip-lining material is designed accordingly. Supplemental Specifications 937 & 938 are additional material options utilized by Supplemental Specification 837. Ensure all available Liner Pipe materials in Supplemental Specification 837 are shown in the plans if they satisfy the hydraulic conditions. Ensure the hydraulic calculations are evaluated for the alternative slip-line materials. Submit all Liner Pipe projects to OHE for review and approval if one material alternative is specified in the plans. Furnish a cost analysis verifying the use of a single material option. Supplemental Specification 841 – Conduit Renewal Using Spiral Wound Liner is a unique solution that may be used to line various shaped conduits such as: Round, Elliptical, Box, or Pipe Arch. This solution custom manufactures the conduit on site from polyvinyl chloride material with either a special machine or by manual labor. The manufactured conduit is placed into the existing conduit and the void is filled with grout. This solution adds durability to the existing host conduit. Use of this solution requires approval from OHE. The culvert rehabilitation method shall be designed to match existing headwater conditions. Appropriate erosion control measures shall be designed for increased outlet velocities. If the proposed design does not meet the existing headwater conditions or the outside diameter constraint described above, contact OHE for approval.


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Additional information and guidance for culvert rehabilitation can be found at: http://www.dot.state.oh.us/Divisions/Engineering/Hydraulics/Pages/default.aspx

1003 Hydrology

1003.1 Estimation of Magnitude and Frequency of Floods on Ohio Streams

1003.1.1 General

USGS Water Resources Investigations Report 89-4126 “Techniques for Estimating Flood-Peak Discharges of Rural Unregulated Stream in Ohio” was developed cooperatively by the United States Geological Survey and the State of Ohio. This bulletin is an update of Bulletin 32 (1959), Bulletin 43 (1969), and Bulletin 45 (1977). This report provides the latest hydrologic information for determining the magnitude and frequency of floods for rural streams in Ohio. USGS Report 06-5312 “StreamStats” is a USGS web based application for estimating stream flow statistics and basin characteristics on unregulated streams. Use StreamStats or the techniques presented in Report 03-4164 to determine the design peak discharge for hydraulic structures designated by or for ODOT. When applying this technique, the tributary with the largest contributing drainage area, not the longest reach, should be considered. USGS Water Resources Investigation Report 93-4080 “Estimation of Flood Volumes and Simulation of Flood Hydrographs for Ungaged Small Rural Streams in Ohio” shall be used to determine flood volumes and hydrographs for rural areas within the limits prescribed in the report. 1003.1.2 Alternate Discharge Sources for Bridges

Discharge estimates may be calculated by other methods for comparisons against verified flood eleva-tions and other known river data to ensure that the most realistic discharge for the area is used for the design of the waterway opening. Submit calculations and comparisons to the Office of Hydraulic Engineering for review. Flood Insurance Studies (FIS); U.S. Corps of Engineer Flood Studies; U.S. Soils Conservation Studies; U.S. Water Resources Data and other reliable sources may be used as reference information in esti-mating discharges and flood elevations. However, for waterway crossings located in a FIS area, the base discharge (Q100) from the FIS takes precedence over all other calculated discharges. Where a U.S. Geological Survey estimate is in conflict with that of another agency, contact the agency in order to resolve the discrepancy. In general, the U.S. Geological Survey estimate is given preference. Design proposed structures upstream or downstream from a flood control facility for discharges as supplied by the U.S. Corps of Engineers, Ohio Department of Natural Resources or the agency respon-sible for the flood control facility. 1003.1.3 Limitations

Specific limitations on the use of the USGS reqression equations can be found in each report. The USGS Report 89-4126 and USGS 2006-5312 were developed for flood-peak discharge estimates for unregulated streams draining rural basins. USGS Open File Report 2432 "Estimation of Peak-Frequency Relations, Flood Hydrographs, and Volume - Duration - Frequency Relations of Ungaged Small Urban Streams in Ohio” may be used in the design of culverts, detention basins, large storm sewers, and large open channels with urban drainage areas within the limits prescribed in the report. Use the rational method (Section 1101.2.2) in the design of pavement inlets, roadway ditches, culverts, and small storm sewers. Use this method for drainage areas up to a maximum of 200 acres where no well defined natural channel exists and sheet flow prevails.

http://www.dot.state.oh.us/Divisions/Engineering/Hydraulics/Pages/default.aspx


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For additional guidance on the proper use of USGS regression equations see Transportation Research Record 1319 Report “Information Needs for the Proper Application of Hydrologic Regional Regression Equations”.

1004 Flood Clearance

1004.1 General

Where a new highway crosses or is located in a flood plain, the highway grade shall normally be set such that the low edge of the pavement will clear the design water surface profile for existing conditions by 3 feet, and bridges (low chord) will generally clear the water surface profile of the design year frequency flood. These clearances may be reduced where an economic comparison of alternatives shows that a reduction in clearance will result in significant savings, giving full consideration to future flood-related costs relative to: highway operation, maintenance, and repair; highway-aggravated flood damage to other property; and for additional or interrupted highway travel. Flood clearances may also be reduced to protect important ecological resources as identified in the environmental documentation. An economic comparison of alternatives shall be performed to determine the future flood-related costs relative to: highway operation, maintenance, and repair; highway-aggravated flood damage to other property; and for additional or interrupted highway travel.

1004.2 Design Year Frequency

Freeways or other multi-lane facilities with limited access.…..….. 50 Year Other Highways (2000 ADT and over) and Freeway Ramps…….. 25 Year Other Highways (under 2000 ADT)………………………….…....... 10 Year *Bicycle pathway………………………………………………..……… 5 Year * Unless otherwise approved by OHE.

1005 Highway Encroachments on Flood Plains

1005.1 General

The requirements of the Code of Federal Regulations, Volume 23, Part 650A, shall be followed for all projects. All highways that encroach on flood plains, bodies of water or streams, shall be designed to permit conveyance of the 100-year flood without causing significant damage to the highway, the stream, body of water or other property. Hydraulically design structures and/or channels to convey the design-year discharge. Ensure the structure and/or channel will convey the 100-year discharge without causing property damage. Inundation of the highway is acceptable for the 100-year discharge, but it is not permitted for the design-year discharge. Water surface elevations caused by existing structures do not have to be lowered to meet the 100-year discharge. Longitudinal highway encroachments require alternative location studies to be summarized in the Conceptual Alternatives Study (L&D Section 1403.3). 1005.1.1 Flood Insurance Studies (FIS)

Special consideration must be given when designing a structure located within a reach of channel that is part of a FIS. Perform a step backwater analysis of the flood plain to the extent required due to the proposed work. The proposed maximum allowable 100-year water surface elevation is limited to the existing 100-year water surface elevation presented in the FIS. Inform the Local Floodplain Coordinator of any proposed construction within the limits of a flood prone area as designated by an FIS (see 1006.4). Compliance to federal, state and local floodplain standards is required; however, obtaining a permit from


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the Local Floodplain Coordinator is not required for work administered by or for the Department. The Department will self-permit under this process. In order to maintain and verify compliance, thorough documentation is necessary. A Letter of Compliance and depending on the Zone a No-Rise Certification will need to be submitted to the Local Flood Plain Coordinator. Locally administered projects are required to obtain a permit from the Floodplain Coordinator. http://soilandwater.ohiodnr.gov/portals/soilwater/pdf/floodplain/Floodplain%20Manager%20Community%20Contact%20List_10_14.pdf 1005.1.2 Flood Hazard Mapping

Flood hazard areas identified on the Flood Insurance Rate Map (FIRM) are identified as a Special Flood Hazard Area (SFHA). SFHA are defined as the area that will be inundated by the flood event having a 1-percent chance of being equaled or exceeded in any given year. The 1-percent annual chance flood is also referred to as the 100-year event. Floodways are created by a computer model that places encroachments within the floodplain until a 1 foot surcharge is established using the 100 year event discharge (see Figure 1006.1). The water elevation determined from the computer model for the floodway is referred to as the base flood elevation (BFE). Local authorities may reduce the allowable surcharge below the 1 foot criteria, which is why early coordination with the Local Floodplain Coordinator is required. The Ohio Department of Natural Resources (ODNR) administers the Floodplain Management Program for Ohio. ODNR has authority over Local Floodplain Coordinators in accordance to Ohio Revised Code. Additional information can be found at: http://soilandwater.ohiodnr.gov/water-use-planning/floodplain-management SFHAs are labeled as different Zones. Flood Insurance Zone designations may be accessed at the following web site: https://msc.fema.gov/webapp/wcs/stores/servlet/info?storeId=10001&catalogId=10001&langId=-1&content=floodZones&title=FEMA%2520Flood%2520Zone%2520Designations The more common FIS Risk zones are as follows:

ZONE DESCRIPTION

A Areas subject to inundation by the 1-percent-annual-chance flood event. Because detailed hydraulic analyses have not been performed, no BFE or flood depth is shown.

AE, A1-A30 Areas subject to inundation by the 1-percent-annual-chance flood event determined by detailed methods. BFEs are shown within these zones. (Zone AE is used on new and revised maps in place of Zones A1-A30).

Construction within Zone A requires documentation through the ODOT self-permit process and

coordination with the Local Floodplain Coordinator. A BFE has not been established. Limit the water

surface surcharge to the requirements from the Local Floodplain Coordinator or one (1) foot, whichever is

less. Contact OHE if the allowable surcharge required by the Local Floodplain Coordinator is not

feasible.

DConstruction within Zone AE or A1-A30 requires documentation through the ODOT self-permit process,

coordination with FEMA, ODNR, and the Local Floodplain Coordinator. The allowable rise above the

BFE surcharge is limited to zero (0.00 feet). If the BFE is exceeded than a variance is required.

1005.1.3 ODOT Self-Permit Process

Furnish a letter of compliance and hydraulic calculations to the Local Floodplain Coordinator in Zone A areas. Ensure the documentation is kept in the project file.

http://soilandwater.ohiodnr.gov/portals/soilwater/pdf/floodplain/Floodplain%20Manager%20Community%20Contact%20List_10_14.pdf

http://soilandwater.ohiodnr.gov/portals/soilwater/pdf/floodplain/Floodplain%20Manager%20Community%20Contact%20List_10_14.pdf

http://soilandwater.ohiodnr.gov/water-use-planning/floodplain-management

http://soilandwater.ohiodnr.gov/water-use-planning/floodplain-management

https://msc.fema.gov/webapp/wcs/stores/servlet/info?storeId=10001&catalogId=10001&langId=-1&content=floodZones&title=FEMA%2520Flood%2520Zone%2520Designations

https://msc.fema.gov/webapp/wcs/stores/servlet/info?storeId=10001&catalogId=10001&langId=-1&content=floodZones&title=FEMA%2520Flood%2520Zone%2520Designations


January 2015 10-9

Furnish a letter of compliance, no-rise certification and hydraulic calculations to the Local Floodplain Coordinator if the rise above the BFE is zero (0.00 feet). Ensure the documentation is kept in the project file. See Appendix A for LD-50; No-Rise Certification and LD-51; Floodplain Letter of Compliance Template.

Furnish a non-compliance letter requesting a variance along with hydraulic calculations to the Local Floodplain Coordinator and ODNR if the rise above the BFE is not zero (0.00). Further coordination between the Local Floodplain Coordinator, ODNR and FEMA is required. Ensure the documentation is kept in the project file.

1005.2 Type of Studies

1005.2.1 Flood Hazard Evaluation

A flood hazard evaluation is required for all water course involvements except for crossings where roadway culverts are provided to satisfy minimum size requirements. . A Flood Hazard Evaluation is a condition statement regarding the nature of the upstream area, the extent of upstream flooding, and whether buildings are in the 100 year frequency flood plain. Perform the following for a flood hazard evaluation: A. Determine the water surface elevation of the design year and 100-year flood.

B. Delineate the water surface elevation for the design year and 100-year flood on a topographic map or

a digital map.

C. Evaluate the significance of any increase in the flooding limits. 1005.2.2 Detailed Flood Plain Study

If the Flood Hazard Evaluation indicates a significant increase in the flooding of upstream property, a Detailed Flood Plain Study is required. Furnish a Detailed Flood Plain Study in highly urbanized areas where the potential for flooding cannot be accurately assessed without an analysis of the entire flood plain. For prefabricated structures, the Detailed Flood Plain Study, including a step-backwater analysis, will be authorized after review of the Flood Hazard Evaluation, by OHE.

1006 Allowable Headwater

1006.1 Design Storm

The frequency of the design storm shall be as stated in Section 1004.2.

1006.2 Culvert Headwater Controls

1006.2.1 Design Storm Controls

Headwater depth for all culverts (Type A Conduits) shall not exceed any of the following controls for the design storm: A. 2 feet below the near, low edge of the pavement for drainage areas 1000 acres or greater and 1 foot

below for culverts draining less than 1000 acres. B. 2 feet above the inlet crown of the culvert or above a tailwater elevation that submerges the inlet

crown in flat to rolling terrain.


10-10 January 2015

C. 4 feet above the inlet crown of a culvert in a deep ravine. D. 1 foot below the near edge of pavement for bicycle pathways. 1006.2.2 Check Storm Controls

Headwater depth for all culverts (Type A Conduits) shall not exceed any of the following controls for the applicable check frequency storm. A. 2 feet below the lowest ground elevation adjacent to an occupied building for a 50-year storm (it is not

intended, however, to lower existing high water elevations around buildings). B. The designer should generally limit the maximum 100-year headwater depth to twice the diameter or

rise of the culvert. C. A replacement structure should be sized to prevent overtopping by the 100-year flood where such

overtopping would not occur with the existing structure. D. A replacement structure should be sized such that flooding of upstream productive land is not

increased for the 100-year flood when compared to the existing structure. Judgment shall be used in implementing this criteria, considering the type of upstream property and sensitivity to the accuracy of the computed flood stages.

E. No increase in 100-year headwater elevation shall occur in a FEMA designated floodway. 1006.2.3 Limitations

1006.2.1 B and C; and 1006.2.2 B, are arbitrary headwater controls. When 1006.2.1 B is applicable, use smooth pipe to establish the allowable headwater in feet. When 1006.2.1 C controls, use corrugated pipe to establish the headwater and thereby permit the same headwater elevation regardless of type of pipe. More heading will be considered if pipe sizes can be reduced and not cause flooding damage upstream or excessive outlet velocity. 1006.2.1 B and C are arbitrary controls and generally apply to small culverts. Where large structures (greater than or equal to 10 feet in span) are involved, the structure should be sized to pass the design storm while maintaining a free water surface through the structure, unless tail water controls. The near low edge of pavement is the location where roadway overtopping will occur. This may or may not be located directly over the culvert. Where the overtopping point on the roadway is outside the watershed break, the ditch break overflow elevation should be utilized as a headwater control in lieu of 1006.2.1 A. 1006.2.4 Controls Specific to Flood Plain Insurance Studies

When making an encroachment on a NFIP designated floodplain in the floodway fringe, the rise in the water surface above the natural 100 year flood elevation is limited by the community. Contact the community to determine the allowable rise. No increase in the 100 year water surface is allowed when encroaching on a NFIP designated floodway.

1006.3 Bridge Headwater Control

Evaluate the headwater generated by a bridge in accordance to a flood hazard evaluation. Ensure the headwater meets the following: A. Match the existing headwater for a bridge replacement for the design storm and the check flood to the

maximum extent practicable. Any increase in headwaters verify the upstream impacts


January 2015 10-11

B. Design flood does not contact the low chord for new structures on new alignment.

C. Regulations from Conservancy Districts if they are more restrictive than the Departments

D. Controls specific to a FIS.

1006.4 Controls Specific to Flood Insurance Studies (FIS)

Contact the local floodplain coordinator early in the design process to determine the allowable headwater

increase and or the permitting requirements. A current list of floodplain coordinators may be found at:

http://www.dnr.state.oh.us/Portals/7/floodpln/communitylist.pdf.

When making an encroachment on a FIS designated floodplain in the floodway fringe, the rise in the water surface above the natural 100 year flood elevation is limited by the community. See Figure 1006-1 for a graphical definition of the floodway, floodway fringe, and flood plain. No increase in the 100 year water surface is allowed when encroaching on a FIS designated floodway.

1007 Pipe Removal Criteria

1007.1 General

Use the following guidelines to determine whether an existing pipe, regardless of type, being taken out of service should be abandoned or removed. A. Pipes 8 inches in diameter or rise, or less, regardless of depth or height of fill, may be abandoned in

place. B. Pipes 10 inches through 24 inches in diameter or rise with less than 3 feet of final cover should be

removed or filled; with more than 3 feet of final cover they may be abandoned in place. (The designer should use discretion in removing small pipes under existing rigid pavement or base, which is to remain in place.)

C. Pipes over 24 inches in diameter or rise should generally be removed. (The designer should use

discretion in removing any pipe with more than 10 feet of cover.)

1007.2 Asbestos pipe

Asbestos pipe is a regulated material. Designers should make reasonable efforts to identify existing asbestos pipes in the plans and, when necessary, provide appropriate removal quantities. In the past, pipe containing asbestos was allowed on ODOT, LPA and utility projects under the following specifications:

ASTM C663 Asbestos-Cement Storm Drain Pipe

AASHTO M217

AWWA C400

AWWA C603

ASTM C296 Asbestos-Cement Pressure Pipe

ODOT CMS 707.09 Asbestos Bonded Bituminous Corrugated Steel Pipe and Pipe Arches (Circa 1983)

ODOT CMS 706.15 Asbestos Cement Perforated Underdrain Pipe (Circa. 1973) Transite is a common brand name for a type of asbestos pipe. Asbestos can also be found in insulation wrapped around water pipes.

Reasonable efforts to identify asbestos pipes would include the following:

http://www.dnr.state.oh.us/Portals/7/floodpln/communitylist.pdf


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A. Examination of original construction plans and specifications. B. Contact with the owner of the pipe (e.g., utility company or LPA). C. Inspection of the pipe for markings when the pipe is exposed during routine maintenance operations. Removal of asbestos pipe is specified in the most current CMS as Item 202 Asbestos Pipe Removed. For projects to be constructed under the 1997 CMS, use Item 202 Pipe Removed, As Per Plan and indicate that the pipe must be removed by a certified asbestos contractor. Asbestos is a hazard only when it becomes airborne. Pipes that are otherwise unaffected by ODOT work do not need to be removed simply because they contain asbestos. Not all asbestos pipes will be identified by a records search. Construction inspectors are being advised to test suspicious pipe for asbestos. If asbestos pipe is identified, the contractor will be compensated by change order.

1008 Conduit Design Criteria

1008.1 Corrugated and Spiral Rib Steel and Aluminum Pipes, and Corrugated Steel and Aluminum Pipe Arches

1008.1.1 Material Durability

The Criteria outlined in Section 1002 specifying types of protective coatings and/or extra metal thickness shall be followed. 1008.1.2 Designation and Thickness

The corrugation profile and required metal thickness for structural strength is furnished by the Manufacturer in accordance to Construction and Material Specifications Handbook (CMS) Item 611. 1008.1.3 Cambered Flow Line

Where soil conditions at the site indicate that appreciable settlement is expected, provide a cambered flow line. Show the cambered flow line as a vertical curve following the Manufacturer recommendation. 1008.1.4 Height of Cover

See General Notes for Figures 1008-1 through 1008-6 and 1008-15 through 1008-19 for minimum height of cover. 1008.1.5 Foundation Reports

Conduct an investigation of the supporting foundation material to estimate the bearing capacity of the material and determine that no settlement will occur. A foundation investigation is required for all proposed metal pipe installations with 100 feet of fill or more and all pipe arch installations. Submit the foundation report with the Stage 1 review. Refer to section 1008.9 for information on foundation types.

1008.2 Rigid Pipe

1008.2.1 General

Where soil conditions at the site indicate that appreciable settlement is expected, provide a cambered flow line. Show the cambered flow line as a vertical curve following the Manufacturer recommendation.


January 2015 10-13

1008.2.2 Height of Cover

The maximum allowable height of cover is measured from the top of the pipe to the pavement surface. The minimum cover, from the top of the pipe to the top of the subgrade, or finish grade for pipe not under pavements, is 9 inches; however, in no installation shall the distance from the top of the pipe to the pavement surface be less than 15 inches.

1008.3 Thermoplastic Pipe


The maximum allowable height of cover is measured from the top of the conduit to the pavement surface or to finished grade for pipes not under pavement. The minimum cover, from the top of the pipe to the top of the subgrade, is 12 inches; however, in no installation shall the distance from the top of the pipe to the pavement surface, or finish grade for pipes not under pavement, be less than 18 inches.

1008.4 Corrugated Steel and Aluminum Box Culverts and Corrugated Steel Long Span Culverts.

1008.4.1 Designation and Thickness

The corrugation profile and metal thickness required shall be in accordance with the AASHTO LRFD Bridge Design Specifications design methodologies. Structural strength design is furnished by the Manufacturer in accordance to Construction and Material Specifications Handbook (CMS) Item 611. The skew of the structure relative to the roadway shall be given in 1° increments and typically should not exceed 15°. 1008.4.2 Height of Cover

In no case shall the minimum cover, measured from the trough of the corrugation profile to the pavement surface, be less than 18 inches. In addition to the above requirements, corrugated steel and aluminum box culverts shall be provided with adequate cover to ensure that the culvert rib stiffeners are located completely within the subgrade. 1008.4.3 Foundation Reports

Conduct an investigation of the supporting foundation material and estimate the bearing capacity of the foundation material. Submit the foundation report for all proposed metal box and long span culvert installations with the Stage 1 review.

1008.5 Precast Reinforced Concrete Box Culverts

1008.5.1 Designation

The allowable sizes of Precast reinforced concrete box culverts shall be as given in Figure 1008-14. The pay item description shall include the height of cover (design earth cover), rounded to the highest 1 foot. Structures with a span of 12 feet or less shall be designed as per ASTM C 1577. Structures with spans 14 feet or greater require a special design. CMS Item 706.05 refers to SS 940 which lists the special designs for each span and fill height (design cover).


10-14 January 2015


The maximum allowable height of cover is measured from the top of the culvert to the pavement surface. The maximum height of cover will be limited to 10 feet. Greater covers may be provided contingent upon the approval of the Manufacturer. A special design is required. 1008.5.3 Structural Design Criteria

The design loading information shall be included on the Culvert Detail Sheet or Site Plan. Structures with spans 14 feet or greater are designed with the HL-93 loading. A 60 psf future wearing surface is included in the dead loading only for structures with spans 14’ or greater.

1008.6 Precast Reinforced Concrete Three-Sided Flat-Topped Culverts


Precast reinforced concrete three-sided, flat-topped culverts shall have a minimum clear span of 14 feet and minimum opening rise of 4 feet; and a maximum clear span of 34 feet and maximum opening rise of 10 feet. The individual culvert units may be skewed in 5° increments with a maximum skew of 30°. Designate the skew of the structure relative to the roadway in 1° increments with a maximum skew of 30°. The minimum deck thickness for the culvert units is 12 inches and the minimum leg thickness for the culvert units is 10 inches. The design should be based on these dimensions. 1008.6.2 Height of Cover

The maximum allowable height of cover is measured from the top of the culvert to the pavement surface. The maximum height of cover should be limited to 5 feet. Greater covers may be provided contingent upon the approval of the Manufacturer. 1008.6.3 Structural Design Criteria

Design Flat-topped, three-sided culverts in accordance with AASHTO LRFD Bridge Design Specifications design methodologies. The design loading information (HL-93) shall be included on the Culvert Detail Sheet or Site Plan. Spans greater than 12 feet shall have an additional load of 60 psf to allow for future roadway resurfacing. 1008.6.4 Foundation Reports

Conduct an investigation of the supporting foundation material and estimate the bearing capacity of the foundation material. Submit the foundation report for all proposed flat-topped, three-sided culvert installations with the Stage 1 review. Show the footing and/or pedestal wall vertical and horizontal unfactored reaction forces in the plans. Refer to section 1008.9 for information on foundation types.

1008.7 Precast Reinforced Concrete Arch Sections


Precast reinforced concrete arch sections have a clear span of 12 to 34, 36, 42, 48, 54, 60 feet and an opening rise of 4 feet through 13 feet (maximum). Use of other sizes requires that a Proprietary Waiver


January 2015 10-15

Request (Proprietary Product Approval Request) be completed and signed by the contracting agency. This form may be found at the following web site: http://www.dot.state.oh.us/Divisions/Planning/LocalPrograms/Pages/Local-Let-Procedures-and-Documents.aspx. Designate the skew of the structure relative to the roadway in 1° increments with a maximum skew of 30°. Individual culvert sections may only be skewed with written permission from OHE. Obtain the deck thickness and leg thickness for the culvert units from the manufacturer. Show the maximum and minimum cover on the plans. Design the footing keyway based on the leg thickness plus 6 inches. Design the guardrail post length based on the deck thickness and cover. Precast reinforced concrete arch sections may only be used for roadway grade separation structures with written approval from the OSE. Standard design modifications, including but not limited to increased concrete thickness, concrete admixtures, epoxy coating of concrete surfaces and epoxy coating of reinforcing steel may be required for approval for use as roadway grade separation structures. 1008.7.2 Height of Cover

The maximum allowable height of cover is measured from the top of the culvert to the finished surface. The maximum height of cover is limited to 12 feet. Cover greater than 12 feet may be provided contingent upon the approval of the Manufacturer. The minimum cover, from the top of the arch sections to the top of the pavement is 12 inches. However, in no case shall the top of the arch sections be located above the top of subgrade. 1008.7.3 Structural Design Criteria

Precast Reinforced Concrete Arch Sections are designed in accordance with AASHTO LRFD Bridge Design Specifications design methodologies. Show the design loading information (HL-93) with the future wearing surface load of 60 psf on the Culvert Detail Sheet or Site Plan. 1008.7.4 Foundation Reports

Conduct an investigation of the supporting foundation material and estimate the bearing capacity of the foundation material. Submit the foundation report for all precast reinforced concrete arch section culvert installations with the Stage 1 review. Show the footing and/or pedestal wall vertical and horizontal unfactored reaction forces in the plans. Refer to section 1008.9 for information on foundation types.

1008.8 Precast Reinforced Concrete Round Sections


Precast reinforced concrete round sections are one or two piece structures with a clear span of 12, 16, 20, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78 and 84 feet available in various rises and shapes. Use of other sizes requires that a Proprietary Waiver Request (Proprietary Product Approval Request) be completed and signed by the contracting agency. This form may be found at the following web site: http://www.dot.state.oh.us/Divisions/Planning/LocalPrograms/Pages/Local-Let-Procedures-and-Documents.aspx Designate the skew of the structure relative to the roadway in 1° increments with a maximum skew of 30°. Individual culvert sections may only be skewed with written permission from OSE.

http://www.dot.state.oh.us/Divisions/Planning/LocalPrograms/Pages/Local-Let-Procedures-and-Documents.aspx





10-16 January 2015

Obtain the section thickness for the sections from the manufacturer. Show the maximum and minimum cover on the plans. Design the footing keyway based on the section thickness plus 8 inches. Design the guardrail post length based on the section thickness and cover. Precast reinforced concrete round sections may only be used for roadway grade separation structures with written approval from OHE. Standard design modifications, including but not limited to increased concrete thickness, concrete admixtures, epoxy coating of concrete surfaces and epoxy coating of reinforcing steel may be required for approval for use as roadway grade separation structures. 1008.8.2 Height of Cover

The maximum allowable height of cover is measured from the top of the round sections to the finished surface. The maximum height of cover is limited to 12 feet. Cover greater than 12 feet may be provided contingent upon the approval of the Manufacturer. The minimum cover, from the top of the round sections to the top of the pavement is 12 inches. However, in no case should the top of the arch sections be located above the top of subgrade. 1008.8.3 Structural Design Criteria

Design Precast Reinforced Concrete Round Sections in accordance with AASHTO LRFD Bridge Design Specifications design methodologies. For all spans, show the design loading information (HL-93) with the future wearing surface load of 60 psf on the Culvert Detail Sheet or Site Plan. 1008.8.4 Foundation Reports

Conduct an investigation of the supporting foundation material and estimate the bearing capacity of the foundation material. Submit the foundation report for all precast reinforced concrete round section installations with the Stage 1 review. Include with the foundation report a letter from the manufacturer stating the reactions for foundation design. Show the footing and/or pedestal wall vertical and horizontal unfactored reaction forces in the plans. Refer to section 1008.9 for information on foundation types.

1008.9 Arch or Flat Slab Top Culvert Foundations

Arch or flat slab topped culverts are supported on either spread footings or deep foundations such as piles or drilled shafts. When a series of precast, three-sided structures are used to produce a multiple span structure over a waterway, spread footings are not permitted. Provide a spread footing founded a minimum of 4 feet below the flow line on competent, scour resistant native soils when there is no evidence of stream scour or degradation. Place the top of the footing below the calculated contraction scour. Extend the leg of the culvert in order to lower the footing depth to a maximum bottom depth of seven feet below the thalweg. Use deep foundations for all other cases. Reasonable and prudent hydraulic analysis of a bridge design requires that an assessment be made of the proposed bridge’s vulnerability to undermining due to potential scour. Because of the extreme hazard and economic hardships posed by a rapid bridge collapse, special considerations must be given to selecting appropriate flood magnitudes for use in the analysis. The hydraulics engineer must always be aware of and use the most current scour forecasting technology.

Reference HEC-23, Volume 2, Section 6, Design Guideline 18, to estimate scour depths for three sided

structures, for all flow conditions. Use K r of 0.38, for the riprap sizing equation (18.1). Use Type C Rock


January 2015 10-17

Channel Protection as a minimum. Access and/or download the HEC-23 publication from the

publications section of the http://www.fhwa.dot.gov/engineering/hydraulics/library_listing.cfm . Provide a cost comparison justification study between alternative structure types, including bridges, when utilizing a deep foundation. Submit the cost comparison justification study during the preliminary engineering phase. Provide a keyway in the foundation to set the arch or flat slab topped culverts into. The width of the keyway is a minimum of 6 inches wider than the precast leg (3 inches on both sides of the leg). The depth of the keyway is a minimum of 3 inches.

1008.10 Bridge Foundations

Perform a scour evaluation for all bridges not founded on scour resistant bedrock. When evaluating scour for a replacement structure, review all inspection reports for evidence of stream degradation (lowering of stream bed), scour or previous scour countermeasures. Compute scour depths with the equations in HEC-18 (Hydraulic Engineering Circular No. 18, Pub. No. FHWA NHI 01-001), “Evaluating Scour at Bridges”. Consider scour depth in the design of the substructures and the location of the bottom of footings and minimum tip elevations for piles and drilled shafts. All major rehabilitation work requires a scour evaluation. The scour evaluation may consist of determining what the bridge is founded on. For example, for a bridge rehabilitation, noting that the bridge is founded on scour resistant bedrock or deep foundations to bedrock, would constitute the scour evaluation. As a minimum, piles shall be embedded 15 ft. below the streambed elevation. Provide a narrative of findings and recommended scour counter-measures in the Structure Type Study. Include a statement regarding the susceptibility of the stream banks and flow line to scour, and also the susceptibility of the piers and abutments to scour. 1008.10.1 Scour Design Flood Frequencies Bridge foundations are designed to withstand the effects of scour caused by hydraulic conditions from floods larger than the design flood. The frequencies for the scour design flood and the scour check flood are determined by the hydraulic design flood frequency used to hydraulically size the bridge. Use the following table to determine the flood frequency for scour:

Hydraulic Design Flood Frequency

Scour Design Flood Frequency

Scour Check Flood Frequency

Q10 Q25 Q50

Q25 Q50 Q100

Q50 Q100 Q500

1008.11 Waterproofing Membrane

Apply an external waterproofing membrane to all precast reinforced concrete box culverts, three-sided flat-topped culverts, arch culverts and round sections. Use Item 512 Waterproofing, Type 2 along the vertical sides and Type 2 or 3 across the top of the structure. Type 3 waterproofing shall be used if pavement is to be used directly on top of the structure. Provide an overlap of a minimum of 12 inches of the top membrane to the vertical membrane.

http://www.fhwa.dot.gov/engineering/hydraulics/library_listing.cfm


10-18 January 2015

1008.12 Precast Reinforced Concrete Flat Slab Tops, Catch Basin Tops, and Inlet Tops

Precast Reinforced Concrete Flat Slab Tops, Catch Basin Tops, and Inlet Tops shall be designed in accordance with ASTM C478. When the structure is under pavement and the span is greater than 10 feet, the design loading for the structural design shall be HL-93.

1008.13 Wingwall Design

When not using the standard construction drawings or design data sheets, design wingwalls in accordance to the current AASHTO LRFD Bridge Design Specifications. Assume no passive forces are acting on the toe of the wall.

1009 Subsurface Pavement Drainage

1009.1 General

Subsurface pavement drainage is required on all projects. An exception may be made where the project is located in an area having a granular subgrade. The subsurface drainage design shall be submitted with the Preliminary Drainage review for approval.

1009.2 Types of Subsurface Drainage

There are three means of draining the pavement subsurface - pipe underdrains, prefabricated edge drains, and aggregate drains. Generally, pipe underdrains are used with paved shoulders and curbed pavements (Figures 1009-1 through 1009-7 and 1009-11). Prefabricated edge drains are typically used where existing concrete pavement with paved shoulders are to remain. Aggregate drains are used with bituminous surface treated shoulders, aggregate shoulders, and for spot improvements (Figures 1009-8 and 1009-9). Additional examples of typical underdrain and edge drain placements can be found in the Sample Plan Sheets. 1009.2.1 Pipe Underdrains

Pipe underdrains are used on both sides of the pavement and are typically carried through super elevated sections. Pipe underdrains are not required within the limits of the MSE wall select granular backfill. The maximum pavement width for each pipe underdrain is 24 feet. Figures 1009-1 through 1009-7 show locations for pipe underdrains with respect to several shoulder designs. Figure 1009-11 shows locations of pipe underdrains through a superelevated section.

Pipe underdrains generally follow the profile grade of the roadway as long as the pipe underdrain maintains a positive or zero slope. For these cases, hydrostatic pressure is sufficient to ensure the proper drainage of the subbase and subgrade. Underdrain depth is measured from the bottom of subbase to the bottom of the underdrain trench. Base pipe and shallow pipe underdrains are typically 4-6 inches in diameter. The 4 and 6 inch underdrains are considered equivalent in hydraulic capacity for the base pipe and shallow pipe underdrains. Use a 6 inch underdrain if the outlet interval is greater than 500 feet or if the subgrade is saturated. Base pipe underdrain has a constant depth of 18 inches or less and the shallow pipe underdrain has a depth greater than 18 inches with a maximum of 30 inches. Where a dual underdrain system is provided (shoulder greater than or equal to 8 feet), the edge of shoulder underdrain is supplemental to the edge of pavement underdrain and is typically a base pipe underdrain with a depth of 18 inches. If dual underdrains are being provided on a super elevated section, the edge of pavement underdrain is not required on the high side.


January 2015 10-19

Rock cut underdrains are used in cut sections when a rock, shale, or coal subgrade exists. The depth of the rock cut underdrain should be 6 inches below the cut surface of the rock (Figure 1009-10). Deep pipe underdrains have a constant depth greater than 30 inches with the maximum depth at 50 inches below subbase. These are typically 6 inches in diameter. Deep pipe underdrains are used in cut sections, or areas with a high water table, to drain the subgrade. Unclassified underdrains are those having a variable depth below profile grade within a single continuous longitudinal run. Variable depth pipe underdrains (unclassified) shall be avoided where pipe underdrains of a constant depth can be provided. Underdrains which outlet to a slope should be provided with an outlet per SCD DM-1.1. Underdrain outlets should be provided at a desirable interval of 500 feet with a maximum interval of 1000 feet. Underdrain outlets should be provided at a desirable interval of 300 feet, with a maximum interval of 500 feet, where free draining base is utilized. It is desirable to outlet underdrains at least 12 inches above the flow line of a receiving ditch; and 12 inches above the flow line of a receiving catch basin, manhole, or pipe with 6 inches as a minimum. Underdrain outlets shall be type F conduit. When underdrain spans the trench of a lower conduit (utility, storm sewer, culvert, etc.) and the vertical distance between the trench and underdrain is less than or equal to 12 inches, a type F conduit should be used to span the lower trench. Use a minimum of 10 feet. A fabric filter wrap should be used when existing soils consist of a sandy or sandy-silt composition. Where necessary, the depth of the underdrains may vary slightly. Underdrain outlet pipe outletting into a roadway ditch or fill slope should maintain a minimum slope of 1%. Outlets should not be located at the top of high (over 20 feet) 2:1 fill slopes. If this cannot be accomplished by adjusting the spacing, special outlet treatments will be required. 1009.2.2 Construction Underdrains

In fine-grained soils excess water in the subgrade is the principal cause of unstable soil conditions during construction. Adequate subgrade drainage can be achieved by using temporary pipe underdrains. These underdrains are sacrificial in nature and are intended to work throughout the construction process. Construction Underdrains are usually placed in the centerline of the roadway. They may also be placed in the ditch line, if the water is coming in from a cut section at a higher elevation. The outlets for the construction underdrains are the same pipe material and backfill as construction underdrains (not Type F). The outlets should be discharged into a catch basin, manhole, pipe, or ditch. If discharging into a ditch, a precast concrete reinforced outlet is not required. 1009.2.3 Prefabricated Edge Drains

Prefabricated edge drains are located at the edge of existing concrete pavement on resurfacing projects where the existing pavement and paved shoulders are being retained. If existing paved shoulders are being replaced, a 4 inch shallow pipe underdrain at the edge of pavement shall be used in lieu of the prefabricated edge drain. 1009.2.4 Aggregate Drains

Aggregate drains should be located at 50 foot intervals on each side of the pavement and staggered so that each drain is 25 feet longitudinally apart from the adjacent drain on the opposite side. If used on rigid pavements, the drains shall be located at each end of each transverse joint. For superelevated pavements, the drains should be located on the low side only, at each transverse joint in rigid pavement


10-20 January 2015

and at 25 foot intervals for other pavement. Figures 1009-8 and 1009-9 show aggregate drains for several treated shoulder designs.

1010 Maintenance of Traffic Drainage

1010.1 General

Positive drainage during Maintenance of Traffic (MOT) operations is furnished under items 614 and 615 of the CMS for most projects. Evaluate MOT drainage for projects on Interstates and Expressways that have one or more of the following or as directed by the District: A. Multi-phased MOT operations

B. Profile changes in the roadway that temporarily create a sag point different than the final design

C. Traffic maintained adjacent to concrete barrier with less than 2 feet clear distance from the edge of

lane to the edge of barrier Furnish a minimum dry lane width of 10 feet for each travelled lane. Determine the spread of water on the pavement using a 2 year design frequency unless a different frequency is specified by the District. Provide MOT drainage by utilizing permanent drainage items for final design and temporary drainage items. Temporary drainage items may include items such as inlets, storm sewers, culverts, ditches, perforated conduits, catch basins, conduits jacked and bored, opening cuts in concrete barrier, French drains, pavement saw cut openings, etcetera. These drainage items may conflict with future MOT phases and may require removal quantities in subsequent MOT phases. Use permanent drainage items for final design where feasible. Furnish a minimum diameter of 12 inches for temporary storm sewer and 18 inches for temporary culverts. Provide temporary drainage items on the MOT plan per plan note D124.

1011 Temporary Structures

The design year and other hydraulic requirements for temporary structures are defined in CMS 502.02. Ensure scour depth is accounted for in the in the design of a temporary bridge and foundation. Show the water surface elevation (“high water”) and velocity of the design year discharge on the temporary structure plans. Ensure the design year discharge does not contact the lowest portion of the superstructure of a temporary bridge. Culvert pipes may be used in lieu of a bridge structure provided controls specified in Section 1006 are not exceeded for the design year discharge. Refer to Section 500 of the Bridge Design Manual for other details regarding temporary structures.

1000 Drainage Design Criteria – List of Figures

January 2015

Figure Subject 1002-1 Minimum Culvert Sizes 1002-2 Water pH Contours - Average for Counties 1002-3 Water pH Contours - Values of Individual Culverts 1002-4 Requirements for Concrete Pipe Protection General Notes for Figures 1002-5 and 1002-6 1002-5(50) Requirements for Corrugated Metal Pipe Thickness and Protection at Non-Abrasive Sites - 50-year Design Service Life 1002-5(75) Requirements for Corrugated Metal Pipe Thickness and Protection at Non-Abrasive Sites - 75-year Design Service Life 1002-6(50) Requirements for Corrugated Metal Pipe Thickness and Protection at Abrasive Sites - 50-year Design Service Life 1002-6(75) Requirements for Corrugated Metal Pipe Thickness and Protection at Abrasive Sites - 75-year Design Service Life 1006-1 Floodway Schematic General Notes for Figures 1008-1 through 1008-9 1008-1 Minimum Height of Cover - Corrugated Steel Pipe 1008-2 Minimum Height of Cover - Corrugated Steel Pipe Arches 1008-3 Minimum Height of Cover - Structural Plate Corrugated Steel Pipe 1008-4 Minimum Height of Cover - Structural Plate Corrugated Steel Pipe Arches (18-inch Corner Radius) 1008-5 Minimum Height of Cover - Structural Plate Corrugated Steel Pipe-Arches (31-inch Corner Radius) 1008-6 Minimum Height of Cover - Corrugated Steel Spiral Rib Pipe 1008-7 Table Deleted January 2013 1008-8 Table Deleted January 2013 1008-9 Table Deleted January 2013 General Notes for Figures 1008-10 through 1008-14 1008-10 Table Deleted January 2013 1008-11 Reinforced Concrete Circular Pipe

1000 Drainage Design Criteria – List of Figures

January 2015

Figure Subject 1008-12 Reinforced Concrete Elliptical Pipe 1008-13 Table Deleted January 2013 1008-14 Maximum Allowable Height of Cover - Reinforced Concrete Box Culverts General Notes for Figures 1008-15 through 1008-21 1008-15 Minimum Height of Cover - Corrugated Aluminum Pipe 1008-16 Minimum Height of Cover - Corrugated Aluminum Pipe Arches 1008-17 Minimum Height of Cover - Structural Plate Corrugated Aluminum Pipe 1008-18 Minimum Height of Cover - Structural Plate Corrugated Aluminum Pipe Arches 1008-19 Minimum Height of Cover - Corrugated Aluminum Spiral Rib Pipe 1008-20 Table Deleted January 2013 1008-21 Table Deleted January 2013 1009-1 Typical Pipe Underdrain Locations 1009-2 Typical Pipe Underdrain Locations 1009-3 Typical Pipe Underdrain Locations 1009-4 Typical Pipe Underdrain Locations 1009-5 Typical Pipe Underdrain Locations 1009-6 Typical Pipe Underdrain Locations 1009-7 Typical Pipe Underdrain Locations 1009-8 Typical Aggregate Drain Locations 1009-9 Typical Aggregate Drain Locations

1009-10 Typical Rock Cut Underdrain

1009-11 Typical Pipe Underdrain Locations

General Notes – Figures 1002-5 and 1002-6

Tables 1002-5(50) & 1002-5(75) Tables 1002-5(50) and 1002-5(75) are based on equations 6 and 8 from the ODOT Location & Design publication 82-1, “Culvert Durability Study” including:

A 15-year service life for Bituminous Coating with Invert Paving for culverts 54” and larger.

A 25-year service life for Bituminous Coating with Invert Paving for culverts 48” and smaller.

A 35-year service life for Aluminum Coating with pH above 5.0

A 50-year service life for Polymeric Coating

All base metals must provide a minimum of 10 years of service life. Corrugated aluminum alloy pipe (707.21 and 707.22) and aluminum alloy structural plate pipe (707.23) are acceptable with the minimum thickness required to satisfy cover conditions for all non-abrasive sites with a pH between 5.0 and 9.0 A blank space in the table indicates that a gage, which satisfies the design service life, is not available.

Tables 1002-6(50) & 1002-6(75) Tables 1002-6(50) and 1002-6(75) are based on equations 7 and 9 from the ODOT Location & Design publication 82-1, “Culvert Durability Study” including:

A 15-year service life for Bituminous Coating with Invert Paving for culverts 54” and larger.

A 25-year service life for Bituminous Coating with Invert Paving for culverts 48” and smaller.

A 35-year service life for Aluminum Coating with pH above 5.0.

A 50-year service life for Polymeric Coating

All base metals must provide a minimum of 10 years of service life.

Corrugated aluminum alloy pipe (707.21 and 707.22) with Concrete Field Paving and aluminum alloy structural plate pipe (707.23) with Concrete Field Paving are acceptable with the minimum thickness required to satisfy cover conditions for all abrasive sites with a pH between 5.0 and 9.0 A blank space in the table indicates that a gage, which satisfies the design service life, is not available.

Abbreviations and Symbols * Concrete field paving shall be epoxy coated per 706.03 for pH < 5.0 ** Externally coated per AASHTO M243 w/CFP With concrete field paving of invert

General Notes - Figures 1008-1 through 1008-9

Thickness The following table shows the available commercial thicknesses for metallic coated steel and the corresponding gage number:

0.064

0.079

0.109

0.138

16

14

12

10

0.168 8

0.188 7

0.218 5

0.249 3

0.280 1

The maximum available sheet thickness for aluminum coated corrugated steel pipe (707.01, 707.02, 707.05, 707.07; all with aluminum coating) or polymer coated corrugated steel pipe (707.04) is 0.138.

Minimum Cover The minimum cover is measured from the top of the pipe or pipe-arch to the top of subgrade; however, in no installation shall the distance from the top of the pipe or pipe-arch to the top of the wearing surface or finished grade be less than the figure values plus 6 inches.

Maximum Cover The maximum height of cover is measured from the top of the pipe or pipe-arch, to the top of the wearing surface

Metal Thickness Inches

Gage Number

Pipe Diameter

(inches)

12

15

18

21

24

27

30

36

42

48

54

60

66

72

78

84

36

42

48

54

60

66

72

78

84

90

96

102

108

114

120

Minimum Cover

18

MINIMUM HEIGHT OF COVER TABLE 1CORRUGATED STEEL PIPE

1008-1

Pipe

Des

igna

tion

HEIGHT OF COVER TABLE 1

(inches)

12

12

18

12

Revised July 2014

Corrugated Steel Pipe

Reference Section1008.1.2

12

12

12

12

12

12

12

12

12

12

12

18

12

12

12

12

12

12

18

707.

01, 7

07.0

4, 7

07.0

5, 7

07.1

1 an

d 70

7.13

(2

2/3

" x 1

/2" C

orru

gatio

ns)

707.

02, 7

07.0

4, 7

07.0

7, 7

07.1

1 an

d 70

7.14

(5" x

1" C

orru

gatio

ns)

12

12

12

12

12

12

12

Pipe DimentionsSpan X Rise

(inches)

17 x 13

21 x 15

24 x 18

28 x 20

35 x 24

42 x 29

49 x 33

57 x 38

64 x 43

71 x 47

77 x 52

83 x 57

40 x 31

46 x 36

53 x 41

60 x 46

66 x 51

73 x 55

81 x 59

87 x 63

95 x 67

103 x 71

112 x 75

117 x 79

128 x 83

137 x 87

142 x 91

Revised July 2014

1008-2Reference Section

1008.1.2

Pipe

12

12

(inches)

12

12

Corrugated Steel Pipe Arches

Minimum Cover

15

15

15

15

12

12

12

18

18

21

18

18

18

24

707.

01, 7

07.0

4, 7

07.0

5, 7

07.1

1 an

d 70

7.13

(2 2

/3" x

1/2

" Cor

ruga

tions

)70

7.02

, 707

.04,

707

.07,

707

.11

and

707.

14

(5" x

1" C

orru

gatio

ns)

21

24

24

MINIMUM HEIGHT OF COVER TABLE 2 CORRUGATED STEEL PIPE ARCHES

Pipe

Des

igna

tion


12

15

12

12

12

12

Pipe Pipe Diameter Diameter

(inches) (feet-inches)

60 5'0"

66 5'6"

72 6'0"

78 6'6"

84 7'0"

90 7'6"

96 8'0"

102 8'6"

108 9'0"

114 9'6"

120 10'0"

126 10'6"

132 11'0"

138 11'6"

144 12'0"

150 12'6"

156 13'0"

162 13'6"

168 14'0"

174 14'6"

180 15'0"

186 15'6"

192 16'0"

198 16'6"

204 17'0"

210 17'6"

216 18'0"

222 18'6"

228 19'0"

234 19'6"

240 20'0"

246 20'6"

252 21'0"

Revised July 2014


1008.1.2


707.03 Structural Plate Corrugated Steel Pipe

Minimum Cover

(inches)

12

12

12

12

12

12

12

18

18

18

18

18

18

18

18

30

24

24

24

24

24

24

24

24

30

36

30

30

30

30

30

MINIMUM HEIGHT OF COVER TABLE 3 707.03 STRUCTURAL PLATE CORRUGATED

STEEL PIPE

36

30

Pipe

Dimentions

Span X Rise

(feet-inches)

6'1" x 4'7"

6'4" x 4'9"

6'9 x 4'11"

7'0" x 5'1"

7'3" x 5'3"

7'8" x 5'5"

7'11" x 5'7"

8'2" x 5'9"

8'7" x 5'11"

8'10" x 6'1"

9'4" x 6'3"

9'6" x 6'5"

9'9" x 6'7"

10'3" x 6'9"

10'8" x 6'11"

10'11" x 7'1"

11'5" x 7'3"

11'7" x 7'5"

11'10" x 7'7"

12'4" x 7'9"

12'6" x 7'11"

12'8" x 8'1"

12'10" x 8'4"

13'5" x 8'5"

13'11" x 8'7"

14'1" x 8'9"

14'3" x 8'11"

14'10" x 9'1"

15'4" x 9'3"

15'6" x 9'5"

15'8" x 9'7"

15'10" x 9'10"

16'5" x 9'11"

16'7" x 10'1"

Revised January 2013

MINIMUM HEIGHT OF COVER TABLE 4

707.03 STRUCTURAL PLATE

CORRUGATED STEEL PIPE ARCHES

1008-4

Reference Section

1008.1.2


707.03 Structural Plate Corrugated Steel Pipe (18-inch Corner Radius)

Minimum Cover

(inches)

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

24

24

24

24

24

24

24

24

24

24

36

36

24

Pipe

Dimentions

Span X Rise

(feet-inches)

13'3" x 9'4"

13'6" x 9'6"

14'0" x 9'8"

14'2" x 9'10"

14'5" x 10'0"

14'11" x 10'2"

15'4" x 10'4"

15'7" x 10'6"

15'10" x 10'8"

16'3" x 10'10"

16'6" x 11'0"

17'0" x 11'2"

17'2" x 11'4"

17'5" x 11'6"

17'11" x 11'8"

18'1" x 11'10"

18'7" x 12'0"

18'9" x 12'2"

19'3" x 12'4"

19'6" x 12'6"

19'8" x 12'8"

19'11" x 12'10"

20'5" x 13'0"

20'7" x 13'2"



707.03 STRUCTURAL PLATE CORRUGATED

STEEL PIPE ARCHES

1008-5

Reference Section

1008.1.2


707.03 Structural Plate Corrugated Steel Pipe (31-inch Corner Radius)

Minimum Cover

(inches)

24

24

24

24

24

24

24

24

24

36

36

36

36

36

36

36

36

36

36

36

36

36

36

36

Pipe

Diameter

(inches)

18

21

24

30

36

42

48

54

60

66

72

78

84

90


Reference Section

1008.1.2


Corrugated Steel Spiral Rib Pipe


FOR CORRUGATED STEEL

SPIRAL RIB PIPE

1008-6

707.12

(3/4" x 7 1/2" Corrugations)

18

18

18

12

12

18

18

15

15

15

15

(inches)

12

12

12

Pipe

Designation

Minimum Cover


Minimum Cover

See Section 1008.2.2

Maximum Cover The maximum height of cover is measured from the top of the pipe or elliptical pipe to the top of the wearing surface.

Pipe

Diameter

(inches)

12

15

18

21

24

27

30

36

42

48

54

60

66

72

78

84

90

96

102

108

114

120

126

132

144

4

2.5

2.75

3

3.25

3.5

7.5

4.5

5

5.5

6

6.5

7

8.5

9

9.5

10.5

11

12

(inches)

2

2.25

8

8

8.5


REINFORCED CONCRETE

CIRCULAR PIPE

1008-11

Reference Section

1008.2.1

706.02 Reinforced Concrete Circular Pipe

Wall Thickness

10

Equivalent Pipe Equivalent Pipe

Round Rise X Span Round Rise X Span

Diameter Diameter

(inches) (inches) (inches) (inches) (inches) (inches)

18 14x23 2.75 36 45x29 4.5

24 19x30 3.25 42 53x34 5

27 22x34 3.5 48 60x38 5.5

30 24x38 3.75 54 68x43 6

36 29x45 4.50 60 76x48 6.5

42 34x53 5 66 83x53 7

48 38x60 5.5 72 91x58 7.5

54 43x68 6 78 98x63 8

60 48x76 6.5 84 106x68 8.5

66 53x83 7 90 113x72 9

72 58x91 7.5 96 121x77 9.5

78 63x98 8 102 128x82 9.75

84 68x106 8.5 108 136x87 10

90 72x113 9 114 143x92 10.5

96 77x121 9.5 120 151x97 11

102 82x128 9.75 132 166x106 12

108 87x136 10 144 180x116 13

114 92x143 10.5

120 97x151 11

132 106x166 12

144 116x180 13

Wall

Thickness

Wall

Thickness


REINFORCED CONCRETE

ELLIPTICAL PIPE

1008-12

Reference Section

1008.2.1

706.04 Reinforced Concrete Elliptical Pipe

Box

Span 4 5 6 7 8 9 10

(ft)

8 10 10 10 10 - - -

10 - 10 10 10 10 10 -12 10 - 10 - 10 - 10

14 10 10 10 10 10 10 10

16 10 10 10 10 10 10 10

18 10 10 10 10 10 10 10

20 10 10 10 10 10 10 10



1008.5

MAXIMUM ALLOWABLE HEIGHT OF COVER - REINFORCED CONCRETE

BOX CULVERTS

706.05 Precast Reinforced Concrete Box Culverts

Box Rise (ft)

*Height of Fill (Maximum)

Approval of OHE is required for sizes other than those listed above.

Spans 14' or greater shall be designed for HL93 live load with an additonal 60psf for a future wearing surface.


Thickness The following table shows the available commercial metal thicknesses for aluminum pipe:

Metal Thickness Inches

707.21, 707.22 & 707.24

Metal Thickness Inches 707. 23

0.060 0.075 0.105 0.135 0.164

0.100 0.125 0.150 0.175 0.200 0.225 0.250

Minimum Cover

The minimum cover is measured from the top of the pipe or pipe arch to the top of subgrade; however, in no installation shall the distance from the top of the pipe or pipe arch to the top of the wearing surface or finished grade be less than the figure values plus 6 inches.

Maximum Cover

The maximum height of cover is measured from the top of the pipe or pipe arch to the top of the wearing surface.


1100 Drainage Design Procedures 1101 Estimating Design Discharge .......................................................................................................... 11-1

1101.1 General ........................................................................................................................... 11-1 1101.2 Procedures ...................................................................................................................... 11-1

1101.2.1 Statistical Methods .......................................................................................... 11-1 1101.2.2 Rational Method .............................................................................................. 11-1 1101.2.3 Coefficient of Runoff ....................................................................................... 11-3 1101.2.4 Rainfall Intensity .............................................................................................. 11-4

1102 Open Water Carriers ....................................................................................................................... 11-4 1102.1 General ........................................................................................................................... 11-4 1102.2 Types of Carriers............................................................................................................. 11-5

1102.2.1 Standard Roadway (Roadside) Ditches .......................................................... 11-5 1102.2.2 Special Ditches ............................................................................................... 11-5 1102.2.3 Median Ditches ............................................................................................... 11-5 1102.2.4 Channel Relocations ....................................................................................... 11-5 1102.2.5 Channel Linings and Bank Stabilization ......................................................... 11-6

1102.3 Ditch Design Criteria - Design Traffic Exceeding 2000 ADT .......................................... 11-6 1102.3.1 Design Frequency ........................................................................................... 11-6 1102.3.2 Ditch Protection ............................................................................................... 11-6 1102.3.3 Roughness ...................................................................................................... 11-8 1102.3.4 Catch Basin Types .......................................................................................... 11-9 1102.3.5 Calculated Catch Basin Spacing .................................................................... 11-9 1102.3.6 Arbitrary Maximum Catch Basin Spacing ..................................................... 11-10

1102.4 Ditch Design Criteria - Design Traffic of 2000 ADT or Less ......................................... 11-10 1102.4.1 Design Frequency ......................................................................................... 11-10 1102.4.2 Shear Stress Protection ................................................................................ 11-10 1102.4.3 Roughness .................................................................................................... 11-10 1102.4.4 Catch Basin Types ........................................................................................ 11-11

1102.5 Design Aids for Ditch Flow Analysis ............................................................................. 11-11 1102.5.1 Earth Channel Charts ................................................................................... 11-11 1102.5.2 Rectangular Channel Charts......................................................................... 11-11

1103 Pavement Drainage ...................................................................................................................... 11-11 1103.1 General ......................................................................................................................... 11-11 1103.2 Design Frequency ......................................................................................................... 11-12 1103.3 Estimating Design Discharge ........................................................................................ 11-12 1103.4 Capacity of Pavement Gutters ...................................................................................... 11-12 1103.5 Pavement Flow Charts .................................................................................................. 11-13 1103.6 Bypass Charts for Continuous Pavement Grades ........................................................ 11-13

1103.6.1 Curb Opening Inlets ...................................................................................... 11-14 1103.6.2 Grate or Combination Grate and Curb Opening Inlet ................................... 11-14

1103.7 Grate Catch Basins and Curb Opening Inlets in Pavement Sags ................................ 11-14 1103.8 Bridge Deck Drainage ................................................................................................... 11-14 1103.9 Slotted Drains and Trench Drains ................................................................................. 11-15

1104 Storm Sewers ................................................................................................................................ 11-15 1104.1 General ......................................................................................................................... 11-15 1104.2 Design Considerations .................................................................................................. 11-16

1104.2.1 Storm Sewer Depth ....................................................................................... 11-16 1104.2.2 Storm Sewer Access ..................................................................................... 11-17 1104.2.3 Rock Excavation for Storm Sewer ................................................................ 11-17

1104.3 Layout Procedure .......................................................................................................... 11-18 1104.3.1 Plan ............................................................................................................... 11-18 1104.3.2 Profile ............................................................................................................ 11-18

1104.4 Storm Sewer Design Criteria ........................................................................................ 11-18 1104.4.1 Design Frequency ......................................................................................... 11-18

1104.4.2 Hydraulic Grade Line .................................................................................... 11-18 1104.4.3 Coefficient of Runoff ..................................................................................... 11-19 1104.4.4 Time of Concentration ................................................................................... 11-19 1104.4.5 Pipe Roughness Coefficient.......................................................................... 11-19 1104.4.6 Minimum Storm Sewer Pipe Size ................................................................. 11-19 1104.4.7 Maximum Storm Sewer Slope ...................................................................... 11-19

1104.5 Hydraulic Design Procedure ......................................................................................... 11-19 1104.6 Combined Sanitary Sewer Separation .......................................................................... 11-20

1105 Roadway Culverts ......................................................................................................................... 11-20 1105.1 General ......................................................................................................................... 11-20 1105.2 Stream Protection ......................................................................................................... 11-20

1105.2.1 Bankfull Discharge Design ............................................................................ 11-21 1105.2.2 Depressed Culvert Inverts ............................................................................ 11-22 1105.2.3 Paved Depressed Approach Aprons ............................................................ 11-23 1105.2.4 Flood Plain Culverts ...................................................................................... 11-23 1105.2.5 Energy Control Structures ............................................................................. 11-24

1105.3 Types of Culvert Flow ................................................................................................... 11-24 1105.4 Design Procedure ......................................................................................................... 11-24

1105.4.1 General ......................................................................................................... 11-24 1105.4.2 Hydraulic Analysis ......................................................................................... 11-24

1105.5 Use of Nomographs ...................................................................................................... 11-25 1105.5.1 Outlet Control ................................................................................................ 11-25 1105.5.2 Inlet Control ................................................................................................... 11-25

1105.6 Design Criteria .............................................................................................................. 11-26 1105.6.1 Design Frequency ......................................................................................... 11-26 1105.6.2 Maximum Allowable Headwater.................................................................... 11-26 1105.6.3 Method Used to Estimate Storm Discharge .................................................. 11-26 1105.6.4 Scale of Topographic Mapping Used to Delineate Contributing Drainage Areas ..................................................................................................................................... 11-26 1105.6.5 Manning’s Roughness Coefficient “n” ........................................................... 11-26 1105.6.6 Entrance Loss Coefficient “ke” ...................................................................... 11-26 1105.6.7 Minimum Cover ............................................................................................. 11-26 1105.6.8 Maximum Cover ............................................................................................ 11-26 1105.6.9 Maximum Allowable Outlet Velocity .............................................................. 11-27 1105.6.10 Headwall Type ............................................................................................ 11-27 1105.6.11 Contacts With County Engineer .................................................................. 11-27 1105.6.12 Minimum Pipe Size ..................................................................................... 11-27 1105.6.13 Ordinary High Water Mark .......................................................................... 11-27

1105.7 Special Considerations ................................................................................................. 11-27 1105.7.1 Tailwater........................................................................................................ 11-27 1105.7.2 Multiple Cell Culverts .................................................................................... 11-28 1105.7.3 Improved Inlets ............................................................................................. 11-28

1106 End Treatments ............................................................................................................................. 11-28 1106.1 General ......................................................................................................................... 11-28

1106.1.1 Usage ............................................................................................................ 11-28 1106.1.2 End Treatment Grading ................................................................................ 11-29

1106.2 Headwall Types............................................................................................................. 11-29 1106.2.1 Half-Height Headwalls .................................................................................. 11-29 1106.2.2 Full-Height Headwalls ................................................................................... 11-29

1106.3 Concrete Apron ............................................................................................................. 11-30 1107 Rock Channel Protection (RCP) ................................................................................................... 11-30

1107.1 General ......................................................................................................................... 11-30 1107.2 Culvert RCP Types ....................................................................................................... 11-30 1107.3 Bridge RCP ................................................................................................................... 11-30

1108 Agricultural Drainage..................................................................................................................... 11-31 1108.1 Farm Drain Crossings ................................................................................................... 11-31 1108.2 Farm Drain Outlets ........................................................................................................ 11-31

1109 Longitudinal Sewer Location ......................................................................................................... 11-31

1109.1 Under Pavement ........................................................................................................... 11-31 1109.2 Under Paved Shoulder .................................................................................................. 11-31 1109.3 Approval ........................................................................................................................ 11-32

1110 Reinforced Concrete Radius Pipe and Box Sections ................................................................... 11-32 1110.1 General ......................................................................................................................... 11-32

1111 Sanitary Sewers ............................................................................................................................ 11-32 1111.1 General ......................................................................................................................... 11-32 1111.2 Manholes ....................................................................................................................... 11-32

1112 Notice of Intent (NOI) .................................................................................................................... 11-32 1112.1 General ......................................................................................................................... 11-32 1112.2 Routine Maintenance Project ........................................................................................ 11-33 1112.3 Watershed Specific NOI Requirements ........................................................................ 11-34

1113 Erosion Control at Bridge Ends ..................................................................................................... 11-35 1113.1 General ......................................................................................................................... 11-35 1113.2 Corner Cone .................................................................................................................. 11-35

1114 Temporary Sediment and Erosion Control ................................................................................... 11-35 1114.1 General ......................................................................................................................... 11-35 1114.2 Cost Estimate for Temporary Sediment and Erosion Control ....................................... 11-35

1115 Post Construction Storm Water Structural Best Management Practices ...................................... 11-35 1115.1 General ......................................................................................................................... 11-35 1115.2 Project Thresholds for Post-Construction BMP ............................................................ 11-36 1115.3 Water Quality and Water Quantity Treatment ............................................................... 11-37 1115.4 Water Quality Volume ................................................................................................... 11-37 1115.5 Water Quality Flow ........................................................................................................ 11-38 1115.6 Project Type - Redevelopment and New Construction ................................................. 11-38

1115.6.1 Redevelopment Projects ............................................................................... 11-38 1115.6.2 New Construction Projects ............................................................................ 11-38 1115.7 Treatment Requirements for Projects .............................................................. 11-39

1116 BMP Selection and Submittals ...................................................................................................... 11-40 1116.1 BMP Selection............................................................................................................... 11-40 1116.2 BMP Submittals............................................................................................................. 11-40

1117 BMP Toolbox ................................................................................................................................. 11-41 1117.1 Manufactured Systems ................................................................................................. 11-41 1117.2 Vegetation Based BMP ................................................................................................. 11-42

1117.2.1 Vegetated Filter Strip .................................................................................... 11-42 1117.2.2 Vegetated Biofilter ......................................................................................... 11-43

1117.3 Extended Detention ...................................................................................................... 11-44 1117.3.1 Detention Basin ............................................................................................. 11-45 1117.3.2 Underground Detention ................................................................................. 11-47 1117.3.3 Design Check Discharge .............................................................................. 11-48

1117.4 Retention Basin ............................................................................................................. 11-48 1117.4.1 Water Quality Basin and Weir ....................................................................... 11-49

1117.5 Bioretention Cell ............................................................................................................ 11-49 1117.6 Infiltration ....................................................................................................................... 11-50

1117.6.1 Infiltration Trench .......................................................................................... 11-51 1117.6.2 Infiltration Basin ............................................................................................ 11-52

1117.7 Constructed Wetlands ................................................................................................... 11-54 1118 Bridge Hydraulics .......................................................................................................................... 11-54

1118.1 General ......................................................................................................................... 11-54 1118.2 Hydrology and Hydraulics (H&H) Report ...................................................................... 11-55

1118.2.1 Analysis ......................................................................................................... 11-55 1118.2.2 Narrative........................................................................................................ 11-55

1100 Drainage Design Procedures 1101 Estimating Design Discharge

1101.1 General

In order to properly design highway drainage facilities, it is essential that a reasonable estimate be made of the design and check discharges. Some of the more important factors affecting runoff are duration, intensity and frequency of rainfall; and the size, imperviousness, slope, and shape of the drainage area. Use suitable topographic mapping to determine the contributing drainage area. For drainage areas over 100 acres, a 7.5 minute U.S. Geological Survey Quadrangle will ordinarily suffice. For smaller areas, or where discharges are calculated using the rational method, smaller scale maps (1”=50’ to 1”=800’) may be more appropriate. Other methods that use Geographic Information Systems (GIS) such as USGS Stream Stats are acceptable. The use of contours generated from LiDAR data collected through the Ohio Statewide Imagery Program (OSIP) is also acceptable. LiDAR tools are available through GEOPAK to facilitate the use of LiDAR data. Consult the ODOT GEOPAK V8i LiDAR Tools User Guide at: http://www.dot.state.oh.us/Divisions/Engineering/Production/CADD/Pages/GPKManual.aspx A proper evaluation should be made of the land use throughout the drainage area. Changes in land use within the drainage area which will occur in the immediate future shall be taken into account when determining design discharges. However, probable land use changes beyond this should not be assumed when determining design discharges. It is the responsibility of the local permitting/zoning agency to ensure proper land and water management techniques are utilized. These techniques will minimize the adverse effects of a change in land use. Post Construction Storm Water Best Management Practices are used on roadway projects in an effort to minimize quality and quantity impacts as well (see section 1115). 1101.2 Procedures

1101.2.1 Statistical Methods

See Section 1003. 1101.2.2 Rational Method

The rational method is considered to be more reliable for estimating runoff from small drainage areas, less than the acreage for the USGS Regions; and for areas that contribute overland flow and shallow concentrated flow to the roadway ditch or pavement. The design discharge “Q” is obtained from the equation:

Q = CiA where: Q = Discharge in cubic feet per second

C = Coefficient of runoff

I = Average rainfall intensity in inches per

hour, for a given storm frequency and for a duration equal to the time of concentration.

A = Drainage area in acres

January 2015 11-1

http://www.dot.state.oh.us/Divisions/ProdMgt/Production/CADD/Pages/GPKManual.aspx

Drainage Design Procedures The time of concentration is the time required for runoff to flow from the most remote point of the drainage area to the point of concentration. The point of concentration could be a culvert, catch basin or the checkpoint in a roadway ditch used to determine the need for velocity protection. Time of concentration is designated by “tc” and is the summation of the time of overland flow “to”, the time of shallow concentrated flow "ts" and the time of pipe or open channel flow “td”. Overland flow is that flow which is not carried in a discernible channel and maintains a uniform depth across the sloping surface. It is often referred to as sheet flow. The time of overland flow may be obtained from Figure 1101-1, a similar overland flow chart, or from the equation:

to ≈ 1.8(1.1-C) (L)(1/2)

(s)(1/3)

where: to = Time of overland flow in minutes

C = Coefficient of runoff

L = Distance to most remote location in

drainage area in feet (300 ft. max)

s = Overland slope (percent)

These methods should not be used to determine the time of travel for gutter, swale, or ditch flow. This equation and Figure 1101-1 assume a homogeneous drainage area. Where the overland flow area is composed of segments with varying cover and/or slopes, the summation of the time of concentration for each segment will tend to over-estimate the overland flow time, “to”. In this case it may be more appropriate to use an average runoff coefficient "C" and an average ground slope in the Overland Flow Chart. Sheet flow is assumed to occur for no more than 300 feet after which water tends to concentrate in rills and then gullies of increasing proportion. This type of flow is classified as shallow concentrated flow. The velocity of shallow concentrated flow can be estimated using the following relationship:

V = 3.281ks0.5 where: V = Velocity in fps

k = Intercept coefficient

(see Table 1101-1)

s = Overland slope (percent)

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Drainage Design Procedures

Table 1101-1 Types of Surface

Intercept Coefficient “k”

Forest with heavy ground litter 0.076

Min. tillage cultivated; woodland 0.152

Short grass pasture 0.213

Cultivated straight row 0.274

Poor grass; untilled 0.305

Grassed waterways 0.457

Unpaved area; bare soil 0.491

Paved area 0.619

Shallow concentrated flow generally empties into pipe systems, drainage ditches, or natural channels. The velocity of flow in an open channel or pipe can be estimated using the Manning's equation. The travel time for both shallow concentrated flow and open channel or pipe flow is calculated as follows:

60VLtort ds =

where: ts = Travel time for shallow concentrated

flow in minutes

td = Travel time for open channel or pipe flow in minutes

L = Flow length in feet

V = Velocity in fps

Where a contributing drainage area has its steepest slope and/or highest "C" value in the sub-area nearest the point of concentration, the rational method discharge for this sub-area may be greater than if the entire contributing drainage area is considered. The maximum runoff rate for a sub-area should be considered only if greater than that for the entire area. 1101.2.3 Coefficient of Runoff

The coefficient of runoff is a dimensionless decimal value that estimates the percentage of rainfall that becomes runoff. The recommended values for the coefficient of runoff for various contributing surfaces are shown in Table 1101-2. Where two values are shown, the higher value ordinarily applies to the steeper slopes. For Residential areas, lot size should also be considered in choosing the appropriate value for the coefficient of runoff. Generally, a higher value should be associated with smaller lots and a lower value should be associated with larger lot sizes. The selected coefficient should be based upon an estimation of the typical slope, lot size, and lot development. The total width contributing flow to a given point usually consists of surfaces having a variable land cover and thereby requires a weighted coefficient of runoff “C”. The weighted coefficient is obtained by averaging the coefficients for the different types of contributing surfaces, as noted in the following example:

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Table 1101-2

Types of Surface

Coefficient of Runoff “C”

Pavement & paved shoulders 0.9

Berms and slopes 4:1 or flatter 0.5

Berms and slopes steeper than 4:1 0.7

Contributing areas

Residential (single family) 0.3-0.5

Residential (multi-family) 0.4-0.7

Woods 0.3

Cultivated 0.3-0.6

Contributing Width “W”

Land Use “C” “CW”

20 feet Paved Area 0.9 18 40 feet Earth Berms &

Slopes 0.7 28

140 feet Residential Area 0.6 84 200 feet Summations 130 Weighted “C” = 130/200 = 0.65

1101.2.4 Rainfall Intensity

The average rainfall intensity “i” in inches per hour may be obtained from the Intensity-Duration-Frequency curves shown on Figure 1101-2. Each set of curves applies to a specific geographic area, A, B, C, or D as shown on the Rainfall Intensity Zone Map, Figure 1101-3. The geographic areas were established from an analysis of rainfall records obtained from Weather Bureau stations in Ohio. Some political subdivisions may have developed curves for their specific area similar to Figure 1101-2. Such curves may be based on a much longer period of record and provide more reliable information. Any local curves proposed by the designer should be cleared with the Office of Hydraulic Engineering (OHE) prior to incorporating that information in the drainage calculations.

1102 Open Water Carriers

1102.1 General

Open water carriers generally provide the most economical means for collecting and conveying surface water contributing to the roadway. The required capacity of a water carrier involves a determination of the velocity and depth of flow for a given discharge. These characteristics can best be obtained from charts that are based on Manning’s equation. Channel flow charts have been prepared for all the common water carrier shapes and are included in the Drainage Design Aids. A ditch computation sheet similar to that provided in the Appendix shall be used to perform or summarize ditch calculations. As a guideline, the relative minimum roadway ditch grades should be 0.50% with a recommended absolute minimum of 0.25%. Lower grades may be used on large channels as necessary. Open water carriers should maintain a constant slope wherever possible. The proper location of a ditch outfall is quite important. Existing drainage patterns should be perpetuated insofar as practicable. Care should be taken to not capture an existing stream with the roadside ditch. If this is necessary, the designed ditch shall be in accordance to Section 1102.2.4. 11-4 January 2015

Drainage Design Procedures 1102.2 Types of Carriers

1102.2.1 Standard Roadway (Roadside) Ditches

The various roadside ditches shown in Volume I, Roadway Design, have proven to be safe and to provide adequate flow capacity. A ditch is considered to be standard when the centerline is parallel to the edge of the pavement and the flowline is a uniform distance below the edge of pavement. A modification of the above is required when the grade of the pavement is too flat to provide acceptable ditch flow, thereby creating the need for a special ditch. Channel charts, Drainage Design Aid Figures 1100-1 through 1100-10, are included for use in determining velocity and depth of flow for standard ditches having variable side slopes. 1102.2.2 Special Ditches

Special ditches other than the modified standard roadway ditch described in Section 1102.2.1 above, include the following: A. The steep ditch beyond the toe of the embankment used to carry the flow from a cut section to the

valley floor. B. Toe of fill ditch which is separated from the toe of fill by a minimum 10 foot wide bench, having a

minimum transverse slope of ½ inch per foot toward the ditch. C. Deep parallel side ditches separated from the pavement by a wide bench or earth barrier. The special ditches described in A, B and C above are ordinarily trapezoidal in shape and appropriate charts for the hydraulic analysis are included in this section of the manual or in the FHWA publication “Design Charts for Open Channel Flow”’ Hydraulic Design Series No. 3. It is required that the calculated flowline elevation be shown on each special ditch cross section. 1102.2.3 Median Ditches

The median ditches that are an integral part of all earth medians have the same shape and capacity features as the standard roadside radius ditch and the appropriate ditch chart is applicable for the hydraulic analysis. The fully depressed earth median provides adequate hydraulic capacity and the appropriate flow charts in the Drainage Design Aid Figures 1100-11, 1100-12 and 1100-13 have been developed for that shape. The rounding shown on the charts varies from 8 feet to 4 feet, depending on the width of the median. The slight discrepancy in the rounding from that shown in Volume I, Roadway Design, is not considered to affect the accuracy of the charts. 1102.2.4 Channel Relocations

Major channel relocations should be avoided. However, if it becomes necessary to relocate a channel adhere to the following: The design year frequency used for channel relocations shall be that given in Section 1004.2. All channel relocations shall carefully be designed to preclude erosion or unreasonable changes in the environment. Whenever possible, channel relocations shall be restricted to the downstream end of proposed culverts. The relocated channel shall be of a similar cross-section. Where the existing channel exhibits a two-stage cross section morphology, it shall be replaced with like kind. The two-stage channel is comprised of two distinct areas. The first of these is a meandering bankfull width that carries the channel-forming discharge. The second area is the flood plain width. See Figure 1102-2 for a graphical representation of the major channel features.

January 2015 11-5

Drainage Design Procedures The proposed channel should be designed such that it matches the existing channel as closely as possible in regards to existing geomorphic conditions (e.g., channel slope and length, velocity, depth of flow, cross-sectional geometry, channel sinuosity, energy dissipation, etc.). The existing channel geometry and physical characteristics should be established from reference reaches and idealized geometry. The reference reaches should be selected from stable channel reaches close to the relocated section or in locations with similar watershed and valley conditions. The relocated channel should be designed to duplicate the existing hydraulic properties for the bankfull design frequency. The flood clearance criteria given in Section 1005 should also be met. Additional information on the design of relocated channels can be found in the United States Department of Agriculture publication, “Stream Corridor Restoration: Principles, Practices and Processes”. The principals given in this publication utilize idealized channel geometry. The actual design should be refined using the channel geometry and physical characteristics of reference reaches. 1102.2.5 Channel Linings and Bank Stabilization

The use of soil bioengineering should be used to stabilize banks for relocated or impacted channels when practicable. Native plant species should be used when feasible. Bank stabilization using bioengineering is covered in the previously referenced USDA publication as well as the AASHTO Model Drainage Manual and the USDA Engineering Field Handbook, chapter 16, part 650. The design procedures and methods for determining the effectiveness of the traditional channel linings are covered in the Federal Highway Administration Hydraulic Engineering Circular No. 15 “Design of Stable Channels With Flexible Linings”. 1102.3 Ditch Design Criteria - Design Traffic Exceeding 2000 ADT

1102.3.1 Design Frequency

Determine the depth of flow using a 10-year frequency storm, and determine the shear stress and width of the ditch lining (if required) using a 5-year frequency storm. Where a flexible ditch lining is required for calculated stresses exceeding the allowable for seed, the minimum width of the lining shall be 7.5 feet. Additional required width is in increments of 3.5 feet. The installed width of all ditch linings is centered on the flow line of the ditch. The depth of flow shall be limited to an elevation 1 foot below the edge of pavement for the design discharge. The depth of flow in toe of slope ditches shall be further limited such that the design year discharge does not overtop the ditch bank. 1102.3.2 Ditch Protection

The shear stress for the five-year frequency storm shall not exceed the values shown in Table 1102-1 for the various flexible linings.

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Table 1102-1

Allowable Shear Stress Permanent Protection

Protective Lining Allowable Shear

Stress (psf)

Seed (659) 0.40

Sodding, Ditch Protection (660)

1.0

Temporary Protection

Ditch Erosion Protection Mat Type___ (670)

A 1.25

B 1.50

C 2.0

E 2.25 F 0.45

G 1.75

The temporary linings will reach a value of 1.0 psf upon vegetation establishment. Use the temporary lining shear stress values in Table 1102-1 on a temporary basis only (6 months or less). Calculate the actual shear stress by the following equation:

D= Water surface depth ft

S = Channel slope ft/ft

τac = Actual shear stress lbs/ft2

If the calculated shear stress exceeds that shown in table 1102-1 then use the following permanent shear stress values within the stated limitations: A. Seeding and Erosion Control with Turf Reinforcing Mat (Supplemental Specification 836) where the

ditch slope is less than 10% and maximum shear stress are as follows:

Turf Reinforcing Mat Type

Maximum Shear Stress (psf)

Type 1 2.00 Type 2 3.00 Type 3 5.00

B. Type B, C or D Rock Channel Protection may be used to line the ditch if the nearest point of the lining

is outside the design clear zone or located behind guardrail or barrier. The actual shear stress is based upon the parameters of the channel slope and depth of flow for the 5-year discharge. The shear equation is valid for discharges less than 50 cfs with slopes less than 10% when evaluating Rock Channel Protection.

τ ac= 62.4 D. S.

January 2015 11-7


Allowable Shear Stress RCP Type τa lbs/ft2

B 6 C 4 D 2

C. Type B or C RCP may be utilized for lining ditches on steep grades (slopes from 10%- 25%) that

carry flow from the end of a cut section down to the valley floor. Use HEC-15 procedures with a safety factor of 1.5 for steep gradient channels (refer to HEC-15). Contact OHE for further guidance of RCP usage for 5-year discharges greater than or equal to 50 cfs.

D. Tied concrete block mat protection (601) may be used for slopes and swales with 2:1 or flatter side

slopes with profile grades at 25% or less. The matting may be used within the clear zone provided that the top of the blocks are flush with the finished grade. Install per the manufacturers recommendations. The allowable shear stress for each type is shown in table 1102-2.

Table 1102-2

Tied Concrete Block Mat Shear Stress

E. Articulating concrete block revetment system (601) may be used for slopes and channels with 2:1 or

flatter side slopes. The revetment may be used within the clear zone provided that the top of the blocks are flush with the finished grade. Install per the manufacturers recommendations. The allowable shear stress for each type is shown in table 1102-3.

Table 1102-3

Articulating Concrete Block Revetment System Shear Stress F. A concrete lining should be considered only as a last resort. Contact OHE, before using a concrete

lining. 1102.3.3 Roughness

Suggested values for Manning’s Roughness Coefficient “n” for the various types of open water carriers are listed in Table 1102-3.

Type Allowable Shear Stress (lbf/ft2) 1 3 2 5 3 7

Type Allowable Shear Stress (lbf/ft2) 1 17 2 20 3 23

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Table 1102-3

Type of Lining Roughness Coefficient

Bare Earth . . . . . . . . . . . . . . . . . 0.02 Seeded . . . . . . . . . . . . . . . . . 0.03 Sod . . . . . . . . . . . . . . . . . . . . 0.04 Item 670 . . . . . . . . . . . . . . . . . 0.04 Erosion Control Matting . . . . . . . 0.04 Concrete . . . . . . . . . . . . . . . . . 0.015 Bituminous . . . . . . . . . . . . . . . . . 0.015 Grouted Riprap . . . . . . . . . . . . . 0.02 Tied Concrete Block Mat . . . . . . 0.03 Rock Channel Protection . . . . . . . . . . .

0.06 for ditches 0.04 for large channels

1102.3.4 Catch Basin Types

The Standard No. 4, 5, and 8 Catch Basins are suitable for the standard roadside designs covered in Volume I, Roadway Design. The tilt built into the basin top provides a self-cleaning feature when the basins are used on continuous grades and the wide bar spacing minimizes clogging possibilities, thereby resulting in an efficient design. The bases of the 4, 5 and 8 Catch Basins can be expanded to accommodate larger diameter conduits by specifying Standard Construction Drawing CB-3.4. The bar spacing can be decreased, when desirable for safety reasons, by specifying Grate “E” for the No. 4 and Grate “B” for the No. 5. Provide 150 feet of ditch erosion protection upstream of all No. 4, 5 and 8 Catch Basins, regardless of velocity. The following catch basin types are generally recommended based on the size and shape of the ditch. A. Standard No. 4 for depressed medians wider than 40 feet. B. Standard No. 5 for 40 foot radius roadside or median ditches. (Use Grate “B” where pedestrian traffic

may be expected.) C. Standard No. 8 for 20 foot radius roadside or depressed medians 40 feet or less in width. D. Standard No. 2-2-A may be used in trapezoidal toe ditches where the basin is located in a rural area.

The basin should also be located outside the design clear zone or behind guardrail where the protruding feature of the basin is not objectionable. The capacity of the side inlet catch basin window, for unsubmerged conditions, may be determined by the standard weir equation:

Q=CLH3/2

where C is a weir coefficient, generally 3.0, L is the length of opening in feet, H is the distance from the bottom of the window to the surface of the design flow in feet. The catch basin grate is considered as an access point for the storm sewer and its capacity to admit flow is ignored for continuous grades.

E. Standard No. 2-2-B should be used where minor, non-clogging flows are involved such as yard

sections and the small triangular area created by the guardrail treatment for a depressed median at bridge terminals. Standard No. 2-3 through No. 2-6 catch basins should be provided where a larger base is required to accommodate pipes larger than 21 inches in span or sewer junctions, or where a No. 2-2-B catch basin will not provide adequate access to the sewer.

F. In urban areas, Standard Side Ditch Inlets should be used to drain small areas of trapped water

behind curbs and/or between driveways. 1102.3.5 Calculated Catch Basin Spacing

Catch basins must be provided to intercept flow from open water carriers when the depth of flow or velocity exceeds the maximum allowable for

January 2015 11-9

Drainage Design Procedures the design storm for all highway classifications. The standard ditch catch basins, designated Catch Basin No. 4, Catch Basin No. 5, and Catch Basin No. 8, include an earth dike. The dike is approximately 12 inches above the flowline of the grate, immediately downstream from the catch basin and serves to block the flow on continuous grades and create a sump condition. When the calculated depth of flow or velocity exceeds the maximum allowable at the checkpoint in the ditch, a catch basin or ditch lining will be required. However, the capacity of the catch basin may be less than the capacity of the ditch and thereby control the catch basin spacing. Figure 1102-1 may be used to check the capacity of a catch basin grate in a sump. To use Figure 1102-1, the calculated discharge at the ditch checkpoint shall be doubled to compensate for possible partial clogging of the grate. In cut sections, the accumulated ditch flow shall be carried as far as the capacity, allowable depth, or velocity of flow will permit. The first catch basin in the roadside or median ditch will determine the need for a storm sewer system required for the remainder of the cut. Velocity control should be extended as far as inexpensive flexible ditch linings will permit. Consideration should also be given to providing positive outlets for underdrains and providing access to longitudinal sewer systems when locating ditch catch basins. 1102.3.6 Arbitrary Maximum Catch Basin Spacing

Catch basins are required at the low point of all sags and the earth dike noted in Section 1102.3.5 shall be omitted. The maximum distance between catch basins in depressed medians in fill sections shall be as shown in Table 1102-4. Where underdrains are utilized, catch basins shall be provided at a maximum spacing of 1000 feet (500 feet with free draining base) to provide a positive outlet for underdrains.

Table 1102-4 Depressed Median Catch Basin Spacing

(Fill Sections) Median Width

Desirable Spacing

Maximum Spacing

84 feet 1250 feet 1500 feet



1102.4 Ditch Design Criteria - Design Traffic of 2000 ADT or Less


A 5-year frequency storm shall be used to determine the depth of flow, and a 2-year frequency to determine the shear stress of flow and width of ditch lining, where needed. The depth of flow shall be limited to an elevation 9 inches below the edge of pavement for the design discharge. The depth of flow in toe of slope ditches shall be further limited such that the design year discharge does not overtop the ditch bank. The minimum width of lining shall be in accordance with Section 1102.3.1. 1102.4.2 Shear Stress Protection

Shear stress protection shall be in accordance with 1102.3.2 except that a 2-year frequency event shall be used. 1102.4.3 Roughness

The roughness used for the hydraulic analysis shall be based on the Manning's Roughness Coefficient values shown in Table 1102-3.

11-10 January 2015

Drainage Design Procedures 1102.4.4 Catch Basin Types

Standard No. 5 Catch Basins, No. 2-2-A Catch Basin (within their safety limitations as discussed in Section 1102.3.4(D)) and No. 2-2-B Catch Basins should be considered for the lower ADT highways. Standard No. 4 Catch Basins should be used where additional capacity is required. 1102.5 Design Aids for Ditch Flow Analysis

1102.5.1 Earth Channel Charts

Standard radius roadside ditch charts have been prepared, based on the Manning’s equation, to facilitate the hydraulic analysis of ditch flow and are included in the Drainage Design Aids. Some of the more commonly used trapezoidal channel charts are also included. Other trapezoidal channel charts (with 2:1 - 2:1 side slopes and bottom widths varying from 2 feet to 20 feet are available in the Federal Highway Administration publication referenced in section 1102.2.2. All earth channel charts have been prepared using a Manning's Coefficient of Roughness of 0.03, which is recommended for a seed lining (Construction and Material Specifications Item 659). Qn and Vn scales have been included on all channel charts so that the channel flow may be analyzed for any value of “n” depending on the roughness of the channel or lining. 1102.5.2 Rectangular Channel Charts

Vertical side channel charts that can be used to analyze the open channel flow in box culverts are included in the Federal Highway Administration publication “Design Charts for Open Channel flow,” previously referred to.

1103 Pavement Drainage

1103.1 General

When curbs are provided at the edge of pavement or paved shoulder, (primarily in urban areas), it is necessary to determine the proper type of pavement inlet (or catch basin) to control the spread of water and depth of flow on the pavement. Present day geometric design has resulted in relatively flat transverse and longitudinal pavement slopes. These slopes require more pavement inlets (or catch basins) and consequently result in an appreciable increase in the drainage cost. To alleviate the above, where curb is permissible, standard curb and gutter should be used adjacent to the pavement. On normal section multi-lane highways where three (3) or more lanes are sloped in the same direction, it is desirable to counter the resulting increase in flow depth by increasing the cross slope of the outermost lanes. The two (2) lanes adjacent to the crown line should be pitched at the normal slope of 1.6 percent, and successive lane pairs or portions thereof outward, should be increased by 0.4 percent. Refer to Location and Design - Volume 1, Roadway design for additional geometric design criteria. If paved shoulders are provided, the drainage cost will be decreased appreciably due to the large volume of flow that can be carried on the pavement shoulder without exceeding the allowable depth of 1 inch below the top of curb or a maximum of 5 inches; a maximum depth of 6 inches is permissible where a barrier shape is provided adjacent to the pavement. Furnish a drainage design that will reduce the need for bridge scuppers by intercepting the flow prior to the bridge. A pavement drainage computation sheet similar to that provided in the Appendix shall be used to perform or summarize necessary computations. Additional information concerning pavement drainage can be obtained from the Federal Highway Administration Hydraulic Engineering Circular No. 22, "Urban Drainage Design Manual." January 2015 11-11

Drainage Design Procedures 1103.2 Design Frequency

Pavement inlets (or catch basins) shall be spaced to limit the spread of flow on the traveled lane (considered to be 12 feet wide) as shown in Table 1103-1. The allowable spread may be increased slightly for streets carrying predominantly local traffic and with design speeds less than 45 mph. Design shall be based upon the following frequencies:

Freeways . . . . . . . . . . . . . . . . . . . . . . . 10 Years High volume highways (over 6000 ADT Rural or 9000 ADT Urban) . . .

5 Years

All other highways . . . . . . . . . . . . . . . . 2 Years

For underpasses or other depressed roadways where ponded water can be removed only through the storm sewer system, the spread shall be checked for a 50-year storm for Freeways and high volume highways as defined above, and for a 25-year storm for other multiple lane highways. Typically, this criteria does not apply to 2-lane facilities. Contact OHE if encountered. The ponding will be permitted to cover all but one through lane of a multiple lane pavement. The depth of flow at the curb shall not exceed 1 inch below the top of the curb for the design discharge regardless of the type of highway. A maximum depth of 6 inches is permissible where a barrier shape is provided adjacent to the pavement.

Table 1103-1 Allowable Pavement Spread*

Freeways 0 feet

High Volume Highways (Over 6000 ADT rural or 9000 ADT urban)

≥ 45 mph 4 feet

< 45mph 2 lanes 6 feet

≥4 lanes 8 feet

All other Highways 2 lanes 6 feet

≥4 lanes 8 feet

*Pavement spread applies to the through lane only 1103.3 Estimating Design Discharge

Runoff contributing to curbed pavements shall be estimated by the rational method, as explained in Sections 1101.2.2, 1101.2.3 and 1101.2.4. The time of concentration “tc” shall be the actual time of concentration calculated according to Section 1101.2.2 with an absolute minimum time of 10 minutes. In urban areas, where justifiable (e.g. contributing drainage area would be difficult to determine), the “strip method” may be used to determine contributing drainage areas. The strip method assumes a contributing drainage area of 150 feet taken on each side of the roadway centerline. 1103.4 Capacity of Pavement Gutters

A pavement gutter has a right triangular shape, with the curb forming the vertical leg and the straight pavement slope, the gutter plate of a curb and gutter, or a paved shoulder forming the hypotenuse. A standard curb and gutter adjacent to a straight pavement slope, or paved shoulder, forms a composite gutter section which complicates the flow analysis. In most cases, the top width of the water surface in a pavement gutter far exceeds the height of the curb. The hydraulic radius does not accurately describe the gutter cross section in this situation, thereby requiring a modification to the Manning’s equation to analyze the gutter flow. The accepted modification results in the following equation:

11-12 January 2015


𝑄𝑄 = 0.56𝑍𝑍𝑆𝑆1/2𝑑𝑑8/3

𝑛𝑛

where: Q = Discharge in cubic feet per second Z = Reciprocal of the pavement cross

slope n = Manning’s Coefficient of Roughness

(Table 1102-3)

s = Longitudinal pavement slope

d = Depth of flow in gutter section at curb in feet

Figure 1103-1 provides a graphical solution for the above equation and its use is comparatively simple for straight transverse pavement slopes. However, the use of the Nomograph to determine depth of flow at the curb and resulting spread on the pavement for composite sections is much more involved. 1103.5 Pavement Flow Charts

Charts have been prepared for the more commonly used curbed pavement typical sections, and they are included in the Drainage Design Aids. The charts are particularly helpful for determining the flow for composite pavement sections where the spread can be read directly from the appropriate Pavement Flow Chart. To use the charts, enter with a predetermined design discharge (total flow) Qt in the gutter in cubic feet per second and proceed vertically to intersect the longitudinal gutter slope line. At that intersection, read the spread in feet shown on the diagonal spread lines. The spread of flow will generally control the pavement inlet or catch basin spacing, where the transverse and longitudinal slope of the pavement is relatively flat. The above is prevalent in long flat sag vertical curves, where a flanking inlet (or catch basin) should arbitrarily be provided on both sides of the low point in a pavement sag. This is particularly so for Freeways. Three inlets or catch basins in a sag can be justified only on the basis of need for other highway classifications. Usually a Standard 6 foot pavement inlet or No. 3A catch basin will be adequate, and they should be placed where the grade elevation is approximately 0.20 feet higher than at the low point. Furnish a CB-No. 3 at the sump. Inlets or catch basins should arbitrarily be placed upstream of all intersections, bridges and pedestrian ramps. When justified, inlets (or catch basins) should be located a minimum of 10 feet off drive aprons, intersection return radii, pedestrian ramps or curb termini. 1103.6 Bypass Charts for Continuous Pavement Grades

Bypass charts are included for the standard pavement inlets and catch basins in the Drainage Design Aids. Bypass for a given structure can be read directly from the chart (At the intersection of the spread, determined in Section 1103.5, and the longitudinal gutter slope, read the bypass flow Qb on the abscissa). Experience has proven that, for greater efficiency, inlets should be sized to bypass a minimum of 10% to 15% of the design discharge. This criterion should be used to determine the type or length of inlet to be used in a given location. It is not intended to establish the required spacing. The most efficient design maintains the allowable spread on continuous grades and at the sag. The bypass for a catch basin or inlet should be added to the total flow in the adjacent downstream gutter section.

January 2015 11-13

Drainage Design Procedures 1103.6.1 Curb Opening Inlets

The flow bypassing a standard curb opening inlet, for pavement transverse slopes or combination of slopes differing from the charts included in the Drainage Design Aids, may be obtained from Figure 1103-2. The use of curb opening inlets should be avoided where bicycle traffic is expected. 1103.6.2 Grate or Combination Grate and Curb Opening Inlet

The standard pavement catch basin in this category is considered to intercept all the flow over the grate when used on continuous grades. A portion of the flow outside of the edge of the grate will also be intercepted, the amount varying with the depth of flow “y” along the edge of the grate. The depth “y” can be determined from Figure 1103-1, and the resulting flow spilling over the edge of the grate from Figure 1103-2, using a ½ inch local depression for straight transverse pavement slopes, or no local depression for a composite gutter section. The local depression mentioned above is at the front face of the grate closest to the centerline of the roadway. This depression is not the same depression identified in the in the standard construction drawings. The curb opening of a combination catch basin on a continuous grade will admit some flow, particularly if there is a partial clogging of the grate; however, the additional capacity should be considered as a factor of safety only. 1103.7 Grate Catch Basins and Curb Opening Inlets in Pavement Sags

The spread determined from the pavement flow charts need not be checked any closer than 25 to 50 feet on either side of the sag, well beyond the limits of the local depression. The spread in the sag should be determined from the depth of flow at the edge of grate using Figure 1103-3 and should include the total flow (contributions from each side of the sag vertical curve) reaching the inlet or catch basin. Standard No. 3 catch basins should be used in pavement sags. The capacity of the grates to admit flow is based on the depth of ponding around the grates. The capacity of the grates shown in Figure 1103-3 is based on weir flow over the edge of the grate, up to a depth of 0.4 feet. For greater depths, the total area of grate opening is considered, with no deduction made for possible clogging. When evaluating the spread in a depressed sag for a 25-year or 50-year event, the capacity of the window shall be considered. This capacity may be obtained from Figure 1103-4. The curb opening capacity should be added to the grate capacity for submerged conditions.

Where the low point of a sag vertical curve occurs in a drive, a No. 6 catch basin should be provided at the low point with flanking No. 3A catch basins as per Section 1103.5.

No. 6 catch basins may be used along curbed roadways and medians provided that the grate capacity is not exceeded.

1103.8 Bridge Deck Drainage

Furnish a minimum longitudinal grade of 0.3% for the bridge deck surface when using concrete parapets.

Minimize or eliminate the number of scuppers. Calculate the allowable spread of flow using procedures described in Section 1103. Locate scuppers inside the fascia beam unless the parapet and beam spacing make this impractical. Furnish scuppers with vertical drops or nearly vertical drops when feasible. If a scupper pan is required, angle the pan as steeply as possible. Furnish an uncollected / free fall as per SCD GSD-1-96. Substitute heavy duty cast iron deck drains as currently manufactured by Neenah or equal, when SCD GSD-1-96 will not physically fit due to parapet, beam line and the deck overhang. If a drainage collection system is required ensure that it meets the following: A. System is sloped greater than or equal to 15 degrees

B. Bends have a minimum radius of 18 inches

11-14 January 2015

Drainage Design Procedures C. Bends have angles greater than 90 degrees

D. Cleanout plugs are easily and safely accessible

E. F1008-1urnish drainage collection when using finger joints or sliding plates. Provide a neoprene

drainage trough under finger joints. Show the necessary deck drainage outlet locations on the preliminary structure site plan. Include this information in the Structure Type Study (BDM 201).

Place scuppers with drainage collection systems as close as feasible to the substructure unit which drains them. Place uncollected / free fall scupper downspouts as far away from any part of the structure as possible. See Section 1113 for bridge bypass flow. 1103.9 Slotted Drains and Trench Drains

Slotted and Trench drains are used to capture sheet flow in areas where curb is not present to collect and direct flow to a catch basin such as a gore area. Trench drains and slotted drain systems are susceptible to clogging and are not recommended where significant sediment or debris load is present. Locate trench drains and slotted drains longitudinally with the edge of pavement. Ensure the drain and any surrounding concrete is outside of the travelled way. Locate trench drains at the end of commercial drives to intercept large flows before entering into the travelled way. Outlet the drains to a Catch Basin No.6 to aid in cleanout. Furnish a Catch Basin No. 6 at minimum 100 ft. intervals to facilitate cleanout for slotted drains. Refer to SCD DM-1.3 for slotted drain details. Furnish Plan Note D120 when utilizing slotted drain. Specify supplemental specification 839 and 939 when using trench drain.

1104 Storm Sewers

1104.1 General

Storm sewer systems are designed to collect and carry storm water runoff from the first pavement or ditch inlet, or catch basin to the predetermined outlet. (Further reference to inlets infers either inlets or catch basins). Long cut sections often result in the need for longitudinal trunk sewers to accept the flow from a series of inlets. The proper location of a sewer outlet is important. Existing drainage patterns should be perpetuated insofar as practicable. Careful consideration should be given to the possibility of actionable damage for the diversion of substantial volumes of flow. Long fill sections requiring median or pavement drains may best be served by transverse sewers that outlet independently at the toe of fill ditch. Storm sewer systems shall be sized to convey the current flow from areas naturally contributing to the highway or from intercepting existing storm sewers. Adherence to Local drainage criteria and standards is not applicable for ODOT owned and maintained drainage assets. Storm sewer systems may be oversized at the request of a local government entity to convey flow from areas beyond those considered highway responsibility or increased flows from anticipated development with the approval of the OHE. The additional cost to construct the increased sized storm sewer system will be the responsibility of the local government. The proration of project funds and local government funds will be determined from estimated construction costs. The project funding participation will be determined as a percentage of the total cost of the affected plan items. The percentage will be computed by dividing the estimated cost to

January 2015 11-15

Drainage Design Procedures construct a highway responsibility system only by the estimated cost to construct the oversized system. The affected plan items and participation percentage will be noted in the plan general summary. Type B conduit shall be specified for storm sewers under pavement, paved shoulders and commercial or industrial drives and Type C conduits for storm sewers beyond those limits. However, the type of conduit shall not be changed for a short run of conduit which would ordinarily require a change in conduit type. As an example of the above, Type B should be used for a transverse conduit that is required to drain an earth median catch basin in an embankment section under the pavement to a point approximately 10 feet from the embankment slope. A concrete collar, as per Standard Construction Drawing DM-1.1, should be provided to connect the Type B and a Type F Conduit, located back of, and parallel to, the embankment slope. Type F conduit, 707.05 Type C or 707.21 shall be provided for the pipe specials required to negotiate the bend at the top and bottom of the embankment. A detail is provided in Figure 1104-1. The Construction and Material Specifications stipulate the permissible pipe shapes and materials. Storm sewer designs will be based on round pipe, and the choice of the permissible material types for the conduit specified will be the contractor’s option. When extending existing Type B & C conduits, the extensions will match the existing material in kind. The length of conduit to be paid for will be the actual number of linear feet, measured from center-to-center of appurtenant small structures. No deduction will be made for catch basins, inlets or manholes that are 6 feet or less across, measured in the direction of flow. Conduits placed on slopes steeper than 3:1 or with beveled or skewed ends are measured along the invert. Changes to grade may occur at existing manholes due to proposed work. With a decrease in grade of not more than 6 inches or an increase in grade of not more than 12 inches the existing structure may be Adjusted to Grade. Where grade elevation changes are greater, the existing structure should be Reconstructed to Grade. 1104.2 Design Considerations

1104.2.1 Storm Sewer Depth

Keep a storm sewer system as shallow as possible, consistent with the following controls: A. Provide a minimum cover of 9 inches from the top of a rigid pipe to the bottom of the pavement

subbase; however, in no installation shall the distance from the top of the rigid pipe to the pavement surface be less than 15 inches. Provide a minimum cover of at least 18 inches for pipe not under pavement.

B. Provide a minimum cover of 12” from the top of flexible pipe to the bottom of the pavement subbase;

however, in no installation shall the distance from the top of the flexible pipe to the pavement or ground surface be less than 24”.

C. Provide a minimum cover of 4” from the top of extra strength pipe to the bottom of the pavement

subbase; however, in no installation shall the distance from the top of the extra strength pipe to the pavement surface be less than 10 inches. Provide a minimum cover of at least 4” if not under the pavement. Check with OHE to determine the required extra strength. If 10 inches of minimum cover is not achievable, the pipe is required to be special designed and shown as per plan.

D. Provide a sufficient depth to permit the use of precast inlets, catch basins and manholes. Refer to the

Standard Construction Drawings for this information. In no installation shall the top of pipe be in the precast top section of the inlet, catch basin or manhole. See Table 1104-1 for maximum storm sewer pipe thicknesses.

E. Provide a sufficient depth to avoid interference with existing utilities such as sanitary sewers, the

grade of which cannot be changed. F. Provide a sufficient depth to create a positive outlet for underdrains. It is desirable to maintain the

underdrain outlet 12 inches above the flow line of the outlet structure with 6 inches as a minimum.

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Drainage Design Procedures G. Provide sufficient slope to maintain a minimum velocity of 3 feet per second, for self-cleansing. This

velocity is calculated using the “just full” Manning’s Equation. H. Match the crown of a smaller upstream pipe in a longitudinal trunk sewer to the crown of the adjacent

downstream pipe. I. Minimum invert elevation = finished grade – minimum cover – wall thickness (per Table 1104-1) –

inside diameter

Table 1104-1 Dimensions of Wall Thickness for Storm Sewer

Inside Diameter

(inch) Wall Thickness

(inch)

Outside Diameter

(inch) 12 2 16 15 2-1/4 19-1/2 18 2-1/2 23 21 2-3/4 26-1/2 24 3 30 27 3-1/4 33-1/2 30 3-1/2 37 36 4 44 42 4-1/2 51 48 5 58 54 5-1/2 65 60 6 72 66 6-1/2 79 72 7 86

Where proposed highway storm sewers or ditches will interfere with existing private drains carrying treated or untreated sanitary flow, submit the names and addresses of the affected property owners to the District Deputy Director. Obtain the above information well in advance of the Field Drainage Review so the appropriate provisions of Directive No. 22-A can be followed (found in the Appendix A). 1104.2.2 Storm Sewer Access

Most standard catch basins and pavement inlets will provide sufficient access to small shallow sewers. Catch basin or pavement inlets can be used to negotiate changes in sewer sizes or minor horizontal or vertical direction changes within the size limitation of the structure, but more pronounced changes may require manholes. It may be necessary, or desirable to locate longitudinal trunk sewers away from the curb to provide for a utility strip between the curb and the sidewalk and to avoid a conflict with the underdrain system. This will require properly spaced manholes in the sewer line. Small sewers (under 36 inches in diameter) located under or near the edge of pavement, should be accessible at intervals not to exceed 300 feet. For sewers sized 36 to 60 inches manholes should be spaced every 500 feet maximum. Manholes should be provided every 750 to 1000 feet maximum for larger sewers. 1104.2.3 Rock Excavation for Storm Sewer

If it is known that bedrock will be encountered in the excavation for storm sewer installation, relocate the storm sewer. If bedrock cannot be avoided, separate the quantities of the storm sewer in rock and include “611, As Per Plan” in the plans.

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Drainage Design Procedures 1104.3 Layout Procedure

1104.3.1 Plan

A print of the plan sheets involved should be used to spot catch basins and inlets that are required to drain the project and satisfy maximum allowable depth and/or spread of flow. A strip map showing the delineated drainage area and topography is required. The map will provide the designer with a means of determining the drainage area and the weighted coefficient of runoff for the individual areas contributing flow to the required storm sewer system. 1104.3.2 Profile

A profile of the existing and proposed pavement or ground line over the proposed sewer location should be plotted. On the same profile, plot the locations of catch basins, inlets and manholes, along with a tentative storm sewer system. 1104.4 Storm Sewer Design Criteria


All storm sewers shall be sized to flow just full (i.e. depth of flow for maximum discharge) for a 10-year frequency storm. The size is determined by working downstream from the first sewer run. It will be acceptable to use a discharge of a more frequent occurrence if consistent with local criteria (depending upon the design ADT of the roadway) or to avoid extensive replacement of an existing downstream drainage system. 1104.4.2 Hydraulic Grade Line

Starting at the storm sewer system outlet and working upstream, the elevation of the hydraulic grade line at the upper end of each sewer run should be determined using a 25-year frequency. It will be acceptable to use a discharge of a more frequent occurrence if consistent with local critera (depending upon the design ADT of the roadway) or to avoid extensive replacement of an existing downstream drainage system. Ordinarily, the hydraulic grade line will be above the top of the pipe, causing the system to operate under pressure. If, however, any run in the system does not flow full, (pipe slope steeper than the friction slope) the hydraulic grade line will follow the friction slope until it reaches the normal depth of flow in the steep run. From that point, the hydraulic grade line will coincide with the normal depth of flow until it reaches a run flatter than the friction slope for that run. The starting elevation for the hydraulic grade line determination should be the higher of either: the downstream tail water channel water surface elevation or (dc+D)/2 at the system outlet. Section 1105.6.1 The intensity “i” in the rational equation Q=CiA [Q=CiA/360] used to determine the check discharge (25-year frequency) shall be the same for all sewer runs as that calculated for the last, or downstream run, in a continuous sewer system. The hydraulic grade line shall not exceed the following for any roadway with greater than 2000 ADT: A. 12 inches below the edge of pavement for sections without curb. B. The elevation of a curb opening inlet or grate elevation of a pavement catch basin. Consideration shall be given to a reduction in the design frequency and to more liberal hydraulic grade line controls for less important highways than those noted above. The check discharge, to determine the elevation of the hydraulic grade line for highways having depressed sags that must be drained by storm sewers, shall be based on a 50-year frequency. One directional lane of a multiple lane highway or one-half of a lane on a 2-lane highway should be passable when the sewer system is discharging the 50-year storm.

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Drainage Design Procedures Storm sewers for all highways shall satisfy a 50-year check to preclude flooding of buildings or extensive flooding of private property. If the hydraulic grade line exceeds the limits noted above, the controlling sewer size shall be increased. (These criteria are not intended to lower existing high water elevations) 1104.4.3 Coefficient of Runoff

The weighted coefficient of runoff shall be determined as explained in Section 1101.2.3 1104.4.4 Time of Concentration

The time shall be determined as explained in Section 1101.2.2. A minimum time of concentration of 15 minutes to the first ditch catch basin and 10 minutes to the first pavement inlet shall be used. The actual calculated time of concentration shall be used when values greater than these minimums occur. 1104.4.5 Pipe Roughness Coefficient

A Manning’s “n” of 0.015 shall be used for sewers 60 inches in diameter and under, and 0.013 for larger sewers. The basic “n” value for smooth pipe, concrete, vitrified clay, bituminous lined corrugated steel or thermoplastic is 0.012. The increased values are recommended for sewers to compensate for minor head losses incurred at catch basins, inlets and manholes located in a storm sewer system. 1104.4.6 Minimum Storm Sewer Pipe Size

A minimum pipe diameter of 15 inches shall be used for Freeways and Freeway ramps (Where an existing storm sewer is to remain in service, it is not necessary to replace, hydraulically adequate pipes to meet this criterion) and 12 inches for other highways. 1104.4.7 Maximum Storm Sewer Slope

For storm sewers designated as Type B or Type C, the maximum slope is 25%. For storm sewers with slopes that exceed 25%, designate as Type F. 1104.5 Hydraulic Design Procedure

With the layout suggested in Section 1104.3, start with the upper catch basin or inlet and determine the value of CA for the contributing flow (CA is the product of the weighted coefficient of runoff and the drainage area). Next, determine the time of concentration for the first area and the corresponding rainfall intensity “i” from the proper curve shown on Figure 1101-2. The design discharge “Q” to use to determine the required size of the first sewer from MH No. 1 to MH No. 2 is the product of Ca x i [0.0028CA x i]. At manhole No. 2, determine the value of CA for the additional area contributing at that point and add to the CA for MH No. 1. Compute the time of flow in the storm sewer from MH No.1 to MH No. 2 in minutes and add to the time of concentration at MH No. 1. Check the time of concentration for the area contributing to MH No. 2, and use the larger of the two as the duration for the new value of rainfall intensity for computing the design flow from MH No. 2 to MH No. 3. It is obvious that the process is quite involved, and a storm sewer computation sheet similar to that provided in the Appendix shall be used to tabulate the required information. The calculations for lateral connections to the longitudinal trunk sewer should be tabulated separately from the trunk sewer calculations. Software developed by ODOT (CDSS) is available online and can be used for these calculations. StormCAD may also be used for these calculations. Other software packages may be utilized with approval from OHE.

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Drainage Design Procedures 1104.6 Combined Sanitary Sewer Separation

When the Combined Sanitary Authority is under court order to address frequent overflow of the sanitary system due to storm sewer impacts, every effort should be made to furnish an exclusive outfall for the storm sewer when feasible. Coordination with the Local is required. While adherence to Local drainage standards is not applicable for ODOT owned and maintained drainage assets it may be possible for the Department to incorporate the needs of the local entity subject to review and approval of OHE. The Department will fund storm sewer conduit and drainage structures to ensure positive drainage of the roadway when a separation is feasible. Conduit and structures required for sanitary sewer will be funded by the Local. All conduit located outside of the Department owned right-of-way will be funded by the Local.

Conduit will be furnished for the most feasible and direct route of storm or sanitary sewer as determined by the Department.

1105 Roadway Culverts

1105.1 General

A culvert generally carries a natural stream under the highway embankment. The culvert horizontal and vertical alignment should approximate that of the natural channel and thereby minimize stream impacts and the need for channel relocations. Ensure the upstream invert is not below the natural channel unless the culvert has depressed inverts, a paved depressed approach apron, or an improved inlet. Optimum culvert design (i.e., best hydraulic performance and least environmental impacts) occurs when the roadway alignment is normal to the flow in the channel and is located on a relatively straight and stable section of the channel. Roadway alignment needs to be considered early in the design process to provide optimum culvert design. The proposed roadway should avoid stream confluences. Culverts should not be placed on skews in excess of 45º or as further limited in Section 1008. Check the design with a single-cell round pipe as a first choice. In cases where required cover or discharge precludes a round pipe, select a shape that reduces the vertical requirements while maintaining the hydraulic capacity. Check the design with the following shapes in order of minimum cost to increasing cost: single-cell elliptical concrete, metal pipe-arch, prefabricated box culvert or three-sided structure. For justification of multiple cell culverts, see Section 1105.7.2. In general, maintain the existing upstream and downstream hydraulics when replacing an existing culvert. In cases where these parameters must be modified, evaluate any upstream and downstream impacts. Culvert location should perpetuate existing drainage patterns (depth of flow, direction of flow, overbank flow) to the maximum extent practicable. Diversion of substantial volumes of flow requires regulatory consideration and possible actionable damage. Label the depth or elevation of the Ordinary High Water Mark (OHWM) for jurisdictional waterways on the Culvert Detail Sheet for all culverts. The depth is measured from the centerline of the waterway. The OHWM is calculated per Section1105.6.13 or determined by the Office of Environmental Services. 1105.2 Stream Protection

Stream protection practices are provided to improve stream channel stability. Erosion of the stream channel can migrate upstream and downstream without proper protection at the structure.

11-20 January 2015

Drainage Design Procedures Provide stream protection practices (water quantity treatment) for all culvert projects when the project earth disturbing acreage exceeds the thresholds for post-construction Best Management Practices (BMP) outlined in Section 1115.2. Exceptions for providing stream protection to meet post-construction BMP requirements are noted in Section 1115.3. In addition to post-construction BMP requirements, waterway permit conditions and site specific features may require the use of practices described throughout this Section. Stream protection for culvert projects is provided through the use of the following practices:

• Bankfull discharge design • Depressed culvert inverts • Paved depressed approach aprons • Flood plain culverts

For existing culvert replacements, inspect the channel for erosion that has caused undercutting or downcutting at the inlet of the culvert. At locations with evidence of undercutting or downcutting, provide a concrete apron according to Section 1106.3 at the inlet and outlet of the culvert to restore previous stream elevations and provide stream protection. The use of each stream protection practice is limited based on project specific conditions. If the stream protection practices listed above are not applicable or available based on project type, site constraints or limitations, the project is not exempt from providing stream protection BMP. Other methods of stream protection must be used. In addition to the stream protection practices described within this Section, the following post-construction storm water BMP may be utilized within available right-of-way or right-of-way being obtained for roadway purposes to provide stream protection and treat storm water runoff when the project earth disturbed area is equal to or exceeds one acre:

• Extended Detention (See Section 1117.3) • Retention Basin (See Section 1117.4) • Bioretention Cell (See Section 1117.5) • Infiltration Methods (See Section 1117.6) • Constructed Wetlands (See Section 1117.7)

See Sections 1115 through 1117 for further information concerning post-construction storm water BMPs. 1105.2.1 Bankfull Discharge Design

Culverts utilizing Bankfull Discharge Design are required to convey the bankfull discharge with minimum change in the stream energy for the adjoining channel sections when compared to the existing conditions. The proposed culvert will minimize the impact to the stream channel by closely matching the existing depth of flow with the proposed depth of flow for the bankfull discharge. Provide Bankfull Discharge Design for all culverts conveying streams with the following exceptions:

• The culvert is a replacement structure (permitted under the Regional General Permit for ODOT or a Nationwide Permit #3 - Maintenance).

• The culvert rise is 30" or less.

• The culvert is located on bedrock.

• The culvert slope exceeds 1%.

January 2015 11-21

Drainage Design Procedures If multiple cell culverts are provided, ensure only one culvert conveys the bankfull discharge. Place the invert of additional culverts at the water surface elevation generated by the bankfull discharge. Use the following design steps when performing a bankfull discharge design:

1. Determine the bankfull discharge using USGS report 2005-5153, “Bankfull Characteristics of Ohio Streams and Their Relation To Peak Streamflows”. Use the regression equation that utilizes USGS map-based explanatory variables. The report can be obtained from USGS at: http://pubs.usgs.gov/sir/2005/5153/.

2. Determine the culvert size from traditional culvert hydraulic design. 3. Depress the culvert invert according to Section 1105.2.2. 4. Determine the depth of flow for the pre-developed channel using the bankfull discharge at

locations 25 feet before the culvert inlet, at the culvert, and 25 feet beyond the culvert outlet. Determine the depth of flow for the bankfull discharge based on field-obtained stream cross-sections and the use of a standard step-backwater water-surface profile model such as HEC-RAS or the use of other software capable of calculating depth of flow based on Manning’s equation.

5. Determine the depth of flow for the post-developed channel using the bankfull discharge at the

same locations identified in Step 4 through use of a standard step-backwater water-surface profile model such as HEC-RAS or the use of other software capable of calculating depth of flow based on Manning’s equation. The cross section at the culvert will reflect the geometry of the culvert.

6. Compare the depth of flow from step 4 to step 5. Adjust the culvert dimensions until the post-

developed condition flow depth (Step 5) is approximately equal to the pre-developed flow depth (Step 4).

7. Add flood plain culverts if required (see section 1105.2.4).

8. Determine if the culvert meets the required hydraulic design controls. Upsize the culvert as

required 1105.2.2 Depressed Culvert Inverts

Provide depressed inverts for all culverts designed to convey the Bankfull Discharge Design.

Depressed culvert inverts will produce a natural channel bottom within the culvert. The natural channel bottom provides a substrate for passage of migratory species. The depressed culvert will fill naturally, such that the channel bed in the culvert will be continuous with the adjacent channel sections. Verify that the culvert meets the required hydraulic design controls realizing that the portion of the culvert depressed will eventually fill with natural substrates. Upsize the culvert as required. End treatments for culverts with depressed inverts consist of Item 601 Riprap, 6” Reinforced Concrete Slab with a cutoff wall on both inlet and outlet ends. See standard construction drawing DM-1.1 for details. Depress the culvert invert according to Table 1105-1: 11-22 January 2015

http://pubs.usgs.gov/sir/2005/5153/


Table 1105-1 Type A Conduit

Invert Depression Pipe Diameter or Rise Depression

<36” None 36”-60” 6” 66”-120” 12” 126”-180” 18” 186”-252” 24”

>252” 30” Modifications to the standard headwalls are not necessary for the depression depths noted above. Depressed inverts are not required for precast reinforced concrete three-sided flat-topped culverts with a natural channel bottom. 1105.2.3 Paved Depressed Approach Aprons

In many cases, the hydraulic operation of a culvert can be improved by depressing the flowline at the entrance below the channel flowline. The drop-down will alleviate a minimum cover condition, provide for additional headwater depth, and decrease the culvert outlet velocity by reducing the culvert slope. The abrupt change in natural channel slope is effected with a short length of concrete paving to prevent downcutting of the stream. The dimensions of the slab are site specific. However, for ease of construction, a 2:1 downslope should be used as the maximum descending slope. A 3-foot length of paving should be provided along the natural channel slope prior to the drop-down. A cut-off wall must be provided at the upstream end. In general, limit drop-down entrances to 4 feet, or one pipe diameter or rise, whichever is greater. The Federal Highway Administration has conducted extensive research and studies of paved depressed approach aprons, and recommended design procedures are included in Hydraulic Design Series No. 5, "Hydraulic Design of Highway Culverts." 1105.2.4 Flood Plain Culverts

For all new bankfull culvert installations, consider the use of flood plain culverts. In wide flood plains, the installation of a new single culvert constricts the flow of water at the entrance section. The concentrated outflow from the culvert can initiate downstream channel degradation. Flood plain culverts can be used to minimize the effects of this new concentrated discharge by spreading the discharge throughout the flood plain or flood prone area on the outlet side of the culvert. Provide flood plain culverts when the flood plain width is greater than two (2) times the width produced by the bankfull discharge design. Flood plain culverts are installed adjacent to the single culvert. Place flood plain culvert inverts at the water surface elevation that is generated by the bankfull discharge design. Locate the flood plain culverts within the flood plain at a location well beyond the single culvert. Furnish a minimum of two flood plain culverts. Figure 1102-2 illustrates the location of flood plain culverts with respect to the bankfull channel and flood plain. Flood plain culverts are not hydraulically designed or accounted for in the hydraulic design of the single culvert. Use Figure 1002-1 (“other” column) to determine the required diameter. The line and grade of the culvert should approximate that of the natural flood plain.

January 2015 11-23

Drainage Design Procedures 1105.2.5 Energy Control Structures

Provide energy control structures for all culverts with an outlet velocity greater than five feet per second. The use of energy control structures does not constitute water quantity treatment for post-construction BMP purposes. An energy control structure reduces the amount of erosive energy generated by a culvert. Use the following for an energy control structure:

• Broken-Back Culvert • Rock Channel Protection • Energy dissipator (Riprap Basin) • Drop Structure

Provide an energy dissipator when the outlet velocity exceeds the values shown in Figure 1107-1. Energy dissipaters create a forced hydraulic jump within the structure or immediately downstream of the structure, thus reducing the flow velocity. FHWA Hydraulic Engineering Circular No. 14 provides design guidance and procedures for various energy dissipators. A riprap basin is the most cost effective energy dissipator. Contact OHE prior to using an energy dissipator. 1105.3 Types of Culvert Flow

Laboratory tests sponsored by the FHWA have established two general types of culvert flow: (1) flow with inlet control, or (2) flow with outlet control. Nomographs have been prepared for use in the determination of culvert headwater for the appropriate control. Under inlet control, the headwater “HWI” is directly related to the cross-sectional area of the culvert barrel and the inlet geometry. Under outlet control, the headwater “HWO” is further influenced by tailwater depth in the outlet channel and the slope, length and roughness of the culvert barrel. As shown in Figure 1105-3, culverts operate with a free water surface if the headwater is equal to or less than 1.2D, and with a submerged entrance if the headwater is greater than 1.2D, where D is the diameter or rise of the pipe. 1105.4 Design Procedure

1105.4.1 General

The design of a culvert involves a determination of the appropriate design and check discharges. The process begins with a delineation of the drainage area, in acres [hectares], on a suitable topographic map. The design discharge “Q” for most culvert drainage areas will be obtained by procedures described in Section 1003.1.2 of this manual. The Rational method should be used to obtain the discharge from small and other unusual drainage areas as noted in Section 1101.2.2 A representative cross-section of the embankment at the proposed culvert site, along with a profile of the natural stream or ground line, will be required to determine the approximate length and slope of the culvert. 1105.4.2 Hydraulic Analysis

The hydraulic analysis of a culvert, including a determination of the headwater depth and outlet velocity for the design discharge, is simplified by the use of Pipe Flow Charts and the headwater and head nomographs noted in Section 1105.4. The charts are included with the Drainage Design Aids, beginning with Figure 1100-200. To preclude the need for a determination of the probable type of flow under which a culvert will operate for a given set of conditions, the headwater depths may be computed using the nomographs for both inlet

11-24 January 2015

Drainage Design Procedures and outlet control. The size of pipe is then selected by using the control giving the higher headwater limitation. The relationship of the headwater to the diameter or height of the culvert “HW/D” is read directly from the inlet control nomograph and the HWI equals that value multiplied by D. HWO is computed by the equation HWO=H+ho - SoL.;/ The loss of head “H” is read from the flowing-full nomograph and the tailwater depth “ho”, is the greater of either the normal depth of flow in the outlet channel or the depth as flow passes through the outlet of the pipe, calculated as (dc+D)/2. D is the diameter or rise of the culvert and dc is the critical depth of flow which may be read from the critical depth curve shown on each Pipe Flow Chart. The above procedure is reasonably accurate for the majority of culvert flow conditions. For culverts operating with outlet control (see Figure 1105-1, Class 1-A and 1-B), where the calculated headwater (using the appropriate nomograph) is less than 0.75D, a backwater analysis can be justified and is recommended. A culvert analysis sheet similar to that provided in the Appendix shall be used to tabulate all the pertinent factors required to determine the controlling headwater for each culvert type being considered for a given location. The analysis sheet includes other information valuable to the reviewer and it is to be included with other supporting data for required review submissions. Hydraulic analysis of culverts may also be performed utilizing the Federal Highway Administration Hydraulic Design Series No. 5, Hydraulic Design of Highway Culverts. Computer programs such as FHWA HY-8 or ODOT’s CDSS software package may be used. CDSS may be downloaded from the Hydraulics website. For replacement projects, an analysis of the existing structure shall be performed. Use the same analysis method when comparing the existing and proposed structures. For bridge replacements, the acceptable method of hydraulic analysis is HEC-RAS. 1105.5 Use of Nomographs

1105.5.1 Outlet Control

To determine the loss of head “H” for a given concrete pipe culvert with a grove-end entrance and discharge “Q”, proceed as follows: By straight line, connect culvert size with ke=0.2 (length scale) and obtain a point on the turning line. Connect the turning line point with the computed discharge “Q” and read the head loss “H”. Follow the same procedure for a corrugated metal pipe except using ke=0.9 (length scale). The ke value for additional shapes can be found in the Federal Highway Administration publication referenced in Section 1105.3.1. Should the roughness coefficient “n” of the proposed pipe differ from that shown on the chart, adjust the measured culvert length by the length factor given on Design Aid Figure 1100-247. For an example, see Drainage Design Aid Figure 1100-247. The Federal Highway Administration publication referenced in Section 1105.3.1 offers nomographs for culvert shapes not available in the Drainage Design Aids. Their use is recommended for special culvert shapes. 1105.5.2 Inlet Control

To determine the headwater “HW” for a given discharge “Q”, size and type of culvert, proceed as follows using appropriate Figures 1100-245, 1100-246 (Drainage Design Aids). Use Figure 1100-245 for a round corrugated metal pipe culvert and Figure 1100-246 for a round smooth-lined pipe culvert. By a straight line, connect the culvert size with the discharge “Q”, extend a diagonal line to Scale (1) and thence by horizontal line to Scale (3). Based on a groove-end entrance and a Standard HW-2.1 headwall recommended for concrete pipe culverts, the HW/D relationship is obtained by an average of the (2) and (3) Scale values. Follow the same procedure for a corrugated metal pipe with a Standard HW-2.2

January 2015 11-25

Drainage Design Procedures headwall, where HW/D is the average values read from Scales (1) and (3). Use Scale (2) for the HW/D relationship for concrete box culverts. 1105.6 Design Criteria


The design frequency shall be as stated in Section 1004.2 It should be noted that a Flood Hazard Evaluation using a check discharge based on the 100-year flood frequency shall be made for all culverts as noted in Section 1005.2.1. 1105.6.2 Maximum Allowable Headwater

See Section 1006. 1105.6.3 Method Used to Estimate Storm Discharge

See Sections 1003 and 1101. 1105.6.4 Scale of Topographic Mapping Used to Delineate Contributing Drainage Areas

See Section 1101.1 1105.6.5 Manning’s Roughness Coefficient “n”

The “n” values for corrugated metal pipe are given in Figure 1105-2. The “n” value for all smooth flow pipe is 0.012. Use a weighted Manning’s n for bankfull designed culverts or analyzing older culverts with sediment deposition. 1105.6.6 Entrance Loss Coefficient “ke”

See Table 1105-2 or Appendix D of Federal Highway Hydraulic Design Series No. 5, "Hydraulic Design of Roadway Culverts.

Table 1105-2 Type A Conduit

Entrance Loss Coefficient ke

Type of Pipe Headwall Type Full One-Half None

Concrete, Vitrified (thick wall) *

0.2 0.2 0.2

Corrugated Metal (thin wall)

0.25** 0.9 0.9

* groove end entrance ** with beveled entrance

Plastic conduits without a welded bell inlet will be designed as a corrugated metal conduit. Plastic conduits with a welded bell inlet will be designed as a concrete conduit. In both cases, the mannings “n” value for plastic is 0.012. 1105.6.7 Minimum Cover

See Section 1008 1105.6.8 Maximum Cover

See Section 1008 11-26 January 2015

Drainage Design Procedures 1105.6.9 Maximum Allowable Outlet Velocity

See Figure 1107-1 1105.6.10 Headwall Type

See Section 1106.2 1105.6.11 Contacts With County Engineer

Contact shall be made with the County Engineer at the beginning of the design process to ascertain ditch cleanout grades and watersheds, and the design shall be based on that information. Form LD-33 (available in the Appendix) shall be used to document approval. 1105.6.12 Minimum Pipe Size

As specified in Section 1002.3.1 1105.6.13 Ordinary High Water Mark

Calculate the OHWM using the 2 year depth of flow in the stream or channel or as determined by the Office of Environmental Services. 1105.7 Special Considerations

The following are special conditions that will be encountered in the hydraulic design of culverts that warrant clarification. Apply appropriate stream protection practices as described in Section 1105.2 when using special design considerations. 1105.7.1 Tailwater

Tailwater at a culvert outlet can greatly affect the size of culvert required at a specific site. For this reason a proper evaluation shall be made of the outlet channel so that a reasonable estimate of the tailwater can be calculated. A determination of the normal depth of flow in the outlet channel, when the culvert is discharging the design flow, normally establishes the culvert tailwater. A close examination of the downstream channel may however, reveal a temporary or permanent obstruction that will control the operation of the culvert. In some cases, the culvert will outlet near a river or other fluctuating water surface stream that could control its operation. Where that drainage area of the culvert is very much less than the receiving watercourse (i.e. 100 times) the effect of the receiving watercourse generally may be disregarded. Where the drainage areas of the culvert and receiving watercourse are nearly equal, concurrent flood peaks may be assumed. Where there is a significant, but not excessive, difference in the drainage area of the culvert and receiving stream, the following design procedure should be used and the culvert sized using the combination that results in the highest headwater. A. Compute the culvert headwater using the proper design frequency for the culvert and a lesser

frequency for the receiving stream water surface elevation (i.e. culvert tailwater elevation) depending upon the difference in drainage areas; say a 25-year culvert and a 10-year stream.

B. Use 10-year frequency for the culvert and 25-year for the stream.

January 2015 11-27

Drainage Design Procedures In some locations, a high tailwater will control the operation of a culvert to such an extent that a substantial increase in pipe size will be required for a negligible decrease in the headwater elevation. For this case, the culvert size should be based on a practical tailwater elevation (e.g. [dc+D]/2). 1105.7.2 Multiple Cell Culverts

A single-cell culvert should be the designer’s first choice within practical limitations. Occasionally, low headwater requirements, high fills, or bankfull design will create the need for multiple cells. For these cases, it is desirable to limit the number of cells to two. Experience has proven that multiple cells well aligned with a relatively straight channel, will operate satisfactory. However, a bend in the immediate upstream channel may cause the inside cell to collect debris during normal periods of runoff and thereby substantially reduce the capacity of the culvert. 1105.7.3 Improved Inlets

Consider improved inlets attached to the entrance end of the culvert to reduce headwater or culvert size. The improved inlet will alleviate a minimum cover condition and provide for additional headwater depth. Culverts on relatively steep slopes and controlled by inlet control can see a reduction in the culvert size by furnishing an improved inlet. Consider the following two general types of inlets in the following order: A. Side-taper - A tapered end section from a round to an oval shape for a pipe, or a square to a

rectangular shape for a prefabricated box. The length of the taper section is usually made 1.5 times the diameter or rise of the culvert.

B. Slope-taper - A combination of side-taper preceded by a drop in the culvert flow line. The drop can

be similar to a paved drop-down entrance or a more sophisticated reinforced concrete drop provided by a formed cast-in-place section with vertical sides.

The improved inlet has the advantage of admitting more flow and thereby tending to fill the culvert barrel and reduce the culvert outlet velocity. The savings in culvert cost must justify the additional cost of the improved inlet. The Federal Highway Administration has conducted extensive research and studies of improved inlets, and recommended design procedures are included in Hydraulic Engineering Circular No. 13, "Hydraulic Design of Improved Inlets for Culverts."

1106 End Treatments

1106.1 General

Headwalls, or other approved end finishes, shall be provided at the open ends of all Type A, B and C conduits. Headwalls should also be provided for Type D conduits greater than 24 inches in diameter or rise. Generally, headwalls are not recommended for Type E and F conduits. In order to reduce the entrance loss in culverts, the bell end should be located upstream and the spigot end should be located downstream. Details shown in the plan should convey this to the Contractor when necessary. Figures 1106-2 and 1106-3 show typical end details for a concrete box culvert. 1106.1.1 Usage

The selection of the headwall type is based on safety and economics. Standard HW-2.1 and 2.2 half-height headwalls are recommended for round, elliptical, or pipe arch culverts where a clear zone is provided. Full height headwalls should be provided where a significant reduction in culvert length can be realized with large-span culverts (10 feet or greater) with foreslopes flatter than 2:1 or where right-of-way

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Drainage Design Procedures limits the culvert length. Full-height headwalls shall be provided for prefabricated box culverts and three-sided structures. The use of special end treatments may be required by Section 602.6 of Volume 1, Roadway Design. Details are available from the Office of Hydraulic Engineering. Justification for the use of this type of end treatment shall accompany the request for details. Miter-cut (step-bevel) end sections, when required, shall be shown on the Culvert Detail Sheet. When half-height headwalls are provided, they should be built perpendicular to the end of the conduit to eliminate the need for a skew cut. In addition to the required headwall, the upper, or exposed, half of conduits having a diameter or rise greater than or equal to 126 inches shall be miter-cut (step-bevel) to fit the embankment slope. 1106.1.2 End Treatment Grading

The prevailing embankment slope shall be projected to the back edge of the top of the headwall to establish the required culvert length as shown in Figure 1106-1. When the roadway foreslopes are flatter than 2:1, a 2:1 slope shall be provided from the back edge of the top of the headwall to a minimum of 1 foot, with 2 feet, above the top of the culvert. The change in embankment slope shall be warped on each side of the conduit to fit the prevailing slope. In no case shall the distance from the pavement edge to the point where the embankment slope changes to 2:1 be less than the design clear zone width (see Section 601, Volume 1, Roadway Design) unless guardrail is provided. Clear zone grading should only be provided at culverts when the requirements of Section 307.2.1 of Volume 1, Roadway Design are met. The prevailing embankment slope shall be warped on either side of a skewed culvert to assure equivalent soil loading and proper side support of the pipe. This is especially true for flexible pipes with large skews and/or large diameters. 1106.2 Headwall Types

1106.2.1 Half-Height Headwalls

If the size of the conduit exceeds that shown in the Standard Construction Drawing HW-2.1 and HW-2.2 tables, the dimensions shown in the tables may be expanded to accommodate the larger size conduits. Payment for half-height headwalls shall be on a cubic yard basis for Item 602, Concrete Masonry. Masonry quantities for standard half-height headwalls may be obtained from the appropriate standard construction drawing. The quantity of concrete masonry provided in the plans shall be based on the pipe alternate requiring the largest quantity of concrete masonry. 1106.2.2 Full-Height Headwalls

The appropriate full-height headwall for round pipes shown on Standard Construction Drawing HW-1.1 may be considered at the entrance end, when the savings in the reduced size and length of the conduit will offset the additional cost of the headwall. This will most likely apply where corrugated steel pipe is specified, due to cover or size requirements, and the bevel provided for the full-height headwall will substantially reduce the entrance loss. Dimensions of full-height headwalls may be expanded to accommodate pipe sizes larger than 84 inches. Design full-height headwalls for box, 3-sided and arch culverts per Section 300 of the Bridge Design Manual and the latest “AASHTO LRFD Bridge Design Specifications”. Payment for non-standard full-height headwalls is on a cubic yard basis for Item 511 and pounds of Item 509. Subdivide the quantities for non-standard full-height headwalls in to quantities for headwalls, wingwalls and footers and add plan note D118 to the plans. Include appropriate plan notes from Section 600 of the Bridge Design Manual in the project plans.

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Drainage Design Procedures An investigation of the supporting foundation material shall be conducted and the bearing resistance of the foundation material estimated. The level of detail required for the foundation investigation shall be commensurate with the importance of the structure. Such information shall be submitted for all proposed full-height headwall installations and submitted with the Stage 1 review. The inlet wingwall footings of full-height headwalls shall be armored with Type B rock channel protection, with filter, to preclude scour. 1106.3 Concrete Apron

Provide a reinforced concrete riprap cutoff wall, as shown on Standard Construction Drawings DM-1.1 when the depth of the rock channel protection (if necessary), including the 6 inch granular filter, exceeds the depth of the headwall. Provide concrete riprap at the inlet end of the culvert where the existing culvert has been undercut. Concrete riprap shall be in accordance with Section 1105.2.3. Concrete riprap is not necessary at the inlet of culverts with full height headwalls that have a footing toe extending 3.5 feet or more below proposed channel grade.

1107 Rock Channel Protection (RCP)

1107.1 General

RCP is used to control erosion and as a scour countermeasure. It is used at the outlet of culverts and storm sewers, or for lining ditches on steep grades. It is used as a scour countermeasure at wingwalls of full-height headwalls, along footings of 3-sided structures, corner cones, and under bridges. 1107.2 Culvert RCP Types

There are four types of RCP that are used in various situations. The use of the proper type at culvert and storm sewer outlets can be determined from Figure 1107-1. Type A is generally used beyond the outlet of the larger conduits having outlet velocities in excess of 12 feet per second and Type B and C for conduits having an aggregate filter where the protected slope is steeper than 3:1. A filter should always be specified to prevent soil piping through the rock. A fabric filter is appropriate in most cases. An aggregate filter should be used when the RCP is under water. The cost of the filter is included in the unit bid price for Item 601 Rock Channel Protection with Filter. 1107.3 Bridge RCP

Furnish RCP armor for bridges over waterways at the following locations:

A. The entire spill-through slope

B. Front side of abutments and wingwalls

C. Corner cones

Use the following table to determine the Type of RCP to use:

Channel Mean Velocity (ft/s)

RCP Type

Thickness

0-8

C

2’-0”

8-10

B

2’-6”

above 10

A

3’-0”

11-30 January 2015

Drainage Design Procedures Special circumstances such as protection on the outside of curves or in northern regions of the state on pooled water where ice flow is a concern may require greater rock thickness.

Show on the Site Plan the locations, length, and the top of slope elevations for the RCP. Show the RCP in greater detail in the roadway section in conjunction with the channel plans. It is more economical to provide bank protection during the initial construction in order to provide sufficient embankment protection to minimize future maintenance.

Limit stream channel excavation to that portion of the channel one foot above normal water elevation in order to minimize intrusion and to preserve the natural low water channel.

1108 Agricultural Drainage

1108.1 Farm Drain Crossings

Where it is necessary to continue an existing farm drain crossing under the highway, the pipe shall be Type B Conduit, one commercial size larger than the existing farm drain within the right-of-way limits. Occasionally, it will be desirable to provide a farm drain crossing under a highway on new location to satisfy the future need for adequate farm drainage. It is recognized that the required length of a Type B Conduit will provide a betterment for the property owner, but it does preclude the need for a much more expensive crossing after the highway is built. Such a crossing is considered a “blind” and the cost of the installation, including suitable terminal markings at the right-of-way lines, will generally not be eligible for federal participation. 1108.2 Farm Drain Outlets

Existing farm drains that outlet through the backslope of the roadway ditch shall terminate with a minimum length of 10 feet of equivalent size Type F conduit. When outletting existing plastic farm drains, one size larger Type F conduit shall be used. An Animal Guard and Erosion Control Pad as shown on Standard Construction Drawing DM-1.1 shall be provided. To provide for possible sedimentation, the invert of the Type F conduit shall be a minimum of 6 inches, with 12 inches being desirable, above the ditch flow line.

1109 Longitudinal Sewer Location

1109.1 Under Pavement

Longitudinal sewers will not be permitted under the pavement of a limited or controlled access facility. Also, the length of transverse sewers under pavements shall be held to a minimum, with the objective of having no manholes in the pavement. Contact OHE if this cannot be accommodated to discuss a possible resolution. For other facilities, storm sewers should be located outside the limits of the pavement. However, in locations where this would create conflicts with existing utilities (e.g. waterlines, sanitary sewers, gas lines, etc.) the storm sewer may be located under the pavement. Care should be taken to avoid placing manholes in vehicle wheel-paths or within an intersection. Place the center of the manhole in the lane when feasible. Where an out-to-out clearance of 5 feet cannot be provided between parallel storm and sanitary sewers, premium joints shall be provided on the storm sewer. 1109.2 Under Paved Shoulder

The above shall also apply to paved shoulder areas, unless it is determined that the cost of any other possible location is prohibitive.

January 2015 11-31

Drainage Design Procedures 1109.3 Approval

Exceptions to the above shall be submitted in the early stages of the design to the Office of Hydraulic Engineering for review and approval.

1110 Reinforced Concrete Radius Pipe and Box Sections

1110.1 General

To comply with the capabilities of manufacturers to provide satisfactory and economical radius pipe or box sections, a minimum radius of 100 feet shall be specified. The method of manufacturing the radius pipe or box sections will be an option of the producer, subject to inspection and approval by the Ohio Department of Transportation, Office of Materials Management. As an alternate to radius pipe, pipe specials may be specified to negotiate the specified radius, provided they do not reduce the hydraulic performance established by the initial design. The bends shall be located so that they shall closely follow the alignment of the radius pipe.

1111 Sanitary Sewers

1111.1 General

Any sanitary sewer, whether new or relocated, shall be constructed using resilient and flexible gasket joints, in accordance with Construction and Material Specification 706.11 for circular concrete pipe or 706.12 for clay pipe. Permissible thermoplastic pipes shall also be specified. Discharges of treated sanitary flow from abutting property into highway drainage systems are only permitted if the discharge is authorized by the Local Health Department. 1111.2 Manholes

All new manholes for sanitary sewer lines shall be built in accordance with the Standard Construction Drawings. Precast manholes shall have joints in accordance with 706.11 of the Construction and Material Specifications.

1112 Notice of Intent (NOI)

1112.1 General

A NOI is a one-page application form for requesting coverage under a National Pollutant Discharge Elimination System (NPDES) general permit for storm water discharges from Ohio EPA. The applicant(s) must certify their intention to comply with the NPDES general permit by submitting a NOI. Submit a NOI for all projects where combined Contractor and Project Earth Disturbing Activity (EDA) are one acre or more. In addition, when the combined Project and estimated Contractor EDA are just less than one acre, the project designer may choose to increase the estimated Contractor EDA to avoid the possibility of work on the project being initiated without a NOI. Earth disturbing activity is defined as any activity that exposes bare ground or an erodible material to storm water and anywhere Item 659 Seeding, or Item 660 Sodding is being furnished. Routine Maintenance Projects, as defined by Section 1112.2, do not require a NOI. The Total Earth Disturbing Activity acreage, which includes the Project Earth Disturbing Activity acreage (earth disturbed area within the project construction limits) and the Contractor Earth Disturbing Activity acreage such as: field offices, batch plants, and borrow/waste pits, shall be estimated. The location and size of the Contractor Activities can be estimated using the NOI Acreage Calculation Form (Figure 1112-1).

11-32 January 2015

Drainage Design Procedures Non-contiguous portions of projects sold under one contract, such as multiple culvert replacements, may be treated as separate projects for the purposes of obtaining an NOI . If the project sites are located ¼ mile or more apart and the areas between the activities are not being disturbed, the sites can be considered separate. If each site is below the project earth disturbed area threshold of one acre of EDA, no post-construction BMP or NOI will be required. If one or more individual sites meet the project earth disturbed area thresholds, an NOI is required for the project sites that exceed the EDA threshold. The NOI application should reflect the Project and Contractor EDA for all project sites that exceed the threshold. Post-construction BMPs will be required only at the individual project sites that exceed the Project EDA threshold. Non-contiguous multiple part projects (i.e. Part 1/Part 2) sold as one project should be evaluated with respect to each Part. Parts that meet the definition in Section 1112.2 for Routine Maintenance Projects or have a project EDA under one acre do not need to be included in the disturbed acreage calculations for determining the need for a NOI or post-construction BMP. Post-construction BMPs will be required only for individual parts that exceed the Project EDA threshold. Follow standard NOI procedures for a Project Part with routine maintenance activities exceeding five acres or a Project Part that includes construction (non-routine maintenance) activities. For projects where all runoff is collected in a combined sewer, a NOI is not required. However, coordination with the agency responsible for the receiving treatment plant is required. Prepare a Project Site Plan as required by Location and Design, Volume 3, Section 1308 for all projects that require a NOI. 1112.2 Routine Maintenance Project

For the purposes of submitting for coverage under a NPDES permit, a Routine Maintenance Project is one in which all of the Project Earth Disturbing Activities are routine operations that do not change the line, grade, or the hydraulic capacity of the facility and involve total earth disturbing activities of less than 5 acres. Permanent erosion control items shall be included in the plans, if required. Routine maintenance projects do not require a NOI. Projects with five or more acres of earth disturbed area cannot be classified as Routine Maintenance Projects. These projects require a NOI and post-construction BMPs, regardless of work type. The following activities are considered routine maintenance activities:

• Abutment Repairs - repairs to bridge abutments • Bridge Deck Overlays - replacing the wearing surface on bridges • Bridge Deck Replacement - replacing the entire deck on bridge • Chip Sealing - placing asphalt or polymer binder and stone on existing paved roadways • Fence Repair / Replacement - repairing or replacing existing fencing and/or posts • Lighting Maintenance • Loop Detector Repairs - repairing loop detectors in existing pavement • Pothole Filling • Tree/brush Removal • Signal Installation / Maintenance - installing / repairing / replacing traffic signals and poles where

previous ones existed • Signing Maintenance - repairing / replacing traffic signs and posts • Noise Wall Repair • Full Depth Pavement Repairs - isolated repairs of pavement build-up down to subgrade • Partial Depth Pavement Repairs - isolated repairs of surface courses of pavement • Linear Grading - reshaping of graded shoulders to establish proper drainage away from

pavement • Berm Repair or Topsoil placement along shoulders - placing berm material or topsoil on

shoulders adjacent to pavement to eliminate drop-offs. • Ditch Cleanout - maintaining or restoring original flow line and cross-section only

January 2015 11-33


• Guardrail Installation / Replacement - installing / repairing with minor grading work to create proper grade for end assemblies where previous guardrail existed.

• Culvert Replacement - replacing a culvert with same line, grade and hydraulic capacity; must be within parameters of the USAC Nationwide Permit #3.

• Culvert Repair / Lining - repairing or lining existing culvert maintaining same line, grade and hydraulic capacity, must be within parameters of the USAC Nationwide Permit #3

• Resurfacing - replacing several inches of asphalt wearing course by milling existing asphalt and replacing with new.

• Curb Repairs - repairing existing curbing along a roadway. • Sidewalk – replacement of sidewalk without other drainage or roadway improvements. • Isolated slide repairs.

Post construction storm water best management practices are not required for routine maintenance projects. 1112.3 Watershed Specific NOI Requirements

Additional requirements for projects located in certain designated watersheds are required by Ohio EPA. These projects require coverage under an Ohio EPA watershed specific NPDES permit. Coordinate projects in the following watersheds with Central Office – Office of Hydraulic Engineering:

• Big Darby Creek (entire watershed) • Olentangy River (portion of watershed as regulated under permit number OHC200001)

In addition to post-construction BMP requirements, watershed specific NPDES permits include the following requirements:

• Groundwater Recharge Mitigation, if applicable • Riparian Setback Mitigation • Temporary Sediment Basin Locations • Ohio EPA review and approval of the Storm Water Pollution Prevention Plan (SWPPP)

Provide groundwater recharge calculations, riparian setback calculations, and temporary sediment basin locations to Central Office – Office of Hydraulic Engineering with the BMP submittals as outlined in Section 1116.2. Groundwater recharge calculations and riparian setback calculations shall be based on impacts outside the existing roadway right-of-way. Determine the riparian setback limits according to the Permit and identify the setback limits on the Project Site Plan. Mitigation for groundwater and riparian setback will be determined through coordination between the District, Central Office – Office of Hydraulic Engineering and Ohio EPA prior to submittal of the NOI application. Determine soil types required for groundwater recharge calculations using the NRCS Web Soil Survey website. While sediment basin locations are typically provided by the Contractor, designers of projects being developed under watershed specific NPDES permits shall identify locations with capacity to store sediment volumes required by these permits. The location and calculations for the sediment basins shall be shown on the Project Site Plan. Additional temporary sediment and erosion control features will be added to the SWPPP by the Contractor. Submit the NOI, Project Site Plan, proposed mitigation and supplemental calculations to the Ohio EPA at least two months prior to plan package submittal to ensure that there are no delays.

11-34 January 2015


1113 Erosion Control at Bridge Ends

1113.1 General

Collect and carry bridge deck drainage that flows off the ends of the bridge in accordance to the following: A. Flow less than 0.75 ft3/s or for bridges without MSE walls – Furnish a flume, as shown on Standard

Construction Drawing DM-4.1, B. Flows greater than 0.75 ft3/s or bridges without MSE walls - Furnish an integral curb provided on the

approach slab with a standard catch basin located off the approach. Include a bridge terminal assembly at the trailing end of bridge barrier. Use a Catch Basin No. 3A, as shown on Standard Construction Drawing CB-2.2. Provide Type F conduit (707.05 Type C) for an outlet down the embankment slope and armor the outlet to prevent erosion.

C. Bridges with MSE Walls– Furnish a barrier on the approach slab with a standard inlet basin. Locate

the inlet a minimum of 25 feet beyond the limits of MSE wall soil reinforcement. Continue the barrier a minimum of 10 feet past the inlet.

1113.2 Corner Cone

Place Item 670 Slope Erosion on all bridge approach embankment corner cones, beginning at the edge of the crushed aggregate or concrete slope protection.

1114 Temporary Sediment and Erosion Control

1114.1 General

Temporary sediment and erosion control is required on all projects that have Earth Disturbing Activities as outlined in Supplemental Specification 832. A Storm Water Pollution Prevention Plan (SWPPP) is required as outlined in SS 832. Projects that may have environmental impacts to habitat or species may also be required to prepare a SWPPP as determined by the District Environmental Coordinator. The SWPPP requirements are outlined in Supplemental Specification 832. 1114.2 Cost Estimate for Temporary Sediment and Erosion Control

For all projects that require temporary sediment and erosion control furnish a dollar amount to be encumbered in the final plan package. Use the temporary sediment and erosion control estimator located in the Design Reference Resource Center to develop this amount.

1115 Post Construction Storm Water Structural Best Management Practices

1115.1 General

Post Construction Storm Water Best Management Practices (BMP) are provided for perpetual management of storm water runoff quality and quantity so that a receiving stream’s physical, chemical and biological characteristics are protected and stream functions are maintained. BMPs are required per the Ohio EPA’s NPDES permit(s), which include the Construction General permits and the Municipal Separate Storm Sewer System (MS4) permits. Two variants of the MS4 permit are possible depending on the population size of the entity seeking coverage as follows:

January 2015 11-35

Drainage Design Procedures • Small MS4 – Entities that have populations less than 100,000 within urbanized areas.

• Individual MS4 – Entities that have population in excess of 100,000. Several categories exist under

the individual MS4 permit. Local entities that administer a small or individual MS4 permit may have more restrictive language regarding selection and use of BMPs as compared to the Department. Stormwater discharge from ODOT right-of-way is permitted under the OEPA Small MS4 permit that is obtained by the Department. While the local entity cannot force the Department to use their standards, it may be possible for the Department to incorporate the needs of the local entity subject to review and approval of OHE. BMP, as described in Section 1117, shall meet permit compliance for Ohio EPA’s NPDES General Permits. For ODOT projects, any proposed alternative BMPs that are not found in Section 1117 require submittal to ODOT Central Office – Office of Hydraulic Engineering. A review and approval of the alternative BMP by ODOT Central Office – Office of Hydraulic Engineering and Ohio EPA is required. Local-Let Local Public Agency projects may use an alternative post-construction BMP criteria with Ohio EPA approval. Post-construction BMP remove pollutants from runoff (water quality treatment) and protect streams by attempting to maintain existing stream conditions or by reducing runoff volumes through structural BMP (water quantity treatment). Locate BMPs so that they are protected in accordance with Location and Design Manual, Volume 1. 1115.2 Project Thresholds for Post-Construction BMP

Post-construction BMP are required through Ohio EPA’s NPDES Construction General Permit for construction storm water discharges. The requirements to provide post-construction BMP established in the NPDES General Permit are based on Project Earth Disturbing Activities. If a NOI is not required (Section 1112), then post construction BMPs are not needed. Project Earth Disturbing Activity (EDA) is defined as any activity that exposes bare ground or an erodible material to storm water and anywhere Item 659 Seeding, Item 660 Sodding is being furnished. An area where pavement is being removed to the sub-grade is considered earth disturbing activity, except for isolated repairs. Requirements based on project EDA for non-routine maintenance projects are listed below:

Table 1115-1 Project Earth Disturbed Area Thresholds

• EDA < 1 acre - BMP and NOI not required. • EDA ≥ 1 - BMP are required. • Routine Maintenance Projects as defined in

Section 1112.2 do not require post-construction BMP.

Provide post-construction BMP for all projects exceeding the project EDA thresholds in Table 1115-1. For projects requiring post-construction BMP, the following items require evaluation:

• Need for Water Quantity and Quality Treatment vs. just Water Quality Treatment(Section 1115.3) • What is the Project Type – Redevelopment or New Construction (Section 1115.6) • If New Construction, calculate the Treatment Percent (Section 1115.7) • Project-wide or site specific implementation of BMPs to reach the required treatment (Section

1115.7) • Applicable BMP to be implemented (Section 1117)

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Drainage Design Procedures All projects, including Local Public Agency projects (ODOT-let and Local-Let) are required to provide post-construction BMP as indicated in Table 1115-1. Projects with post-construction BMP require coordination with LPAs when BMPs are required outside ODOT right-of-way. Inform the LPA of maintenance responsibilities associated with post-construction BMP. Non-contiguous portions of projects sold under one contract that do not require an NOI, as described in Section 1112.1, do not require post-construction BMP. 1115.3 Water Quality and Water Quantity Treatment

Projects exceeding the minimum thresholds in Section 1115.2 must address water quality (pollutant removal) and potentially water quantity (stream protection/volume control) post-construction BMP. BMP to address water quantity are not required for projects that meet any of the following criteria:

• Sites where one or less acre of new impervious area is created in new permanent right-of-way area being acquired for the project.

• Site is a redevelopment project within an ultra-urban setting(i.e. a downtown area or on a site where 100 percent of the project area is already impervious surface or the storm water discharge is directed into an existing storm sewer system). Redevelopment projects include construction projects on land where impervious surfaces had previously been developed and where the new land use will not increase the runoff coefficient. See Section 1115.6.

• Sites which discharge directly to a large river (>100 square mile drainage area or fourth order or greater) or to a lake and where the development area is less than 5 percent of the watershed area upstream of the development site, unless known water quality problems exist in the receiving waters. If there is a question regarding the stream classification, contact Central Office - Office of Hydraulic Engineering.

BMP that treat water quality and water quantity include:

• Extended Detention • Retention Basin • Bioretention Cell • Infiltration Trench • Infiltration Basin • Constructed Wetlands

BMP that treat only water quality include:

• Manufactured Systems • Vegetated Biofilter • Vegetated Filter Strip

Water quantity (stream protection) treatment can also be provided through the use of concrete aprons, paved depressed approach aprons, depressed inverts, and other grade control structures at stream crossings. See Section 1105 and 1106 for further information. 1115.4 Water Quality Volume

Water quality volume is directly used to determine sizing for the following BMP:

• Extended Detention • Retention Basin • Bioretention Cell • Infiltration Trench • Infiltration Basin • Constructed Wetlands

January 2015 11-37

Drainage Design Procedures The water quality volume (WQv) is used to define the amount of storm water runoff from any given storm that should be captured and treated in order to remove a majority of storm water pollutants on an average annual basis. The following equation shall be used to calculate the water quality volume:

WQv = (P*A*Cq)/12 where:

WQv = Water Quality Volume (Acre-feet) P = Precipitation (0.75 inches) A = Contributing Drainage Area (acres) Cq = 0.858i3 - 0.78i2 + 0.774i + 0.04 (see figure 1115-1) i = impervious area divided by the total area Cq = 0.9 when all drainage area is impervious.

1115.5 Water Quality Flow

Use water quality flow to determine sizing for manufactured systems. The water quality flow (WQf) is the discharge that is produced by using an intensity of 0.65 in/hr in the rational equation (section 1101.2.2). Use the entire contributing drainage for the WQf calculation. 1115.6 Project Type - Redevelopment and New Construction

1115.6.1 Redevelopment Projects

With respect to post-construction storm water BMP, redevelopment projects include projects with limited addition of impervious surface. Redevelopment projects include:

• Projects constrained entirely within right-of-way • Projects that do not add new pavement outside the existing right-of-way

While all areas within existing ODOT right-of-way may not be covered by impervious surfaces, the area within existing ODOT right-of-way is considered impervious area for the purpose of post-construction BMP design considerations. Therefore, consider all area within existing right-of-way to be impervious with a runoff coefficient of 0.90 when performing post-construction BMP calculations. 1115.6.2 New Construction Projects

All projects that do not meet the definition of redevelopment projects in Section 1115.6.1 are considered new construction projects. New construction projects allow for the reduction of treatment based on the amount of new impervious area relative to the existing impervious area of the contributing drainage area (See Section 1115.7). Consider all area within existing ODOT right-of-way to be impervious for post construction BMP calculations.

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Drainage Design Procedures 1115.7 Treatment Requirements for Projects

The amount of treatment required for a project to meet the NPDS Permit requirements is based on the earth disturbance related to the project. Area draining to a post-construction BMP will earn treatment credits equal to the amount of ODOT right-of-way area treated by the BMP. The amount of treatment may be reduced based on the amount of new impervious area relative to the existing impervious area. This weighted average for new and existing impervious area can be based on the individual drainage area tributary to each individual BMP or the entire project. However, do not combine the two approaches. The weighted value is referred to as the Treatment Percentage. Use a Treatment Percentage (T%) of 20% for redevelopment projects. Determine the Treatment Percent for New Construction projects using the following equation:

T% = [(Aix * 20)+(Ain * 100)] / (Aix+Ain)

Where,

T% = Treatment percent (Percentage)

Aix = Existing impervious area (acres)

Ain = New impervious area (acres)

• Consider all area within existing ODOT right-of-way to be impervious for post-construction BMP calculations.

Projects utilizing BMPs designed based on WQv or WQf require treatment according to one of the following:

• Provide T% treatment of the WQv or WQf for 100% of the project • Provide 100% treatment of the WQv or WQf for T% of the project earth disturbed area

Projects utilizing Vegetated Biofilters and Vegetated Filter Strips require treatment as follows:

• Provide 100% treatment of the contributing drainage area for T% of the project earth disturbed

area in a specified portion of the project. For example, a redevelopment project with 10 acres of project EDA may provide treatment through the use of a vegetated biofilter with 2 acres of contributing drainage area. The vegetated biofilter design would be based on the contributing drainage area to the ditch of 2 acres.

For all scenarios, size the BMP based on the entire contributing drainage area, offsite and on-site, to the BMP. When providing treatment based on a percentage of the project earth disturbed area, consider the following:

• Credit for water quality and water quantity treatment is only applied to the portion of the contributing drainage area within ODOT right-of-way (on-site). Any offsite contributing drainage area must be included in the BMP calculations for sizing purposes (i.e. width of ditch, etc.). However, the offsite area will not be included in the reduction of the required amount of project EDA that requires treatment.

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Example: A vegetated biofilter that has offsite contributing drainage area of one acre and on-site contributing drainage area of two acres (total drainage area of 3 acres) would result in a treatment credit of two acres. The vegetated biofilter must be sized for the total contributing drainage area of three acres. Multiple areas of a project may provide treatment to meet the total area required for compliance with the NPDES Permit. If the total area requiring treatment in this example was 4 acres, another vegetated biofilter with a minimum of two acres of on-site tributary area would be needed to meet the treatment requirements.

• For projects with multiple distinct stream crossings that do not immediately share a common

confluence downstream, provide post-construction BMP treatment proportional to the amount of Project EDA tributary to each stream.

The Treatment Percent determined above shall be used to determine treatment in the same manner as described for redevelopment projects (i.e. Treat the Treatment Percent of WQv for 100% of Project EDA, etc.).

1116 BMP Selection and Submittals

1116.1 BMP Selection

Selection of BMP shall be based on providing maximum runoff treatment while minimizing impacts to the remaining project design features, including utilities and right-of-way. In addition, each BMP option comes with unique maintenance requirements. Contact the Office of Maintenance Administration for detailed BMP maintenance information. Approval from Ohio EPA is required to use alternative BMPs not listed in Section 1117. Alternative methods will be approved or denied on a case-by-case basis if the alternative methods are demonstrated to sufficiently protect the overall integrity of the receiving streams and the watershed. For curbed roadways, total contributing drainage areas to sumps or intersections that are less than or equal to 0.25 acres as shown in figure 1116-1 do not require a BMP. Note that these exceptions are unique circumstances. Provide BMP as necessary for all other project features. For projects where the drainage sheet flows off the roadway and continues outside existing or proposed right-of-way, do not channelize flow for the sole purpose of providing a post-construction BMP. Treatment is not required for areas where sheet flow off the roadway continues to sheet flow outside ODOT right-of-way. Areas where this occurs should be documented in the post-construction BMP calculations and identified on the Project Site Plan. Design criteria for all BMP are available in Section 1117. A flow chart to determine BMP treatment requirements is provided in Figure 1115-2.

1116.2 BMP Submittals

Consider BMPs early in the design process to allow for right-of-way and utility coordination as well as evaluation with respect to waterway permitting issues. For PDP projects characterized as Paths 4 and 5, provide a description of the planned BMPs to be used for the project in the Preliminary Engineering Phase (PE). Final BMP design is required during Stage 1 plan development as identified in later tasks of the Preliminary Engineering Phase. Further refinement may be needed within the Environmental Engineering Phase. For projects categorized as Paths 1-3, it is unlikely a conceptual BMP task will be needed. Include BMPs in the Environmental Engineering Phase and potentially the Final Engineering Phase of the PDP. Submit the BMP final design during Stage 1 to ODOT Central Office – Office of Hydraulics. Include the following information:

• Estimated Project Earth Disturbed Area • Treatment Percent Calculation or justification that project is a Redevelopment Project. • BMP selected for use

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• Drainage area mapping for post-construction BMP’s that show the total contributing drainage area and the amount of contributing drainage area within ODOT right-of-way.

• Plan sheets showing locations of post-construction BMP • Calculations for each BMP (Sec. 1117) • Explanation for any area that is not treated (i.e. environmental commitment, total parcel take,

environmental resource impact, sheet flow runoff, etc.) Identify the final locations of post-construction BMP in the Project Site Plan as described in Section 1308 of Location and Design Manual, Volume 3. If applicable, provide cross-references to sheets showing post-construction BMP details on the Project Site Plan.

1117 BMP Toolbox

1117.1 Manufactured Systems

Manufactured systems consist of underground structures that treat the water quality flow (WQf) by removing particulate matter through settlement or filtration. Supplemental Specifications 895 and 995 cover the material and performance criteria for these devices. They are placed in an off-line configuration with manholes to allow for routine maintenance procedures (see figure 1117-2). Use the following procedure for design of manufactured systems: A. Determine the total contributing drainage area.

B. Calculate the WQf according to Section 1115.5.

C. If appropriate, reduce the WQf according to Section 1115.7.

D. Provide a No. 3 Manhole, With ___” Base ID and ___” Weir where flow is to be diverted to the off-line

manufactured system according to Table 1117-1 and 1117-2 and the calculated WQf.

Table 1117-1 Manufactured Systems

Type WQf (cfs)

No. 3 Manhole Base ID (inches)

611 – Type B Conduit Diameter (inches)

1 1 84 12 2 2 90 15 3 3 96 18 4 6 108 24

Reserve an area (as measured from the centerline of the No. 3 Manhole) according to Table 1117-2:

Table 1117-2 Reserved Area for Manufactured System

Type Width (ft.)

Length (ft.)

611 – Type B Total

Conduit Length (ft.)

Weir Height

(inches)

1 15 30 20 6 2 20 32 30 8 3 25 33 40 9 4 25 37 40 12

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Drainage Design Procedures E. Furnish two lengths of 611, Type B Conduit placed perpendicular to the inflowing sewer (see Table

1117-2 for the total length required).

F. Reserve an area (as measured from the centerline of the No. 3 Manhole) according to Table 1117-2. If this area is not attainable, contact Central Office – Office of Hydraulic Engineering for further guidance. Ensure the area is void of all utilities and is accessible for routine cleanout and maintenance.

For manufactured systems located along a roadway with a posted speed limit over 45 mph, locate the area for the manufactured system outside all paved areas. For manufactured systems located along a roadway with a posted speed limit of 45 mph and less, it is preferred to locate the area for the manufactured system outside paved areas. If it is not feasible to locate the area outside of the paved area, select another BMP or contact Central Office – Office of Hydraulic Engineering for further coordination. When a manufactured system is connected to a storm sewer with a depth exceeding 10 feet, contact Central Office – Office of Hydraulic Engineering. Manufactured systems are typically not suited for treatment of flows in large trunk sewers. As indicated in Table 1117-1, manufactured systems should not typically be provided on sewers that are carrying a water quality flow greater than 6 cfs. The water quality flow calculation is based on the entire contributing drainage area to the storm sewer. Add “Item 895, Manufactured Water Quality Structure, Type__” to the plans when using a manufactured system. 1117.2 Vegetation Based BMP

1117.2.1 Vegetated Filter Strip

A Vegetated Filter Strip is a BMP that filters storm water through vegetation. The Vegetated Filter Strip consists of the vegetated portion of the graded shoulder and the vegetated foreslope. The Vegetated Filter Strip must be void of gullies or concentrated flow. The water flow is characterized as overland flow throughout the grass. All areas that contribute to a slope that meets the Vegetated Filter Strip criteria in Table 1117-3 receive a treatment credit that is equal to the area of the roadway contributing to the slope and the area of the slope.

Table 1117-3 Maximum

Pavement Width (ft.)

Slope (H:V)

Filter Strip Width

(ft. minimum) 22 3:1 and flatter 15 24 3:1 and flatter 17 26 3:1 and flatter 18.5 28 3:1 and flatter 20.5 30 3:1 and flatter 22 32 3:1 and flatter 24 34 3:1 and flatter 25 46 6:1 and flatter 25

The filter strip width should be measured along the vegetated slope beginning at the vegetation and ending at the inside edge of the ditch bottom. Any area associated with concentrated flows that outlet to a vegetated filter strip should not be included in the treatment credit.

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Drainage Design Procedures Ensure underdrain outlets do not discharge to a Vegetated Filter Strip. Label the station range and location on the Project Site Plan for each Vegetated Filter Strip provided on the project. Add 6” of Item 659, Topsoil, to the vegetated portion of the shoulder and foreslope of the Vegetated Filter Strip. Add Item 670, Slope Erosion Protection, to the plans when using Vegetated Filter Strip. 1117.2.2 Vegetated Biofilter

If the Vegetated Filter Strips will not provide the required treatment, consider using a Vegetated Biofilter. A Vegetated Biofilter (VBF) is a BMP that filters storm water through vegetation and potential infiltration. The vegetated biofilter consists of the vegetated portion of the graded shoulder, vegetated slope, and vegetated ditch. The purpose of the vegetated biofilter is to allow runoff to spread out and move slowly through a shallow, flat, and vegetated conveyance. Vegetated biofilters must be void of rills, gullies, or visible erosion. When widening existing ditches, consider the following before purchasing new right-of-way:

• Provide a steeper ditch foreslope. • Provide a steeper ditch backslope. • Reducing the bench width to a minimum of 4 feet.

Consider soil conditions and safety issues prior to making any of the above changes to the existing slopes or benches. Changes to existing ditches may be regulated through waterway permits since ditches may be considered streams or wetlands. All impacts to existing streams and wetlands should be avoided or minimized to the maximum extent practicable. To determine if the proposed ditch will impact an existing stream or wetland, contact the District Environmental Coordinator. For projects utilizing the vegetated biofilter, provide a ditch width using the Enhanced Bankfull Width (EBW) or “Standard” ditch width to provide water quality treatment. Use the following steps to determine the ditch width: A. Determine Enhanced Bankfull Width (EBW):

The EBW is the width in a trapezoidal ditch for which the following criteria are met:

• The depth of flow for the water quality flow rate (WQf) is less than or equal to 4 inches. • The velocity of flow for the water quality flow rate (WQf) is less than or equal to 1 ft/sec. Use the water quality flow rate (WQf) per section 1115.5. Use Manning’s Equation to determine the depth and velocity of flow: Manning’s Equation:

𝑄𝑄 = 1.49𝑛𝑛

∗ 𝐴𝐴𝑅𝑅2 3� ∗ 𝑆𝑆1 2�

Q = flow rate (cfs) n = Manning’s Roughness Coefficient (per section 1102.3.3) A = Cross section area of flow (ft2) R = Hydraulic Radius (ft) (Area / Wetted Perimeter) S = Longitudinal Slope of ditch (ft/ft)

January 2015 11-43


There is not a direct calculation to determine EBW. Use a trial and error method to determine a width for which the depth and velocity criteria are met for the WQf, assuming open channel flow. The EBW should be whole numbers only, no half-foot increments. The minimum EBW is 4 feet. The enhanced bankfull width corresponds to the dimension of the bottom width of the trapezoidal ditch.

B. Determine “Standard” Ditch Width:

Determine the size of the trapezoidal ditch that would typically be specified for the project without accounting for water quality treatment (use typical roadway design practices). 1. If using a Radius Ditch, refer to the “b” dimension in Figure 307-2E of Location and Design

Manual, Volume 1 to determine the bottom width of the ditch. 2. If using a trapezoidal ditch, use the bottom width dimension. Ignore any rounding lengths

associated with the trapezoidal ditch. C. Determine the vegetated biofilter ditch width required for water quality treatment as described below:

1. If the EBW is less than or equal to the ”Standard” ditch width, furnish the “Standard” ditch.

2. If the EBW is greater than the “Standard” width, furnish the EBW to a maximum bottom width of ten (10) feet.

The EBW can be calculated at multiple locations along its length. This would allow the width to be reduced where there is less tributary area (i.e. the upstream area of the ditch). However, use the entire contributing drainage area to the location in the ditch being evaluated to determine the EBW. At points where concentrated offsite runoff is accepted, the EBW should be recalculated. Ensure that rock or other impervious soil layers will not prevent vegetation from being established at the invert of the flowline. If the velocity is such that rock channel protection, reinforced concrete mats, or SS836 are required, that section of the ditch cannot be used as a Vegetated Biofilter. Constriction points in the enhanced bankfull width at drive pipes or other drainage related features are acceptable. A transition back to the calculated width shall be made immediately following the constriction point. Label the station range and location on the Project Site Plan for each Vegetated Biofilter provided on the project. Add 6” of Item 659, Topsoil, to the vegetated portion of the shoulder and foreslope of the Vegetated Biofilter. Add Item 670, Ditch Erosion Protection, to the plans when using Vegetated Biofilter. 1117.3 Extended Detention

Extended detention is a method that captures storm water during rain events and slowly releases the captured volume over a period of time. The WQv is used to determine the storage volume of the detention basin. The WQv is discharged over a 48 hour time frame. Increase the WQv by 20% when sizing the BMP to allow for sedimentation to occur. Detention can be either above or below ground. Detention basins that are above ground should be used when feasible. However, when project site parameters dictate, an underground system may be considered. Due to the safety considerations and potential impacts to the drainage system, the use of extended detention BMPs requires approval from the Office of Hydraulic Engineering. Provide submittals according to Section 1116.

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Drainage Design Procedures 1117.3.1 Detention Basin

A detention basin is a dry pond that detains storm water for quality and quantity. Use the following procedure for design of the detention basin: A. Calculate the WQv per Section 1115.4.

B. Calculate the Design Check Peak Discharge per Section 1117.3.3.

C. Increase the calculated WQv by 20% to determine the required size of the detention basin.

D. Provide a forebay (settling pool located at the inlet to the basin) that is 10% of the total storage

volume (located according to Figure 1117-5), if feasible. The forebay volume is part of the required volume, and is not an additional volume requirement.

E. Provide a micropool (settling pool located at the outlet of the basin), if feasible. The micropool volume is part of the required volume, and is not an additional volume requirement.

F. Allow for 1 foot of freeboard measured from the top of embankment to the elevation needed to accommodate the storage volume.

G. Size the water quality basin (outlet structure) for proper discharge of the WQv and the weir for proper discharge of events up to the design check discharge according to Section 1117.3.1.1. Ensure that the water surface elevations created by the basin are considered in the design of the upstream drainage system.

H. Provide anti-seep collars for the outlet pipe according to Section 1117.3.1.2. The following criteria apply when designing a detention basin: A. Use side slopes of 4:1 (max)

B. Consider vehicle access to the basin for periodic maintenance.

C. Do not locate on uncompacted fill or steep slopes (2:1 or more) or where infiltrating ground water

could adversely impact slope stability.

D. Vegetate the sides of the basin with Item 670 Slope Erosion Protection.

E. Embankment work to create the impoundment will be constructed and paid for as Item 203 Embankment, Using Natural Soils, 703.16.A.

F. Furnish gravel pack protection at the outlet structure (see SCD WQ1.1).

G. Place channel protection (RCP or Tied Concrete Block Mat) at the entrance of the basin to minimize erosion and sediment resuspension.

H. Furnish a Water Quality Basin, Detention per section 1117.3.1.1

1117.3.1.1 Water Quality Basin and Weir Furnish an outlet structure that fully drains the WQv in 48 hours or more. No more than 50% of the WQv should be released from the detention basin in less than one-third the drain time. The outlet structure consists of a catch basin with a perforated riser pipe on the inlet side and a conduit on the outlet side. The perforated riser pipe is used for flow control to achieve the required discharge time. A gravel envelope surrounds the perforated riser pipe along the inlet side of the catch basin to

January 2015 11-45

Drainage Design Procedures prevent blockage of the orifice holes in the pipe. The catch basin and riser pipe are paid for as Item 611, Water Quality Basin, Detention. Details of a perforated riser pipe outlet structure can be found on standard drawing WQ1.1. The equation for a single orifice is:

where: A = Area of orifice (ft2) H = Head on orifice as measured to the centerline of the orifice (ft) C = Orifice coefficient

Table 1117-4

Orifice Coefficient Guidance C Description

0.66 Use for thin materials where the thickness is equal to or less than the orifice diameter.

0.80 Use when the material is thicker than the orifice diameter.

From CALTRANS, Storm Water Quality Handbooks, Project Planning and Design Guide, September 2002.

Furnish a weir to allow the design check discharge to bypass the structure without damage to the detention basin or embankment of the basin. The design check discharge shall be determined per 1117.3.3. Ensure that the weir is protected from erosion. A hydrograph curve for the outlet will be required to calculate the discharge time of the WQv and the design check discharge (see 1117.3.3). The discharge time should correspond to the minimum drain time of 48 hours with no more than 50% of the WQv being released from the detention basin in less than one-third the drain time. Generally, it is easier to model the outlet structure and discharge time using software such as Pond Pak or HydroCad to develop the hydrograph.

1117.3.1.2 Anti-Seep Collar Design Furnish anti-seep collars on conduits through earth fills where water is being detained. The following criteria apply to anti-seep collars: A. Furnish a minimum of 2 collars per outlet conduit. Increase the seepage length along the conduit by a

minimum of 15%. This percentage is based on the length of the pipe in the saturation zone.

B. Anti-seep collars should be placed equally within the saturation zone. Place one collar at the end of the saturation zone. In cases where the spacing limit will not allow this, place at least one collar within the saturation zone.

C. Maximum collar spacing should be 14 times the minimum projection above the pipe, but not more than 25 feet. The minimum collar spacing should be 5 times the minimum projection, but not less than 10 feet.

D. Extend the collar dimensions a minimum of 2 feet in all directions around the outside of the conduit, measured perpendicular to the conduit. Center the anti-seep collars around the conduit.

E. The top of collar shall not be less than 6 inches below, measured normal to, the finished groundline.

Q = A C. 64.4H.

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Drainage Design Procedures F. All anti-seep collars and their connections shall be watertight.

G. Minimum thickness shall be 6 inches.

H. Payment for the collar shall be Item 602 Concrete Masonry (see standard construction drawing WQ-

1.2). The design procedure for anti-seep collars is as follows:

1. Determine the length of the conduit within the saturated zone. The assumed normal saturation zone can be determined by projecting a line through the embankment, with a 4:1 (H:V) slope, from the point where the normal water elevation (10-year) meets the upstream slope to a point where it intersects the invert of the conduit. This line, referred to as the “phreatic line”, represents the upper surface of the zone of saturation within the embankment (See Figure 1117-11). The 10-year storm pool elevation is the phreatic line starting elevation.

Ls = Y(Z+4)[1+S/(0.25-S)]

where:

Ls = Length of the conduit in the saturated zone (feet) Y = Depth of the water at the spillway crest, 10-year frequency stormwater surface elevation (feet) Z = Slope of the upstream face of the embankment (Z feet horizontal to 1 foot vertical) S = Slope of the conduit (feet per foot)

2. Determine the required seepage length increase.

∆Ls = 0.15Ls

3. Choose a collar height and width that is at least 4 feet larger than the outside diameter of the

conduit (minimum projection of 2 feet from all sides of the conduit). Give collar sizes in one foot increments.

P = W – D

where:

P = Projection of collar (feet) W = Height or width of collar (feet) D = Inside diameter of conduit

4. Determine the total number of collars required. The collar size can be increased to reduce the

number of collars. Alternatively, the collar size can be decreased by providing more collars. In any case, increase the seepage length by a minimum of 15%.

No. of collars required = ∆Ls/P

1117.3.2 Underground Detention

Underground detention areas are made up of a series of conduits. They range from an oversized storm sewer to a series of conduits that are specifically used for storm water detention. Underground detention is only to be used for stream protection (water quantity treatment). Underground detention cannot be used for pollutant removal (water quality treatment) without approval from Ohio EPA. The following criteria apply when designing underground detention:

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Drainage Design Procedures A. Ensure the Hydraulic Grade Line design of the storm sewer will pass through the structure and meet

the requirements of 1104.4.2.

B. Locate access to the conduits for periodic maintenance so that traffic impacts are minimized.

C. If practical, provide pretreatment of the storm water with vegetation.

D. Payment for the conduit shall be: Item 611 ____” Conduit, Type____, for underground detention. 1117.3.3 Design Check Discharge

A design check discharge with the frequency of a 10-year event shall be used. Use the entire drainage area that contributes to the BMP to calculate the design check discharge. 1117.4 Retention Basin

A retention basin is a “wet” pond that has a minimum water surface elevation between storms that is defined as the permanent pool. Above the permanent pool is a detention pool that provides storage for 75% of the WQv and drains in 24 hours or more. The detention volume above the permanent pool is called the Extended Detention Volume (EDv). The full storage water depth is typically between 3-6 feet and the volume is less than 15 Ac-ft. The permanent pool is sized to provide storage for 75% of the WQv. A retention basin may be considered for large tributaries, but it may require a large amount of space. Use the following procedure for design of the retention basin: A. Calculate the WQv per Section 1115.4.

B. Calculate the Design Check Peak Discharge per Section 1117.3.3.

C. If feasible, provide a forebay (settling pool located at the inlet to the basin) that is 7-10% of the total

storage volume. The forebay volume is part of the required volume and is not an additional volume requirement.

D. Allow for 1 foot of freeboard measured from the top of embankment to the elevation needed to accommodate the storage volume.

E. Size the water quality basin for proper discharge of the WQv and the weir for proper discharge of events up to the design check discharge according to Section 1117.4.1. Ensure that the water surface elevations created by the basin are considered in the design of the upstream drainage system.

F. Provide anti-seep collars for the outlet pipe according to Section 1117.3.1.2. The following criteria apply when designing a retention basin: A. Place channel protection (RCP or Tied Concrete Block Mat) at the entrance of the basin to minimize

erosion and sediment resuspension.

B. Use side slopes of 4:1 (max).

C. Use a length to width ratio of at least 3:1 to prevent short-circuiting.

D. Furnish a trash rack at the outlet structure.

E. The underlying soils should be compacted to prevent infiltration of the permanent pool or an impervious liner should be used.

F. Consider vehicle access to the basin for periodic maintenance.

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G. Retention basin must be greater than 10,000 feet from a municipal airport runway.

H. Vegetate the sides of the basin with Item 670 Slope Erosion Protection.

I. Embankment work to create the impoundment will be constructed and paid for as Item 203

Embankment, Using Natural Soils, 703.16.A.

J. Furnish a Water Quality Basin, Retention per 1117.4.1. 1117.4.1 Water Quality Basin and Weir

A retention basin outlet structure is designed similar to the outlet structure for a detention basin. The difference is that the EDv (75% of the WQv) should be discharged out of the basin in 24 hours or more. No more than 50% of the EDv should be released from the detention basin in less than one-third the drain time. The outlet structures are of a similar type, except the openings will be set at a high enough elevation to maintain at least 75% of the WQv in the permanent pool (see standard construction drawing WQ-1.1). The catch basin and riser pipe is paid for as Item 611, Water Quality Basin, Retention. 1117.5 Bioretention Cell

Bioretention Cells consist of depressed low-lying areas that treat storm water through evapotranspiration and filtering through a planting soil. As the storm water passes through the soil it is filtered. An underlying perforated storm sewer or underdrain captures the treated storm water and carries it to an outlet. Extensive vegetation assists in the filtration of the storm water prior to filtering through the soil. Vegetation should consist of shrubs or grasses that are native to the area. The existing soil must be removed and replaced when constructing a bioretention cell. The bioretention planting soil (plan note WQ101) should consist of a mixture of sand, topsoil, and compost. A bioretention cell is sized to store the WQv prior to filtration. The storage volume consists of the storage area above the planting soil and void space within the planting soil. Total filtration should occur in a target drain time of 24 hours. Use the following procedure for the design of a bioretention cell, or design it using the Bioretention Design found in ODNR’s Rainwater and Land Development Manual: A. Calculate the WQv per Section 1115.4.

B. Determine the minimum surface area of the bioretention invert using the following equation:

where:

WQv = Water quality volume (Acre-feet) T = Drain time of the cell, 40 hours K = permeability of the planting soil (Use 3.3 x 10^-5 ft/sec) A = Top surface area of the trench (Ac) D = Depth of the planting soil (ft) (4.0 feet minimum)

A = WQv D.

3600 K. T. h D( ).

January 2015 11-49


h = Maximum depth of water above the cells top layer for storage (use 1 foot).

C. Ensure that a maximum depth of 1 foot measured from the riser pipe or catch basin outlet to the mulching layer surface is provided for storage.

D. Determine if the minimum surface area provides adequate volume to store the WQv. If adequate volume does not exist, increase the footprint as needed.

The following criteria apply when designing a bioretention BMP: A. Do not place where snow may be stored.

B. Furnish 10 feet or less width between 4 inch underdrain laterals.

C. Ensure that any overflow weir is protected from erosion.

D. Furnish pretreatment of the storm water via vegetation.

E. Ensure the water table or bedrock is below the invert of the bioretention area.

F. Use side slopes of 4:1 (max).

G. Use a minimum depth of 4 feet of planting soil. Provide at least 4 inches of depth deeper than the

largest root ball.

H. Furnish an organic or mulching layer at the top of the planting soil.

I. Furnish a bioretention cell as Item 203-Special - Bioretention Cell. 1117.6 Infiltration

Infiltration techniques treat storm water through the interaction of a filtering substrate that consists of soil, sand, or gravel. This technique discharges the treated storm water into the ground water rather than into surface waters. Typically, infiltration practices are only suitable when Hydrologic Soil Group (HSG) Type A soils or, in some cases, HSG Type B soils exist. Infiltration methods require an extensive investigation of the existing soils and geology to ensure success. The investigation should begin with a preliminary soil evaluation of the project site early in the design process (PDP Preliminary Engineering Phase). In-situ testing is not anticipated during the preliminary evaluation process. Use available soil and geology data found in the Soil and Water Conservation maps, United States Geological Survey (USGS), adjacent projects, or estimations from a geotechnical engineer. National Resources Conservation Service’s Web Soil Survey website may also provide soil and geology information. Material property tables for infiltration, permeability, and porosity have been provided for the preliminary evaluation (Tables 1117-4 & 1117-5). If the preliminary evaluation yields favorable results, perform a more detailed evaluation. The detailed evaluation will require a geotechnical investigation of the underlying soils and geology. Soil borings should be performed to a maximum depth of 20 feet (or refusal) with samples taken every 5 feet for laboratory testing. The number and location of soil borings should correspond with the approximate size (as determined in the preliminary evaluation) of the infiltration BMP and should be recommended by the geotechnical engineer.

11-50 January 2015

Drainage Design Procedures If the detailed evaluation yields favorable results, the ground water depth must be verified. The geotechnical engineer shall provide the seasonal high ground water depth. In some cases, observation wells may be installed and static water levels may be observed over a dry and wet season for verification. The infiltration and permeability rate of the soil shall be tested in the detailed soil evaluation at the discretion of the geotechnical engineer. In some cases, insitu testing at the proposed location of the infiltration BMP may be required. The following criteria apply to infiltration methods and must be met to be considered a feasible alternative: A. Design using the WQv as per Section 1115.

B. Do not place infiltration BMP where snow may be stored.

C. The appropriate soil type must be present:

1. Infiltration (the rate at which water enters into the soil from the surface) must be greater than 0.50

in/hr and no greater than 2.4 in/hr.

2. Soils must have less than 30% clay or 40% of clay and silt combined.

D. The invert of the structure must be at least 4 feet above the seasonal high water table and any impervious layer.

E. Infiltration techniques are not suitable on fill soil, compacted soil, or steep slopes (greater than 4:1). Consideration should be given to the long term impacts upon hillside stability if applicable.

F. Pretreatment shall be provided to remove large debris, trash and suspended sediment to extend the service life. An example of pretreatment includes providing vegetated ditches prior to flow entering the infiltration facility.

1117.6.1 Infiltration Trench

An infiltration trench is an excavated trench that has been lined with a geotextile fabric and backfilled with aggregate. The storm water is filtered through the aggregate and is stored within the pore volume of the backfill material. It is allowed to percolate through the sides and bottom of the trench. The drawdown time of the WQv is 24 hours or more. Use the following procedure for the design of an Infiltration trench: A. Based on the geotechnical data, determine if the permeability (rate of water movement in the soil) of

the surrounding soil is capable of supporting an infiltration trench.

B. Calculate the WQv per Section 1115.4.

C. Assume a width and depth for the infiltration trench. Long and deep infiltration trenches are most efficient (3 feet bottom width and 3-6 feet deep). The geometric shape of the trench is a trapezoid with sides at a 1:1 (H:V) slope due to constructability. The top width is calculated as:

Top Width = Bottom Width + (2 * Depth)

D. Determine the length of the trench based on the bottom width and depth using the following equation:

January 2015 11-51


where:

WQv = Water quality volume (see section 1115) (Acre-feet) T = Drain time through the sides of the trench, 24 hours K = permeability of the surrounding soil (ft/sec) (table 1117-4) D = Trench depth (ft) b = Bottom width of the trench (ft)

Table 1117-4 Permeability of Soil (K)

Soil Type Rate (K) (ft/sec)

Gravel 3.3x10-3 to 3.3x10-1 Sand 3.3x10-5 to 3.3x10-2 Silt 3.3x10-9 to 3.3x10-5

Clay (saturated) < 3.3x10-9 Till 3.3x10-10 to 3.3x10-6

From Urban Runoff Quality Management WEF Manual of Practice No. 23, 1998, published jointly by the WEF and

ASCE, chapter five

The following criteria apply when designing an infiltration trench:

A. Furnish a 6 inch layer of Item 601 Infiltration Basin Aggregate on the top of the trench.

B. Pretreatment using vegetation shall be provided to ensure longevity of the infiltration trench.

C. An observation well shall be provided to facilitate ground water level inspection.

D. Locate the infiltration trench at least 1,000 feet from any municipal water supply well and at least 100

feet from any private well, septic tank, or field tile drains.

E. Ensure the bottom of the trench is below the frost line (2.5 feet)

F. Furnish an infiltration trench as Item 203-Special – Infiltration Trench. 1117.6.2 Infiltration Basin

An infiltration basin is an open surface pond that uses infiltration into the ground as the release mechanism. It is designed to store the WQv. Depending on the soil permeability, it may be used to treat from 5 to 50 acres. Lower permeable soils may require an underdrain system as an additional outlet. The drawdown time of the WQv should be between 24-48 hours. Use the following procedure for the design of an infiltration basin: A. Calculate the WQv per Section 1115.4.

B. Determine the invert area of the infiltration basin using the following equation:

11-52 January 2015


A=(WQv * S.F. * 12)/(k * t)

where: A = area of invert of the basin (Acres) WQv = Water Quality Volume (see section 1115) (Acre-feet) S.F. = Safety Factor of 1.5 k = Infiltration Rate (in/hr) (table 1117-5) t = Drawdown time of 48 hours

Table 1117-5

NRCS Soil Type (from soil maps) HSG Classification Rate (k) (in/hr)

Sand A 8.0 Loamy Sand A 2.0 Sandy Loam B 1.0 Loam B 0.5 Silt Loam C 0.25 Sandy Clay Loam C 0.15 Clay Loam & Silty Clay Loam D < 0.09 Clays D < 0.05

Infiltration Rate (k) From Urban Runoff Quality Management WEF Manual of Practice No. 23, 1998, published jointly by the WEF and ASCE, chapter five

C. Use a length to width ratio of 3:1.

D. Determine the required depth of the infiltration basin using following equation:

D = WQv/A where:

A = area of invert of the basin (Acres) WQv = Water Quality Volume (Ac-ft) D = Required depth of the basin (ft)

E. Allow for 1 foot (min) freeboard above the WQv.

F. Calculate the Design Check Peak Discharge per Section 1117.3.3.

G. Furnish bypass or overflow for the design check discharge.

The following criteria apply when designing an infiltration basin: A. Use an energy dissipater at the inlet.

B. Vegetate the sides of the basin with Item 670 Slope Erosion Protection.

C. Furnish a 6 inch layer of Item 601 Infiltration Basin Aggregate on the bottom of the basin.

January 2015 11-53

Drainage Design Procedures D. Use side slopes of 4:1 (max).

E. Consider vehicle access to the basin for periodic maintenance.

F. Locate basin at least 1,000 feet from any municipal water supply well and at least 100 feet from any

private well, septic tank, or drain field.

G. Furnish 10 feet or less width between 4 inch underdrain laterals (if used in the design).

H. Do not locate the basin where infiltrating ground water may adversely impact slope stability.

I. Ensure the invert of any underdrain in the basin is below the frost line (2.5 feet).

J. Embankment work to create the impoundment will be constructed and paid for as Item 203 Embankment, Using Natural Soils, 703.16.A.

1117.7 Constructed Wetlands

Constructed Wetlands treat storm water through bio-retention. They are depressed, heavily planted areas that are designed to maintain a dry weather flow depth ranging between 0.5 to 2 feet. The surface area required for a wetland is usually quite large due to the limited allowable depth. The area is usually on the magnitude of 1% of the entire drainage area. They are designed in a similar manner as a retention basin. The wetland is sized to provide storage for the WQv for a time frame of at least 24 hours (above the permanent pool) while providing a bypass or overflow for larger design check discharge (see section 1117.3.3). The water depth should be maintained by an outlet structure capable of providing the required water depth with the provision of a one foot freeboard. The following criteria apply when designing a Constructed Wetland: A. Do not place on a steep or unstable slope or at a location, which could induce short-term or long-term

instability.

B. Constructed Wetlands must be greater than 10,000 feet from a municipal airport runway.

C. Base flow must be present to maintain the constant water depth (such as ground water).

D. Furnish a forebay that is 7% of the total required volume at a depth between 3-6 feet to settle out sediments.

E. Furnish side slopes of 4:1 (max).

F. Consider access for maintenance to the forebay and the outlet structure.

G. Vegetate the sides and bottom with grass

H. Furnish an impervious liner. Use a compacted clay bottom or a geotextile fabric to prevent infiltration of the storm water.

I. Furnish a length to width ratio of 3:1 (min) to prevent short-circuiting.

1118 Bridge Hydraulics

1118.1 General

Bridge structural design requirements are found in the Bridge Design Manual while hydraulic design criteria are governed by this manual. When submitting hydraulic design calculations, flood hazard evaluations, hydrology and hydraulic reports, and scour evaluations submit to the Office of Hydraulic Engineering.

11-54 January 2015

Drainage Design Procedures 1118.2 Hydrology and Hydraulics (H&H) Report

The H&H report is required as part of the Structure Type Study. A. A small scale area plan showing: approximate location of all stream cross sections used for the

hydraulic analysis; an accurate waterway alignment at least 500 feet each way from the structure; and the alignment of the proposed and present highways, taken from actual surveys.

B. Provide a profile along the centerline of highway so that the overflow section may be computed. This profile should extend along the approach fill to an elevation well above high water. If there are bridges or large culverts located within 1000 feet upstream or downstream from the proposed bridge, show stream cross sections including the structure and roadway profiles of the overflow sections of the structures. These may be used as a guide in establishing the waterway requirements of the proposed structure.

1118.2.1 Analysis

The H&H analysis is performed using the design year as discussed in section 1004.2 of this manual along with the 100 year and 500 year frequencies. A step backwater calculation is computed for each frequency. A one-dimensional step backwater software (example: HEC-RAS) is acceptable. In some cases a two-dimensional step backwater method may be necessary at the direction of the Department. Include the following items in the H&H analysis: A. Hydrology calculations or origin of discharge frequencies used in the analysis. Include the drainage

area in square miles. B. Electronic input and output data. If using the HEC-RAS computer program, refer to the HEC-RAS

Help Applications Guide for the “Multiple Plans” file structure. C. Plan view of stream with cross sections identified. Include enough cross sections to properly model

the existing and proposed stream as required. D. Color photographs of the upstream channel, downstream channel, and the bridge opening location. E. Computations for existing and proposed conditions.

1118.2.2 Narrative The Narrative is a written discussion the hydraulic adequacy for both the design year and 100 year frequency discharges. The narrative includes the rationale used to determine the proposed structure size and it is supported by an analysis of design alternatives. Include the following in the narrative: A. Capital costs and risk as part of the discussion. “Risk” is defined as the consequences attributable to

a flood plain encroachment.

B. A statement as to whether or not the structure is located in a flood insurance study. Identify the Flood Insurance map showing the project location, with any designated floodway information or elevations.

C. High water data from local residents and observed high water marks including their locations.

D. Approximate Flood Peak Discharge Frequency of roadway overtopping.

E. A Flood Hazard Evaluation (see 1005.2)

January 2015 11-55

Drainage Design Procedures F. Description of the bridge deck drainage. Indicate how the surface water will be collected and

discharged. Include any scupper catch basin locations.

11-56 January 2015

1100 Drainage Design Procedures – List of Figures

January 2015

Figure Subject

1101-1 Overland Flow Chart

General Notes for Figures 1101-2 and 1101-3

1101-2 Rainfall Intensity-Frequency-Duration Curves

1101-3 Rainfall Intensity Zone Map

1102-1 Capacity of Grate Catch Basin in a Sump

1102-2 Channel Features

1103-1 Nomograph for Flow in Triangular Channels

1103-2 Capacity of Curb Opening Inlets on Continuous Grade

1103-3 Capacity of Standard Catch Basin Grates in Pavement Sags - Flow Through Grate Opening

1103-4 Capacity of Inlets and Standard Catch Basins in Pavement Sags - Flow Through Curb Opening

1104-1 Type F, Broken Back Detail

1105-1 Classification of Flow in Culverts

1105-2 Corrugated Metal Pipe Sizes and "n" Values for Type A Conduits

1105-3 Example Bankfull Discharge Culvert Design

1106-1 End Treatment Grading Detail

1106-2 Box Culvert Outlet Detail

1106-3 Box Culvert Inlet Detail

1107-1 Rock Channel Protection at Culvert Storm Sewer Outlets

1112-1 Notice of Intent (NOI) Acreage Calculation Form

1115-1 Water Quality Cq

1115-2 Post-Construction BMP Treatment

1116-1 Exempt Outfalls

1117-1 Figure Deleted January 2014

1117-2 Manufactured System Detail

1117-3 Vegetated Biofilter Detail

1117-4 Figure Deleted January 2015

1117-5 Conceptual Layout for Detention Basin for Water Quality

1100 Drainage Design Procedures – List of Figures

January 2015

1117-6 Extended Detention Basin Example 1117-7 Retention Basin Example 1117-8 Bioretention Cell Example 1117-9 Infiltration Trench Example 1117-10 Infiltration Basin Example 1117-11 Anti-Seep Collars

General Notes – Figures 1101-2 through 1101-3

The Rainfall Intensity-Duration-Frequency (IDF) curves are based upon precipitation data obtained from the National Oceanic and Atmospheric Administration (NOAA) Atlas 14. The precipitation data was collected between 4/1863 to12/2000.

Rainfall depth varies across the State with more rainfall depth present in the Southwest portion of the state and gradually decreasing towards the Northeast. IDF curves were developed for 4 regions across the State to simplify hydraulic design. The regions were determined by normalizing contours created from NOAA precipitation GIS data from the 10 year, 60 minute duration.

Federal Highway Administration Hydraulic Engineering Circular No. 12 Appendix A offers a methodology for converting I-D-F data points to an equation of the general form:

i= a/(t+b)^c

Where: i = rainfall intensity (inches/hour) t = time of concentration (minutes) a = constant b = constant c = constant

Figure 1101-2 can be expressed using the above general equation utilizing the constants shown below.

Intensity Zone (Figure 1101-3) Frequency (Years)

Constant "a" Constant "b" Constant "c"

2 46.184 9.000 0.859

5 56.985 10.250 0.851

A 10 64.167 11.000 0.842

25 66.528 11.000 0.811

50 65.702 10.750 0.782

100 64.489 10.500 0.754

2 47.987 9.000 0.859

5 60.684 10.500 0.858

B 10 73.126 12.000 0.863

25 75.841 12.000 0.833

50 65.621 10.000 0.781

100 85.047 13.250 0.806

2 56.299 10.000 0.876

5 67.933 11.000 0.869

C 10 84.550 13.000 0.882

25 95.736 14.000 0.871

50 96.783 14.000 0.850

100 80.436 11.500 0.794

2 57.448 10.000 0.876

5 67.933 11.000 0.869

D 10 79.192 12.000 0.864

25 87.886 12.750 0.849

50 95.169 13.500 0.839

100 91.982 13.000 0.810

For any projects that have begun using the previous Rainfall Intensity-Duration-Frequency (IDF) curves, continue with their use through the completion of the project. The current Rainfall Intensity-Duration-Frequency (IDF) curves should be used at the start for all new projects.

Refer to General Notes ‐ Figures 1101‐2 through 1101‐3

Rainfall Intensity-Frequency-Duration Curves

Revised July 2014


1101.2.4

0

1

2

3

4

5

6

7

8

10 15 30 60 120 180

INTENSITY

(IN/H

OUR)

DURATION IN MINUTES

AREA A

2

5

10

25

50

100

Year

0

1

2

3

4

5

6

7

8

10 15 30 60 120 180

INTENSITY

(IN/H

OUR)

DURATION IN MINUTES

AREA B

2

5

10

25

50

100

Year

0

1

2

3

4

5

6

7

8

10 15 30 60 120 180

INTENSITY

(IN/H

OUR)

DURATION IN MINUTES

AREA C

2

5

10

25

50

100

Year

0

1

2

3

4

5

6

7

8

10 15 30 60 120 180

INTENSITY

(IN/H

OUR)

DURATION IN MINUTES

AREA D

2

5

10

25

50

100

Year

Revised July 2014

Rainfall Intensity-Frequency-Duration Curves1101-3

Reference Section1101.2.4

Refer to General Notes ‐ Figures 1101‐2 through 1101‐3

January 2008

Reference Section

1112

Area (acres)

Project Earth Disturbing Activities

Contractor Earth Disturbing ActivitiesField Office:

Enter 0.125 for Type A; 0.25 for Type B; or 1.00 for Type C

Batch Plant: Yes = 2.0; No = 0

Off-Project Waste / Borrow Pit:

Add 1.0 acre per 15,000 CY of waste or borrow

Miscellaneous Other Off-Project Areas:

Off-Project staging areas, stock yards, etc.

Contractor Earth Disturbing Activities Subtotal

Total Earth Disturbing Activities (add Project EDA and Contractor EDA) TOTAL

NOI Earth Disturbing Activities (see below to determine value) TOTAL

Contractor Earth Disturbing Activities:

Batch Plant - It is assumed that a typical batch plant would occupy 2 acres of ground. The designer should

investigate the location of the project relative to existing plants, facilities, etc. to estimate whether a batch plant

might be used by the Contractor. This is not needed for existing plants, it is only for plants set up for the specific

project.

NOTICE OF INTENT (NOI) ACREAGE CALCULATION FORM1112-1

Field Office - These sizes were determined with regard to size of the trailer, parking, and some stock area for

equipment and materials.

Project Earth Disturbing Activities - Enter the area of permanent earth disturbing activities directly related to project

activities. Earth disturbing activity is defined as any activity that exposes bare ground or an erodible material to

storm water and anywhere Item 659 Seeding, SS 870 Seeding, Item 660 Sodding, or SS 870 Sodding is being

furnished.

If the project is a Routine Maintenance Project, an NOI is not required. (See Section

1112)

NOI Earth Disturbing Activities - This is the combined Project and Contractor Earth Disturbed Area. Based on

project conditions and activities, some flexibility in the area calculation should be provided to avoid the possibility of

the estimated work being less than the actual work. This scenario would require submittal of an NOI for projects

originally calculated to be less than one acre during construction.

A Routine Maintenance Project consists of activities that do not change the line, grade, or hydraulic capacity of the

existing condition and has less than 5 acres of earth disturbing activities (see section 1112.2).

For projects with an estimated NOI EDA less than one acre: No NOI is required. For projects with an estimated

NOI EDA of one or more acre, but less than 4.9 acres, use 4.9 acres. For projects with an estimated NOI EDA

greater than 4.9 acres, use the sum of the Project and Contractor Earth Disturbed Areas.

Off-Project Waste / Borrow - The specified estimation is based on approximately 10 feet of depth or fill over 1

acre. The designer may choose a different value based on knowledge of the project area, bedrock elevations,

previous projects, etc. Consideration should be given for grindings, as well. (10ft. x 43560 s.f. / 27 = 16,133 c.y. ~

15,000 c.y.)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Impervious ratio

Cq

WATER QUALITY Cq1115-1

REFERENCE SECTION1115

January 2008

REFERENCE SECTIONMANUFACTURED SYSTEM DETAIL

1117-2

JULY 2011

1117

PLAN VIEW

NOT TO SCALE

OFFLINE MANUFACTURED SYSTEM

SIZED PER 1117.2

INFLOW TRUNK SEWER OUTFLOW TRUNK SEWER

MANHOLE NO. 3

W/BASE DIAMETER

PER SECTION 1117.

SOME SYSTEMS REQUIRE

TWO SMALLER MANHOLES

RATHER THAN ONE LARGE

MANHOLE.

8"

DIVERSION WEIR

RESERVED AREA FOR

A 45 DEGREE ANGLE.

LOCATED UP TO

SEWER CAN BE

OUTFLOW TRUNK

RE

SE

RV

ED

WID

TH

PE

R 1

117

Appendix A – Reproducible Forms

Form Subject LD-33 County Engineer Approval Form LD-34 Storm Sewer Computation Sheet LD-35 Ohio Drainage Design Criteria Form LD-40 Gutter Spread and Inlet Capacity Computation Sheet LD-41 Ditch Computation Sheet LD-42 Culvert Computation Sheet LD-50 No-Rise Certification LD-51 Floodplain Letter of Compliance Template

January 2015

Appendix A – Reproducible Forms

January 2015

Form LD-33

Revised July 2011

Date Submitted to District:

Date Submitted to County Engineer:

County - Route - Section:

PID:

Inlet Outlet Inlet Outlet

Comments:

Ohio Department of TransportationCounty Engineer

DateCounty Engineer's Signature

County

SkewCulvert Invert Elevation Existing Channel Elevation

Size & Type

I have reviewed and hereby approve the drainage proposed for the highway designated hereon in accordance with the provisions of the Ohio Revised Code, Section 6131.631.

Approval Form

Station

LD-33.xls

Form LD-35 Revised January 2015 PROJECT INFORMATION:

COUNTY ROUTE SECTION PID

PIPE POLICY: The Pipe Policy of _____________________ will be used for this project. ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________ (Attach a copy of the written pipe policy or furnish a link to the policy. In lieu of a written policy, documentation of locally funded construction practices may be provided) POST CONSTRUCTION BMP POLICY: The Post Construction BMP Policy of _____________________ will be used for this project. If a policy other than ODOT’s is being used, the following BMP’s are permitted: ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________ DRAINAGE WATERSHED(S): ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________ PROJECT SPECIFIC INFORMATION AFFECTING DRAINAGE: ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________

No-Rise Certification Form LD-50 Revised January 2015

This is to certify that I am a qualified licensed professional engineer in the State of Ohio. It is to

further certify that the attached analysis supports the fact that the proposed Roadway project:

_____________________________________________ in the floodway will not increase the (Name of Project)

Base Flood Elevation (100-year flood), floodway elevation, or floodway widths on

______________________________________ at published sections in the Flood Insurance (Name of Stream)

Study for ______________________________________, dated ____________________ (Name of Community)

and will not increase the Base Flood Elevations (100-year flood), floodway elevations, or

floodway widths at unpublished cross-sections in the vicinity of the proposed roadway project.

Engineer’s Name:___________________________________________

Signature:________________________________________ Date:_______________________

Phone Number:___________________ E-MAIL:__________________________________

Agency/Firm: _____________________________________________________________

Address:_____________________________________________________________________

City:____________________________ State:____________ Zip Code:_______________

ENGINEERS SEAL:

Company Letter Head or ODOT Letter Head

Date Name of Floodplain Coordinator Title County or Municipality Name Address Line 1 Address Line 2 Re: County-Route-Section (PID) Letter of Compliance Dear Name of Floodplain Coordinator: Enclosed please find the floodplain analysis for ODOT project County-Route-Section (PID). The subject roadway project encroaches upon Special Flood Hazard Area Zone A or AE within your community at the location identified in the attached report. The hydraulic calculations and No-Rise Certification Form (if Zone AE) provide the necessary documentation of compliance to all federal, state, and local floodplain standards as required. We will be proceeding forward on this project if no concerns are brought to our attention. If you need additional information please contact contact information as needed. Respectfully, Name of Registered Engineer, P.E. Title Form LD-51 Revised January 2015

Appendix B – Sample Plan Notes The Sample plan notes included in this Appendix are the most frequently used. Each note is accompanied by a “Designer Note” in an attempt to give some guidance as to when the note should be used and how to estimate quantities for some of the items where the methods for quantity calculations are not obvious. The following note categories are included: Category

Letter Prefix

Drainage Notes D Erosion Control Notes E Water Quality Notes W

January 2015

Appendix B – Sample Plan Notes

January 2015


DRAINAGE (D), EROSION CONTROL (E), & WATER QUALITY (W)

NUMBER NAME

D101 Item 611 - Catch Basin Grate

D102 Note Deleted (January 2002)

D103 Item Special - Fill and Plug Existing Conduit D104 Crossings and Connections to Existing Pipes and Utilities

D105 Pipe Connections to Corrugated Metal Structures

D106 Item 611 - Tunnel Liner Plate Structure

D107 Farm Drains D108 Item 605 - Aggregate Drains

D109 Spring Drains

D110 Unrecorded Untreated Stormwater Drainage

D111 Unrecorded Treated Stormwater Drainage D112 Item 611 - Conduit Bored or Jacked

D113 Item 611 - Conduit Under Railroad

D114 Review of Drainage Facilities D115 Unrecorded Stormwater Drainage

D116 Unrecorded Active Sanitary Sewer Connections

D117 Manholes, Catch Basins and Inlets Removed or Abandoned

D118 Item 511 Wingwalls or Headwalls for 611 Items D119 Item Special - Miscellaneous Metal

D120 Item 611 Slotted Drain

D121 Item Special - Pipe Cleanout

D122 Note Deleted (April 2009) D123 Existing Underdrains

D124 Temporary Drainage Items

E101 Seeding and Mulching E102 Sodding

W99 Post Construction Storm Water Treatment

W100 Deleted W101 Bioretention Cell(s)

W102 Infiltration Trench (or Basin)

W103 Manufactured Water Quality Structure

January 2015


D101 ITEM 611 - CATCH BASIN GRATE EXISTING CATCH BASINS SHALL BE MODIFIED BY REPLACING THE EXISTING GRATES WITH BICYCLE SAFE GRATES. QUANTITIES AND LOCATIONS ARE SHOWN IN THE PLANS AND SHALL BE PAID FOR AT THE CONTRACT PRICE FOR ITEM 611, EACH, CATCH BASIN GRATE, TYPE . Designer Note: The above note should be used on projects where existing catch basin grates are not bicycle safe. The size and type of grate to be supplied must be indicated. There may be more than one type and size on a project. If specific locations are not shown in the plan, or additional grates are to be included on a contingency basis, the following should either replace the second sentence in the note or be added to the note: THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER FOR REPLACEMENT OF EXISTING CATCH BASIN GRATES WITH BICYCLE SAFE GRATES: 611, CATCH BASIN GRATE, TYPE , EACH

D103 ITEM SPECIAL - FILL AND PLUG EXISTING CONDUIT THIS ITEM SHALL CONSIST OF THE CONSTRUCTION OF BULKHEADS IN AN EXISTING ____ IN DIAMETER CONDUIT AND FILLING THE AREA THUS SEALED OFF WITH ITEM 613, SAND OR OTHER MATERIAL APPROVED BY THE ENGINEER. BULKHEADS SHALL BE LOCATED AT THE LIMITS OF THE AREA TO BE FILLED AS INDICATED ON THE PLANS. THE BULKHEADS SHALL CONSIST OF BRICK OR CONCRETE MASONRY WITH A MINIMUM THICKNESS OF 12 INCHES. THE FILL MATERIAL SHALL BE PUMPED INTO PLACE, OR PLACED BY OTHER MEANS APPROVED BY THE ENGINEER, SO THAT, AFTER SETTLEMENT, AT LEAST 90 PERCENT OF THE CROSS-SECTIONAL AREA OF THE CONDUIT, FOR ITS ENTIRE LENGTH, SHALL BE FILLED. THE LENGTH OF FILLED AND PLUGGED CONDUIT TO BE PAID FOR SHALL BE THE ACTUAL NUMBER OF FEET (MEASURED ALONG THE CENTERLINE OF EACH CONDUIT FROM OUTER FACE TO OUTER FACE OF BULKHEADS) FILLED AND PLUGGED AS DESCRIBED ABOVE. IN LIEU OF FILLING AND PLUGGING THE EXISTING CONDUIT, THE PIPE MAY BE CRUSHED AND BACKFILLED IN ACCORDANCE WITH THE PROVISIONS OF 203, OR IT MAY BE REMOVED. THE LENGTH, MEASURED AS PROVIDED ABOVE, SHALL BE PAID FOR AT THE CONTRACT PRICE PER FOOT FOR, ITEM SPECIAL, FILL AND PLUG EXISTING CONDUIT. Designer Note: The above note should be used when it is desired to abandon an existing conduit by filling and plugging rather than more conventional methods. If the conduit is in shallow fill, the designer may delete the crush and backfill option specified in the fourth paragraph. Add pay item 202E70000 “202, Special – Fill and plug existing conduit, ___ft” to the plans.

D104 CROSSINGS AND CONNECTIONS TO EXISTING PIPES AND UTILITIES WHERE PLANS PROVIDE FOR A PROPOSED CONDUIT TO BE CONNECTED TO, OR CROSS OVER OR UNDER AN EXISTING SEWER OR UNDERGROUND UTILITY, THE CONTRACTOR SHALL LOCATE THE EXISTING PIPES OR UTILITIES BOTH AS TO LINE AND GRADE BEFORE STARTING TO LAY THE PROPOSED CONDUIT.

January 2015


IF IT IS DETERMINED THAT THE ELEVATION OF THE EXISTING CONDUIT, OR EXISTING APPURTENANCE TO BE CONNECTED, DIFFERS FROM THE PLAN ELEVATION OR RESULTS IN A CHANGE IN THE PLAN CONDUIT SLOPE, THE ENGINEER SHALL BE NOTIFIED BEFORE STARTING CONSTRUCTION OF ANY PORTION OF THE PROPOSED CONDUIT WHICH WILL BE AFFECTED BY THE VARIANCE IN THE EXISTING ELEVATIONS. IF IT IS DETERMINED THAT THE PROPOSED CONDUIT WILL INTERSECT AN EXISTING SEWER OR UNDERGROUND UTILITY IF CONSTRUCTED AS SHOWN ON THE PLAN, THE ENGINEER SHALL BE NOTIFIED BEFORE STARTING CONSTRUCTION OF ANY PORTION OF THE PROPOSED CONDUIT WHICH WOULD BE AFFECTED BY THE INTERFERENCE WITH AN EXISTING FACILITY. PAYMENT FOR ALL THE OPERATIONS DESCRIBED ABOVE SHALL BE INCLUDED IN THE CONTRACT PRICE FOR THE PERTINENT 611 CONDUIT ITEM. Designer Note: The above note is to be used when the designer is unsure of the exact location of a conduit that will require an extension or where the potential for interference between proposed and existing conduits exists.

D105

PIPE CONNECTIONS TO CORRUGATED METAL STRUCTURES CONNECTIONS OF PROPOSED LONGITUDINAL DRAINAGE TO CORRUGATED METAL STRUCTURES SHALL BE MADE BY MEANS OF A SHOP FABRICATED OR FIELD WELDED STUB ON THE STRUCTURE. THE STUB SHALL MEET THE REQUIREMENTS OF 707 AND HAVE A MINIMUM LENGTH OF 2 FEET AND A MINIMUM WALL THICKNESS OF 0.064 INCHES. THE LOCATION AND ELEVATION OF THE STUB ARE TO BE CONSIDERED APPROXIMATE AND MAY BE ADJUSTED BY THE ENGINEER TO AVOID CUTTING THROUGH JOINTS IN THE STRUCTURE. THE FIELD WELDED JOINT, IF USED, SHALL BE THOROUGHLY CLEANED AND REGALVANIZED OR OTHERWISE SUITABLY REPAIRED. WELDING SHALL MEET THE REQUIREMENTS OF 513.21. A MASONRY COLLAR, AS PER STANDARD DRAWING DM-1.1, WILL BE REQUIRED TO CONNECT THE LONGITUDINAL DRAINAGE TO THE STUB, WHEN PIPE OTHER THAN CORRUGATED METAL IS PROVIDED FOR THE LONGITUDINAL DRAINAGE. PAYMENT FOR CUTTING INTO THE STRUCTURE AND PROVIDING THE CONNECTION DESCRIBED, SHALL BE INCLUDED IN THE CONTRACT PRICE FOR ITEM 611 OR 522. Designer Note: Use the above note on all projects where connections are proposed to existing corrugated metal conduits.

D106 ITEM 611 - TUNNEL LINER PLATE STRUCTURE IN LIEU OF THE PROVISIONS OF 611.02, MATERIAL FURNISHED FOR THE LINER PLATE STRUCTURE SHALL BE AS MANUFACTURED BY: AMERICAN COMMERCIAL, INC.; COMMERCIAL INTERTECH, CORP.; CONTECH CONSTRUCTION PRODUCTS, INC.; OR AN APPROVED EQUAL. BASE METAL COMPOSITION, DEPTH AND SPAN OF THE CORRUGATIONS, AND SIZE AND SPACING OF BOLTS AND BOLT HOLES SHALL BE IN ACCORDANCE WITH THE DETAILS OF THE MANUFACTURER. INSTALLATION OF THE STRUCTURE SHALL BE IN

January 2015


ACCORDANCE WITH THE MANUFACTURER’S RECOMMENDATIONS. THE PLATE THICKNESS AND SECTION MODULUS OF THE MATERIAL FURNISHED SHALL NOT BE LESS THAN THAT INDICATED ON THE STRUCTURE DETAILS. GALVANIZING, IF SPECIFIED, SHALL BE IN ACCORDANCE WITH 707.03 AND SHALL BE DONE AFTER CORRUGATING, FORMING, AND PUNCHING THE PLATES AND BOLT HOLES. GRANULAR BEDDING WILL NOT BE REQUIRED. THE COMPLETED STRUCTURE SHALL CONFORM TO THE REQUIREMENTS OF 707. BITUMINOUS COATING, IF SPECIFIED, SHALL MEET THE REQUIREMENTS OF 707.05. Designer Note: If the space between the tunnel excavation and the tunnel liner plate is to be filled with grout, the composition of the grout and spacing of the grout couplings should be shown.

D107

FARM DRAINS ALL FARM DRAINS, WHICH ARE ENCOUNTERED DURING CONSTRUCTION, SHALL BE PROVIDED WITH UNOBSTRUCTED OUTLETS. EXISTING COLLECTORS WHICH ARE LOCATED BELOW THE ROADWAY DITCH ELEVATIONS, AND WHICH CROSS THE ROADWAY, SHALL BE REPLACED WITHIN THE (RIGHT OF WAY)( CONSTRUCTION) LIMITS BY ITEM 611 CONDUIT, TYPE B, ONE COMMERCIAL SIZE LARGER THAN THE EXISTING CONDUIT. EXISTING COLLECTORS AND ISOLATED FARM DRAINS, WHICH ARE ENCOUNTERED ABOVE THE ELEVATION OF ROADWAY DITCHES, SHALL BE OUTLETTED INTO THE ROADWAY DITCH BY 611 TYPE F CONDUIT. THE OPTIMUM OUTLET ELEVATION SHALL BE ONE FOOT ABOVE THE FLOWLINE ELEVATION OF THE DITCH. LATERAL FIELD TILES WHICH CROSS THE ROADWAY SHALL BE INTERCEPTED BY 611, TYPE E CONDUIT, AND CARRIED IN A LONGITUDINAL DIRECTION TO AN ADEQUATE OUTLET OR ROADWAY CROSSING. THE LOCATION, TYPE, SIZE AND GRADE OF REPLACEMENTS SHALL BE DETERMINED BY THE ENGINEER AND PAYMENT SHALL BE MADE ON FINAL MEASUREMENTS. EROSION CONTROL PADS AND ANIMAL GUARDS SHALL BE PROVIDED AT THE OUTLET END OF ALL FARM DRAINS AS PER STANDARD CONSTRUCTION DRAWING DM-1.1, EXCEPT WHEN THEY OUTLET INTO A DRAINAGE STRUCTURE. PAYMENT FOR THE EROSION CONTROL PADS AND ANIMAL GUARDS AND ANY NECESSARY BENDS OR BRANCHES SHALL BE INCLUDED FOR PAYMENT IN THE PERTINENT CONDUIT ITEMS. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR THE WORK NOTED ABOVE: 611 “ CONDUIT, TYPE B ________ FT 611 “ CONDUIT, TYPE E ________ FT 611 “ CONDUIT, TYPE F ________ FT 601 ROCK CHANNEL PROTECTION TYPE C WITH FILTER ________ CU. YD Designer Note: The above note is to be used where excavation may conflict with existing farm drains. Use of a lateral field interceptor tile located on a temporary easement outside the limited access right of way may be appropriate on limited access facilities.

January 2015


D108 ITEM 605 - AGGREGATE DRAINS AGGREGATE DRAINS SHALL BE PLACED AT 50 FOOT INTERVALS ON EACH SIDE OF NORMAL CROWNED SECTIONS, STAGGERED SO THAT EACH DRAIN IS 25 FEET FROM THE ADJACENT DRAIN ON THE OPPOSITE SIDE, AND AT 25 FOOT INTERVALS ON THE LOW SIDE ONLY OF SUPERELEVATED SECTIONS. AN AGGREGATE DRAIN SHALL BE PLACED AT THE LOW POINT OF EACH SAG VERTICAL CURVE. Designer Note: This note should be used on long projects with aggregate drains. On short projects, such as bridge replacements, the station and side for aggregate drain placement should be specified in the plans.

D109 SPRING DRAINS THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN CARRIED TO THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER FOR DRAINING ANY SPRINGS SHOWN IN THE PLAN OR ENCOUNTERED DURING CONSTRUCTION. THE FOLLOWING TYPES OF PIPES MAY BE USED: 707.33, 707.41, 707.42 or 707.45 PERFORATED PER 707.31. SPRING DRAINS SHALL BE CONSTRUCTED AS SHOWN ON STANDARD CONSTRUCTION DRAWING DM-1.1 AND PAID FOR AT THE CONTRACT PRICE FOR: 605, 6" UNCLASSIFIED PIPE UNDERDRAINS FOR SPRINGS ________ FT. 605, AGGREGATE DRAINS FOR SPRINGS ________ FT. 611, PRECAST REINFORCED CONCRETE OUTLET ________ EACH Designer Note: This note should be used only where springs are present in the project area and/or the project area is known to have spring activity. In addition to quantities required to drain springs located by field work, estimated contingency quantities should be included for draining springs encountered during construction.

D110

UNRECORDED UNTREATED NON-STORMWATER DRAINAGE FURNISH NO CONTINUANCE FOR ANY UNRECORDED UNTREATED NON-STORMWATER DRAINAGE SUCH AS UNTREATED SEPTIC, UNTREATED WASTEWATER, UNTREATED CURTAIN/GRADIENT DRAINS, AND UNTREATED FOUNDATION FLOOR DRAINS DISTURBED BY THE WORK. PLUG ANY UNRECORDED UNTREATED NON-STORMWATER DRAINAGE WITH CONCRETE AT THE RIGHT OF WAY LINE. PAYMENT FOR PLUGGING SHALL BE INCLUDED IN THE CONTRACT PRICE FOR THE PERTINENT 202 OR 203 ITEM. Designer Note: This note is to be used only if there is a possibility that during construction there may be a need for additional plugging of untreated non-stormwater drainage. The Designer shall make a complete investigation for the presence of untreated non-stormwater drainage. List quantities required for all untreated non-stormwater drainage at the specific locations on the Plan & Profile sheets. All located untreated non-stormwater drainage is required to be plugged with concrete at the right-of-way line.

January 2015


D111 UNRECORDED TREATED NON-STORMWATER DRAINAGE FURNISH A CONTINUANCE FOR ALL UNRECORDED TREATED NON-STORMWATER DRAINAGE, SUCH AS TREATED SEPTIC, TREATED WASTEWATER, TREATED CURTAIN/GRADIENT DRAINS, AND TREATED FOUNDATION FLOOR DRAINS DISTURBED BY THE WORK. FURNISH EITHER AN OPEN CONTINUANCE OR AN UNOBSTRUCTED CONTINUANCE BY CONNECTING A CONDUIT THROUGH THE CURB OR INTO A DRAINAGE STRUCTURE. THE LOCATION, TYPE, SIZE AND GRADE OF THE NEEDED CONDUIT TO REPLACE OR EXTEND AN EXISTING DRAIN WILL BE DETERMINED BY THE ENGINEER. ALL SUCH CONTINUANCE REQUIRES A RIGHT OF WAY USE PERMIT. A CONTINUANCE MAY ALSO REQUIRE A NPDES PERMIT FROM THE OHIO ENVIRONMENTAL PROTECTION AGENCY. REPORT ALL CONTINUANCE TO THE LOCAL HEALTH DEPARTMENT. WHERE MAKING A CONNECTION INTO A HIGHWAY DRAINAGE CONDUIT, AN INSPECTION WELL SHALL BE PROVIDED IN ACCORDANCE WITH STANDARD CONSTRUCTION DRAWING DM-3.1. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER IN MAKING THE ABOVE CONTINUANCE: 611, ______ “ CONDUIT, TYPE C ________ FT. 611, INSPECTION WELL ________ EACH Designer Note: This note is to be used only if there is a possibility that during construction there may be a need for additional continuance of treated non-stormwater drainage. The Designer shall make a complete investigation for the presence of treated non-stormwater drainage. List quantities required for all treated non-stormwater drainage at the specific locations on the Plan & Profile sheets. All located treated non-stormwater drainage is required to have a right of way use permit. If any such located treated non-stormwater drainage do not have a right of way use permit then notice of such is required to be sent to the appropriate parities. All treated non-stormwater drainage may also require a NPDES permit from the Ohio Environmental Protection Agency. Report all continuance to the local health department.

D112 ITEM 611 - CONDUIT BORED OR JACKED WHERE IT IS SPECIFIED THAT A CONDUIT BE INSTALLED BY THE METHOD OF BORING OR JACKING, NO TRENCH EXCAVATION SHALL BE CLOSER THAN _____ FEET TO THE (EDGE OF PAVEMENT) (NEAREST RAIL). PROVIDE A STEEL CASING PIPE CONFORMING TO 748.06 HAVING JOINTS WITH A CIRCUMFERENCIAL FULLY PENETRATING B-U4B WELD THAT IS PERFORMED BY AN ODOT APPROVED FIELD WELDER. THE INSTALLED CASING PIPE IS THE STORM WATER CONVEYANCE CARRIER UNLESS OTHERWISE SPECIFIED IN THE PLANS. HYDROSTATIC TESTING IS NOT REQUIRED FOR THE CASING PIPE. Designer Note: The pay item in the General Summary shall read, 611 Conduit Bored or Jacked, “, Type , Ft. Where a conduit is installed by this method under a railroad, the designer should coordinate with the Rail Company to determine the allowable distance from the nearest rail and add note D113 to the plans. Specify a concrete masonry collar between the casing pipe and adjacent conduit material if the casing pipe is used as the final carrier pipe.

January 2015


D113 ITEM 611 – CONDUIT UNDER RAILROAD THE STATE SHALL PAY TO THE RAIL COMPANY ALL COSTS FOR WATCHMEN OR FLAGGERS DEEMED NECESSARY BY THE RAIL COMPANY, OR OCCASIONED BY THE OPERATIONS OF THE CONTRACTOR, OR ANY SUB-CONTRACTOR, IN CARRYING FORWARD THE INSTALLATION OF PIPE OR CONDUIT UNDER THE RAILROAD PER THE PLAN. THE COSTS FOR WATCHMEN OR FLAGGERS REQUIRED BY AN ALTERNATE METHOD OF INSTALLATION SHALL BE PAID TO THE RAIL COMPANY BY THE CONTRACTOR. THE COSTS FOR WATCHMEN OR FLAGGERS OCCASIONED BY THE NEGLIGENCE OF THE CONTRACTOR, OR ANY SUB-CONTRACTOR, IN CONNECTION WITH THE INSTALLATION OF THE PIPE OR CONDUIT SHALL BE PAID BY THE CONTRACTOR. TRACK SUPPORTS REQUIRED BY THE RAIL COMPANY IN CONNECTION WITH THE INSTALLATION OF THE PIPE OR CONDUIT PER THE PLAN SHALL BE INCLUDED IN THE COMPANY FORCE ACCOUNT WORK AND PAID BY THE STATE. THE COST OF ANY TRACK SUPPORTS REQUIRED BY AN ALTERNATE METHOD OF INSTALLATION OF THE PIPE OR CONDUIT SHALL BE SHALL BE PAID TO THE RAIL COMPANY BY THE CONTRACTOR. THE CONTRACTOR SHALL SECURE APPROVAL OF HIS OPERATIONS FROM THE STATE AND THE RAIL COMPANY. THE RAIL COMPANY WILL PERFORM AN ENGINEERING REVIEW OF METHODS OF OPERATIONS AND ENGINEERING SUPERVISION OF CONSTRUCITON WITHOUT COST TO THE CONTRACTOR. PRIOR TO BIDDING, THE CONTRACTOR SHALL COORDINATE WITH THE RAIL COMPANY TO AGREE UPON THE REQUIREMENTS OF WATCHMEN AND FLAGGERS TO PROTECT RAILROAD TRAFFIC DURING THE CONTRACTOR’S OPERATIONS. THE CONTRACTOR SHALL EXECUTE A BOND IN FAVOR OF BOTH THE STATE AND THE COMPANY AS REQUIRED BY SECTION 5525.16 OF THE REVISED CODE OF OHIO. THE CONTRACTOR SHALL CO-OPERATE WITH THE RAILROAD OFFICIALS CONCERNING WORK ADJACENT TO RAILROAD TRACKS, IN ORDER TO AVOID DELAY TO, OR INTERFERENCE WITH RAILROAD TRAFFIC, AND SHALL NOTIFY THE COMPANY ______ HOURS IN ADVANCE OF CONSTRUCTION OPERATIONS. Designer Note: Provide this note when placing pipe culverts, sewers, or water lines under railroads. Through coordination with the railroad complete the ____hours that the railroad would like to be notified by.

D114

REVIEW OF DRAINAGE FACILITIES BEFORE ANY WORK IS STARTED ON THE PROJECT AND AGAIN BEFORE FINAL ACCEPTANCE BY THE STATE, REPRESENTATIVES OF THE STATE AND THE CONTRACTOR, ALONG WITH LOCAL REPRESENTATIVES, SHALL MAKE AN INSPECTION OF ALL EXISTING SEWERS WHICH ARE TO REMAIN IN SERVICE AND WHICH MAY BE AFFECTED BY THE WORK. THE CONDITION OF THE EXISTING CONDUITS AND THEIR APPURTENANCE SHALL BE DETERMINED FROM FIELD OBSERVATIONS. RECORDS OF THE INSPECTION SHALL BE KEPT IN WRITING BY THE STATE. ALL NEW CONDUITS, INLETS, CATCH BASINS, AND MANHOLES CONSTRUCTED AS A PART OF THE PROJECT SHALL BE FREE OF ALL FOREIGN MATTER AND IN A CLEAN CONDITION BEFORE THE PROJECT WILL BE ACCEPTED BY THE STATE.

January 2015


ALL EXISTING SEWERS INSPECTED INITIALLY BY THE ABOVE MENTIONED PARTIES SHALL BE MAINTAINED AND LEFT IN A CONDITION REASONABLY COMPARABLE TO THAT DETERMINED BY THE ORIGINAL INSPECTION. ANY CHANGE IN THE CONDITION RESULTING FROM THE CONTRACTOR’S OPERATIONS SHALL BE CORRECTED BY THE CONTRACTOR TO THE SATISFACTION OF THE ENGINEER. PAYMENT FOR ALL OPERATIONS DESCRIBED ABOVE SHALL BE INCLUDED IN THE CONTRACT PRICE FOR THE PERTINENT 611 CONDUIT ITEMS. Designer Note: This note is to be used on projects where existing drainage facilities are to remain in service.

D115

UNRECORDED STORM WATER DRAINAGE FURNISH A CONTINUANCE FOR ALL UNRECORDED STORM WATER DRAINAGE, SUCH AS ROOF DRAINS, FOOTER DRAINS, OR YARD DRAINS, DISTURBED BY THE WORK. FURNISH EITHER AN OPEN CONTINUANCE OR AN UNOBSTRUCTED CONTINUANCE BY CONNECTING A CONDUIT THROUGH THE CURB OR INTO A DRAINAGE STRUCTURE. THE LOCATION, TYPE, SIZE AND GRADE OF THE NEEDED CONDUIT TO REPLACE OR EXTEND AN EXISTING DRAIN WILL BE DETERMINED BY THE ENGINEER. ALL SUCH CONTINUANCE REQUIRES A RIGHT OF WAY USE PERMIT. THE FOLLOWING CONDUIT TYPES MAY BE USED: 707.33, 707.41 NON-PERFORATED, 707.42, 707.43, 707.45, 707.46, 707.47, 707.51, 707.52 SDR35. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER FOR THE WORK NOTED ABOVE: 611, ______ “ CONDUIT, TYPE B, FOR DRAINAGE CONNECTION ________ FT. 611, ______ “ CONDUIT, TYPE C, FOR DRAINAGE CONNECTION ________ FT. 611, ______ “ CONDUIT, TYPE E, FOR DRAINAGE CONNECTION ________ FT. 611, ______“ CONDUIT, TYPE F, FOR DRAINAGE CONNECTION ________ FT. Designer Note: This note is to be used only if there is a possibility that during construction there may be a need for additional continuance of storm water drainage from residential or commercial property. The designer shall make a complete investigation for the presence of existing storm water drainage from residential and commercial property. List quantities required for all located storm water drainage from residential and commercial property at the specific locations on the Plan & Profile sheets. All located storm water drainage from residential or commercial property is required to have a right of way use permit. If any such located storm water drainage from residential or commercial property do not have a right of way use permit then notice of such is required to be sent to the appropriate parities. Designer Note: This note is to be used only if there is a possibility that during construction there may be a need for additional residential and commercial connections. The designer shall make a complete investigation for the presence of existing residential and commercial drainage connections and quantities should be listed at the specific locations on the Plan & Profile sheets.

January 2015


D116 UNRECORDED ACTIVE SANITARY SEWER CONNECTIONS FURNISH A CONTINUANCE FOR ALL UNRECORDED ACTIVE SANITARY SEWER CONNECTIONS SUCH AS SANITARY, WASTEWATER, CURTAIN/GRADIENT DRAINS, AND FOUNDATION FLOOR DRAINS DISTURBED BY THE WORK. FURNISH AN UNOBSTRUCTED CONTINUANCE OF THE UNRECORDED ACTIVE SANITARY SEWER CONNECTIONS TO THE SATISFACTION OF THE ENGINEER. ALL SUCH CONTINUANCE REQUIRES A RIGHT OF WAY USE PERMIT. ALL SANITARY AND SANITARY WASTEWATER CONTINUANCE MAY ALSO REQUIRE A NPDES PERMIT FROM THE OHIO ENVIRONMENTAL PROTECTION AGENCY. REPORT ALL CONTINUANCE TO THE LOCAL HEALTH DEPARTMENT. THE FOLLOWING CONDUIT TYPES MAY BE USED: 707.42, 707.43, 707.44, 707.45, 707.46, 707.47, 707.51, 707.52 SDR35, 706.01, 706.02, OR 706.08 WITH JOINTS AS PER 706.11 OR 706.12. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER FOR THE WORK NOTED ABOVE: 611, ______ “ CONDUIT, TYPE B, FOR SANITARY ______ FT. 611, ______ “ CONDUIT, TYPE C, FOR SANITARY ______ FT. Designer Note: This note is to be used only if there is a possibility that during construction there may be a need for additional continuance of active sanitary sewer connections. The Designer shall make a complete investigation for the presence of active sanitary sewer connections. List quantities required for all active sanitary sewer connections at the specific locations on the Plan & Profile sheets. All located active sanitary sewer connections is required to have a right of way use permit. If any such located active sanitary sewer connections do not have a right of way use permit then notice of such is required to be sent to the appropriate parities. All sanitary and sanitary wastewater active sanitary sewer connections may also require a NPDES permit from the Ohio Environmental Protection Agency. Report all continuance to the local health department.

D117 MANHOLES, CATCH BASINS AND INLETS REMOVED OR ABANDONED ALL CASTINGS SHALL BE CAREFULLY REMOVED AND STORED WITHIN THE RIGHT OF WAY FOR SALVAGE BY (STATE) (CITY) (VILLAGE) (COUNTY) FORCES. PAYMENT FOR ALL OF THE ABOVE SHALL BE INCLUDED IN THE CONTRACT PRICE FOR THE PERTINENT 202 ITEM. Designer Note: This note shall only be used where it has been determined that the owner desires to retain the existing castings.

January 2015


D118

ITEM 511 WINGWALLS OR HEADWALLS FOR 611 ITEMS FOR ITEMS 706.05, 706.051, 706.052 AND 706.053 WITH A CAST-IN-PLACE WINGWALL OR HEADWALL A PRECAST ALTERNATIVE MAY BE FURNISHED PER 602.03. THE PRECAST ALTERNATIVE WILL MEET THE CAST-IN-PLACE STRUCTURAL DESIGN LOADINGS, DESIGN HEIGHT, AND DESIGN LENGTH DIMENSIONS. FULL COMPENSATION FOR THE PRECAST WINGWALL OR HEADWALL IS THE NUMBER OF CUBIC YARDS OF ITEM 511 AND POUNDS OF ITEM 509 FOR THE CORRESPONDING CAST-IN-PLACE STRUCTURE. Design Note: Include this note on all plans that have item 611, three-sided flat top, arch top, arches or box culverts that have an item 511 cast-in-place wingwall or headwall.

D119

ITEM SPECIAL- MISCELLANEOUS METAL EXISTING CASTINGS MAY PROVE TO BE UNSUITABLE FOR REUSE, AS DETERMINED BY THE ENGINEER. IT SHALL BE THE CONTRACTOR’S RESPONSIBILITY TO PROVIDE THE CASTINGS OF THE REQUIRED TYPE, SIZE AND STRENGTH (HEAVY OR LIGHT DUTY) FOR THE PARTICULAR STRUCTURE IN QUESTION. ALL MATERIAL SHALL MEET ITEM 611 OF THE SPECIFICATIONS AND SHALL HAVE THE PRIOR APPROVAL OF THE ENGINEER. THE FOLLOWING ESTIMATED QUANTITY HAS BEEN CARRIED TO THE GENERAL SUMMARY FOR USE AS DIRECTED BY THE ENGINEER. SPECIAL, MISCELLANEOUS METAL _____ POUNDS THE CONTRACTOR IS CAUTIONED TO USE EXTREME CARE IN THE REMOVAL, STORAGE AND REPLACEMENT OF ALL EXISTING CASTINGS. CASTINGS DAMAGED BY THE NEGLIGENCE OF THE CONTRACTOR, AS DETERMINED BY THE ENGINEER, SHALL BE REPLACED WITH THE PROPER NEW CASTINGS AT THE EXPENSE OF THE CONTRACTOR. Designer Note: Use this note if existing castings are to be reused and which may be unsuitable.

D120 ITEM 611 - ( )”, SLOTTED DRAIN, TYPE ( ) THIS ITEM SHALL CONSIST OF ____ INCH DIAMETER SLOTTED DRAIN ALUMINUM COATED STEEL CONDUIT 707.01 WITH 6 INCH TRAPEZOIDAL GALVANIZED SOLID BAR GRATE AS APPROVED BY THE ENGINEER. ALL COSTS FOR LABOR AND MATERIALS, INCLUDING TYPE 2 BEDDING, AND BACKFILLING AS DETAILED ON STANDARD CONSTRUCTION DRAWING DM-1.3 SHALL BE INCLUDED IN THE PRICE BID PER FOOT FOR ITEM 611 - ____ “ SLOTTED DRAIN,TYPE ____ . Designer Note: This plan note should be used in conjunction with Standard Construction Drawing DM-1.3. Outlet slotted drain pipe into a catch basin.

D121 ITEM SPECIAL - PIPE CLEANOUT THIS WORK SHALL CONSIST OF REMOVING SEDIMENT AND DEBRIS FROM THE EXISTING DRAINAGE CONDUITS SPECIFIED IN THE PLANS. ALL MATERIAL REMOVED SHALL BE DISPOSED OF AS PER 105.16 AND 105.17. ALL SEWERS SHALL BE CLEANED OUT TO THE SATISFACTION OF THE ENGINEER.

January 2015


CLEANOUT OF THE PIPE SHALL BE PAID FOR AT THE UNIT PRICE BID FOR ITEM SPECIAL - PIPE CLEANOUT. THIS PRICE SHALL INCLUDE THE COST FOR MATERIAL, EQUIPMENT, LABOR, AND ALL INCIDENTALS REQUIRED TO COMPLETE THE CLEANOUT. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR THE ABOVE NOTED WORK: SPECIAL, PIPE CLEANOUT, 24” AND UNDER ________ FT. SPECIAL, PIPE CLEANOUT, 27” TO 48” ________ FT. SPECIAL, PIPE CLEANOUT, OVER 48” ________ FT. Designer Note: This item may not be eligible for federal participation.

D123

EXISTING SUBSURFACE DRAINAGE PROVIDE UNOBSTRUCTED OUTLETS FOR ALL EXISTING UNDERDRAINS OR AGGREGATE DRAINS ENCOUNTERED DURING CONSTRUCTION. PROVIDE AN OUTLET PER STANDARD CONSTRUCTION DRAWING DM-1.1 FOR ALL UNDERDRAINS THAT OUTLET TO A SLOPE. UNDERDRAINS THAT CAN BE CONNECTED TO THE NEW OR EXISTING UNDERDRAINS AT THE END OF THE PROJECT LIMITS AS WELL AS ALL NECESSARY BENDS OR BRANCHES REQUIRED FOR CONNECTION ARE INCLUDED IN THE BASIS OF PAYMENT FOR UNCLASSIFIED PIPE UNDERDRAINS. THE FOLLOWING ESTIMATED QUANTITIES HAVE BEEN INCLUDED IN THE GENERAL SUMMARY FOR THE WORK NOTED ABOVE: 601, TIED CONCRETE BLOCK MAT, TYPE 1 __________SQ. YD. 605, AGGREGATE DRAINS __________FT. 611__________” CONDUIT, TYPE F __________FT. 611, PRECAST REINFORCED CONCRETE OUTLET __________EACH 605__________” UNCLASSIFIED PIPE UNDERDRAINS __________FT. Designer Note: The note is to be used on projects if there are existing underdrains or aggregate drains within the project limits that are to remain. The designer shall make a complete investigation for the presence of existing underdrain outlet locations or potential conflict areas within the project limits and show them on the plan view sheets.

D124 TEMPORARY DRAINAGE ITEMS

TEMPORARY DRAINAGE ITEMS LABELED ON THE MAINTENANCE OF TRAFFIC PLAN ARE ITEMIZED ON THE MOT PLANS. PAYMENT FOR THE TEMPORARY DRAINAGE ITEMS ARE ITEMIZED AND CARRIED TO THE GENERAL SUMMARY. Designer Note: Provide this note when temporary drainage items are required in accordance to section 1010 of the L&D. Furnish drainage items for each phase of the maintenance of traffic operations. Removal items may be required between individual phases. Utilize drainage structures furnished for final drainage design where feasible.

January 2015


E101

SEEDING AND MULCHING THE FOLLOWING QUANTITIES ARE PROVIDED TO PROMOTE GROWTH AND CARE OF PERMANENT SEEDED AREAS: 659, SOIL ANALYSIS TEST ____ EACH 659, TOPSOIL ____ CU. YD. 659, SEEDING AND MULCHING ____ SQ. YD. 659, REPAIR SEEDING AND MULCHING ____ SQ. YD. 659, INTER-SEEDING ____ SQ. YD. 659, COMMERCIAL FERTILIZER ____ TON 659, LIME ____ ACRES 659, WATER ____ M. GAL. 659, MOWING ____ M. SQ. FT. SEEDING AND MULCHING SHALL BE APPLIED TO ALL AREAS OF EXPOSED SOIL BETWEEN THE RIGHT-OF-WAY LINES, AND WITHIN THE CONSTRUCTION LIMITS FOR AREAS OUTSIDE THE RIGHT-OF-WAY LINES COVERED BY WORK AGREEMENT OR SLOPE EASEMENT. QUANTITY CALCULATIONS FOR SEEDING AND MULCHING ARE BASED ON THESE LIMITS. Designer Note: The above quantities should be used on all projects that require grading work. The following is a basic guideline for estimating quantities for the above items. These quantities may be omitted from the note if they are itemized elsewhere in the plan. Calculations for all items should be shown in the plans. 659, Soil Analysis Test (Each) Soil Analysis Tests are used to field adjust the rate of Lime based on soil conditions. A. Soil Analysis Test is not specified.

1. The standard rate for Lime will be used without adjustment.

B. Soil Analysis Test is specified. If specified, minimum of two tests.

1. If no Topsoil to be placed - One test per 10 Acres (one test per 48400 Sq. Yd.) of permanent seeded area and sodded area.

2. If placing Topsoil - One test per 10000 Cu. Yds. of Topsoil.

659, Topsoil (Cu. Yd.) 111 Cu. Yds. per 1000 Sq. Yd. of permanent seeded area. Topsoil is optional. However, it is recommended, especially for projects involving A4 silty materials, granular embankment or granular materials due to severe erosion problems.

659, Seeding and Mulching (Sq. Yd.)

This quantity is usually calculated by the end width method using the cross sections. On short projects, seeding quantities may be determined by other methods. For example, the area for seeding may be estimated by calculating an area per Plan & Profile sheet determined by multiplying an average width (based on construction limits or right-of -way lines) by the distance on each sheet, and then deducting for paved surface areas. A deduction should be taken for 660 and 670 items. 659, Repair Seeding and Mulching (Sq. Yd.) 5 % of the permanent seeding and mulching area.

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659, Inter-seeding (Sq. Yd.) 5% of the permanent seeding and mulching area.

659, Commercial Fertilizer (Ton)

30 pounds per 1000 Sq. Ft. ( one Ton per 7410 Sq. Yd.) of permanent seeded area. This rate includes 20 pounds per 1000 Sq. Ft. for the first application and 10 pounds per 1000 Sq. Ft. for the second application. If Inter-seeding is provided, use an additional 20 pounds per 1000 Sq. Ft. of commercial fertilizer for the Inter-seeding area. 659 Lime (Acre) Apply over permanent seeded area. 659, Water (M. Gal.) Two applications each at 300 Gallons per 1000 Sq. Ft. (0.0027 M Gallons per Sq. Yd.) of permanent seeded area. The above rate is for a single application. If Inter-seeding is provided, use an additional 300 Gallons per 1000 Sq. Ft. of water for the Inter-seeded area. 659, Mowing (M. Sq. Ft.)

25 % of the permanent seeded area for projects expected to last more than one construction season.

E102

SODDING THE FOLLOWING QUANTITIES ARE PROVIDED TO PROMOTE GROWTH AND CARE OF PERMANENT SODDED AREAS. 659, SOIL ANALYSIS TEST ____ EACH 659, TOPSOIL ____ CU. YD. 659, COMMERCIAL FERTILIZER ____ TON 659, LIME ____ ACRE 659, WATER ____ M. GAL. 660, SODDING, UNSTAKED, STAKED, REINFORCED ____ SQ. YD. Designer Note: The above quantities should be used on all projects that have pay item(s) for permanent sodding. The following is a basic guideline for estimating quantities for the above items. These quantities may be omitted from the note if they are itemized elsewhere in the plan. Calculations for all items should be shown in the plans. 659, Soil Analysis Test (Each) Soil Analysis Tests are used to field adjust the rate of Lime based on soil conditions. C. Soil Analysis Test is not specified.

1. The standard rate for Lime will be used without adjustment.

D. Soil Analysis Test is specified. If specified, minimum of two tests.

1. If no Topsoil to be placed - One test per 10 Acres (one test per 48400 Sq. Yd.) of permanent sodded area.

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2. If placing Topsoil - One test per 10000 Cu. Yds. of Topsoil.

659, Topsoil (Cu. Yd.) 111 Cu. Yds. per 1000 Sq. Yd. of permanent sodded area. Topsoil is optional. However, it is recommended, especially for projects involving A4 silty materials, granular embankment or granular materials due to severe erosion problems. 659, Commercial Fertilizer (Ton) 30 pounds per 1000 Sq. Ft. (one Ton per 7410 Sq. Yd.) of permanent sodded area. This rate includes 20 pounds per 1000 Sq. Ft. for the first application and 10 pounds per 1000 Sq. Ft. for the second application. 659, Lime (Acre) Apply over permanent sodded area. 659, Water (M. Gal.) 1 application every 7 days for an additional 2 months beyond the requirements of 660.09. The rate shall be 300 gallons per 1000 Sq. Ft. (0.0027 M. Gallons per Sq. Yd.) of permanent sodded area. 660, Sodding (Sq. Yd.) This is the actual number of Sq. Yds. of permanent sodded area.

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W99 POST CONSTRUCTION STORM WATER TREATMENT THIS PLAN UTILIZES STRUCTURAL BEST MANAGEMENT PRACTICES (BMP’S) FOR POST CONSTRUCTION STORM WATER TREATMENT. Designer Note: This plan note shall be used on all projects that have post construction storm water management BMP’s. The note shall be followed by the below notes if applicable.

W101 BIORETENTION CELL(S)

CONSTRUCT THE BIORETENTION CELL(S) AFTER ALL CONTRIBUTING DRAINAGE AREAS ARE STABILIZED AS SHOWN ON THE CONTRACT PLANS AND TO THE SATISFACTION OF THE ENGINEER. DO NOT USE THE COMPLETED BIORETENTION CELL(S) AS TEMPORARY SEDIMENT CONTROL FACILITIES DURING CONSTRUCTION. DO NOT OPERATE HEAVY EQUIPMENT WITHIN THE PERIMETER OF A BIORETENTION FACILITY DURING EXCAVATION, UNDERDRAIN PLACEMENT, BACKFILLING, PLANTING, OR MULCHING OF THE FACILITY. USE ALL SUITABLE EXCAVATED MATERIAL IN THE WORK. ALTERNATIVELY, LEGALLY USE, RECYCLE, OR DISPOSE OF ALL EXCAVATED MATERIALS ACCORDING TO 105.16 AND 105.17. EXCAVATE THE BIORETENTION CELL(S) TO THE DIMENSIONS, SIDE SLOPES, AND ELEVATIONS SHOWN ON THE CONTRACT PLANS. MINIMIZE THE COMPACTION OF THE BOTTOM OF THE BIORETENTION FACILITY BY THE METHOD OF EXCAVATION. EMBANKMENT WILL BE MEASURED AND PAID AS ITEM 203, EMBANKMENT, USING NATURAL SOIL, 703.16.A. THE BIORETENTION SOIL SHALL BE A UNIFORM MIX THAT IS FREE OF STONES, STUMPS, ROOTS, OR ANY OTHER OBJECT THAT IS LARGER THAN TWO INCHES. THE SOIL MAY CONSIST OF EXISTING SOIL, FURNISHED SOIL, OR A COMBINATION OF BOTH PROVIDED THAT IT MEETS THE FOLLOWING REQUIREMENTS: THOROUGHLY MIX THE BIORETENTION SOIL PRIOR TO PLACEMENT. TEST AND ADJUST THE PH AS PER CMS 659.02.B. ALL SAND USED SHALL MEET CMS 203.02.H, NATURAL GRANULAR MATERIALS. PLACE THE SOIL IN 12 INCH LIFTS AND CONSOLIDATE BY WATERING UNTIL SATURATED. CONSTRUCT THE UNDERDRAIN SYSTEM AS PER CMS 605. PLACE THE GRANULAR BACKFILL MATERIAL TO THE INVERT OF THE BIORETENTION SOIL. ENSURE A MINIMUM OF 2 INCHES OF GRANULAR COVER OVER THE UNDERDRAIN PRIOR TO PLACEMENT OF THE BIORETENTION SOIL. PLACE OBSERVATION WELLS AND CLEANOUTS WHERE SHOWN IN THE PLANS. CONNECT THE WELLS/CLEANOUTS TO THE PERFORATED UNDERDRAIN WITH THE APPROPRIATE MANUFACTURED CONNECTIONS. THE WELLS/CLEANOUTS SHALL EXTEND 6 INCHES ABOVE THE TOP ELEVATION OF THE BIORETENTION FACILITY MULCH. CAP THE WELLS/CLEANOUTS

PH RANGE: 5.2-7.0

COMPOSITION BY VOLUME

4 PARTS SAND – CMS FINE AGGREGATE AS PER 703

2 PARTS COMPOST – CMS 659.06

2 PARTS TOPSOIL – CMS 659.05

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WITH A THREADED SCREW CAP. CAP THE ENDS OF UNDERDRAIN PIPES NOT TERMINATING IN AN OBSERVATION WELL/CLEANOUT OR CONNECTED TO OTHER CONDUITS. PLACE TREES, SHRUBS, AND OTHER PLANT MATERIALS SPECIFIED FOR BIORETENTION FACILITIES AS SPECIFIED IN THE PLANS. PLANT MATERIALS WILL BE MEASURED AND PAID FOR PER CMS ITEM 661. APPLY NO PESTICIDES, HERBICIDES, AND FERTILIZERS DURING PLANTING, ESTABLISHMENT, OR MAINTENANCE UNDER ANY CIRCUMSTANCES. BIORETENTION CELLS WILL BE PAID FOR AS ITEM SPECIAL, BIORETENTION CELL AT THE CONTRACT BID LUMP SUM PRICE. THE PAYMENT WILL BE FULL COMPENSATION FOR ALL APPLICABLE INCIDENTALS NECESSARY TO SATISFACTORILY COMPLETE THE WORK. Designer Note: This plan note shall be used on all projects that have bioretention cell(s) identified in the plan. Embankment work to create the impoundment will be constructed and paid for as Item 203 Embankment, using natural soils, 703.16.A.

W102 INFILTRATION TRENCH (OR BASIN)

THIS PLAN UTILIZES INFILTRATION FOR POST CONSTRUCTION STORM WATER TREATMENT. CONSTRUCT THE COMPLETED INFILTRATION TRENCH(ES) (AND OR BASIN(S)) AFTER ALL CONTRIBUTING DRAINAGE AREAS ARE STABILIZED AS SHOWN IN THE CONTRACT PLANS AND TO THE SATISFACTION OF THE ENGINEER. DO NOT USE INFILTRATION DEVICES AS TEMPORARY SEDIMENT CONTROL FACILITIES DURING CONSTRUCTION. DO NOT OPERATE HEAVY EQUIPMENT WITHIN THE PERIMETER OF AN INFILTRATION DEVICE DURING EXCAVATION OR BACKFILLING OF THE FACILITY. Designer Note: This plan note shall be used on all projects that have infiltration trenches and or basins identified in the plan. Embankment work to create the impoundment will be constructed and paid for as Item 203 Embankment, using natural soils, 703.16.A.

W103 MANUFACTURED WATER QUALITY STRUCTURE

THIS PLAN UTILIZES MANUFACTURED WATER QUALITY STRUCTURES FOR WATER QUALITY TREATMENT. AREAS HAVE BEEN SHOWN IN THE PLANS FOR PLACEMENT OF AN OFF-LINE SYSTEM. PAYMENT FOR THESE DEVICES SHALL BE MADE AT THE CONTRACT UNIT PRICE FOR ITEM 895, MANUFACTURED WATER QUALITY STRUCTURE, TYPE ____. Designer Note: This plan note shall be used on all projects that have manufactured water quality structures identified in the plan. If more than one manufactured water quality structure is provided in the plans, a table shall be provided to indicate the location and type of each structure used. Supplemental specification 895 outlines the different types of structures (1-4). Manufactured systems may not be used without approval of the Hydraulics Section through a feasibility study. Contact the Hydraulics Section for an area dimension that shall be shown in the plan.

January 2015