#13 Massachusetts Stormwater Regulations - VHBprojects.vhb.com/stormwaterseminars/presentations/13... · · 2011-05-20Massachusetts DEP Stormwater Management Regulations Training

PREPARED UNDER

The 319 Nonpoint Source Pollution Grant Program

FUNDED BY

MA Department of Environmental ProtectionBoston, MA

PREPARED BY

Vanasse Hangen Brustlin, Inc.Watertown, MA

The Center for Watershed ProtectionEllicott City, MD

Stacey DePasquale Engineering, Inc.

Source of Slide Show data and photos:Massachusetts DEP Stormwater Management Regulations Training Slide Show 2008

Horsley Witten Group, Inc.Sandwich, MA

Stacey DePasquale Engineering, Inc.Lawrence, MA

May 19, 2011

Leominster, MA

Trustees of the Reservations Doyle Center


Massachusetts DEP Stormwater Regulations

Massachusetts Department of Environmental Protection - Bureau of Resource Protection


Implemented under the Wetlands Protection Act (WPA)


2008 Stormwater Standards Updates & Goals

1. Increase Recharge of Stormwater2. Promote Low Impact Development (LID)3 E B R d l Th Al I3. Ensure Better Redevelopment That Always Improves

Existing Conditions4. Provide Better Environmental Protection5. Update For Advances in Science/Engineering Relative

to Stormwater Management Since the 1990s


MA Stormwater Changes:What Is DEP Trying to Do?

1. Increase Recharge of Stormwater• Adds needed water to local underground water suppliesg pp• Adds base flow to local streams and rivers• Through requiring larger infiltration volume



2. Promote LID: Low Impact Development• What is LID?• What is LID?

Structures that Mimic Natural Systems Decentralized

Examples: Rain Gardens Examples: Rain Gardens Site Design that Minimizes Impervious Surface

• Through Credits & Requiring “Consideration” of LID



3. Ensure that redevelopments always improve existing conditions

• Need to improve recharge, treatment and/or flooding • Something can ALWAYS be done• Scale of improvements “should reflect” scale of proposed projectScale of improvements should reflect scale of proposed project• Through requirement and common guidance



4. Provide Better Environmental Protection• Treatment Before Infiltration Less Expensive Than Cleaning Up

Streams & AquifersStreams & Aquifers• Responsibility for Operation and Maintenance Made Clearer• Special Focus on Critical Areas, Illicit Discharges & Land Uses with

Higher Potential Pollution Loads (LUHPPLs)Higher Potential Pollution Loads (LUHPPLs) • Through Requiring More Pretreatment


MA Stormwater Changes:What Is DEP Trying to Do?5. Reflect Learning in Stormwater Science Since the 1990s

• Many Studies over Last Decade Performance of Traditional BMPsPerformance of Traditional BMPs Performance of LID

• Through Revisions to TSS Removal Charts & Inclusion of Specific Kinds of LID TechniquesKinds of LID Techniques



Today, we will present . . .• How changes affect Stormwater Jurisdiction• Changes to the MA Stormwater Standards• Changes to the MA Stormwater Standards• Technical Calculations and O&M• Pollution Prevention & Environmentally Sensitive Site Design & LID

C ditCredits • Case Studies Showing How LID Works• Overview of Stormwater BMPs


i di iJurisdiction


JurisdictionJurisdiction

Eliminate Confusion as to Whether New Stormwater BMPs Create NewBMPs Create New Wetlands Jurisdiction

P l D i d E LID & Ab d

Thomas Maguire, MassDEP

Proposal Designed to Encourage LID & Above‐ground BMPs, & Further O&M

Only for Stormwater Facilities Built from Effective DateOnly for Stormwater Facilities Built from Effective Date Forward

Looking Back: Current Rules Apply


Operation of a Stormwater Management System After the Effective Date of the Proposed Regulations Does Not by Itself Create Additional Wetlands Resource Areas or BufferItself Create Additional Wetlands Resource Areas or Buffer Zones


Review of Proposed Modifications to Stormwater Management System Constructed After the Effective Date of the Proposed Regulations is Limited to:Date of the Proposed Regulations is Limited to:

Maintenance of the System’s SW Functionsy

Compliance with the Stormwater Standards

Compliance with Only Those Standards that Would Apply in the Absence of the Stormwater System y





St t M tStormwater Management Standards & Applicability


New Revisions to the Stormwater Standards

MassDEP to Incorporate Stormwater Standards in Wetland & 401 Regulation

Advisory Committee Assisted MassDEP

4 Public hearings & over 200 comments

Regulations Effective January 2 2008 Regulations Effective January 2, 2008


Standards RevisedStandards RevisedApplicability Substantive ChangesStandard 1: No Untreated No Substantive ChangesDischarges/Erosion

Standard 2: Peak Rate Control No Substantive ChangesStandard 3: Recharge Substantive Changeg gStandard 4: Water Quality Substantive and Minor ChangesStandard 5: LUHPPLs Substantive ChangesStandard 6: Critical Areas Minor ChangesStandard 6: Critical Areas Minor ChangesStandard 7: Redevelopment Minor ChangesStandard 8: Construction Period Minor Changes

Standard 9: O&M Minor ChangesStandard 10: Illicit Discharges New StandardJurisdiction Minor Changes O/M jurisdiction


Jurisdiction Minor Changes O/M jurisdictionMajor change BMP jurisdiction

ApplicabilityApplicability

Stormwater Standards Apply when a Wetlands or 401 Permit R i dRequired:

Industrial Uses,, Commercial Uses, Institutional Uses,

Offi U Office Uses, Residential Uses, and Transportation Projects.Transportation Projects.

Includes Site Preparation, New Construction & Redevelopment, & Stormwater Discharges


Stormwater Discharges

How Do Stormwater Management Standards Apply to:

1. Small Residential Projects a. Detached Single‐family Dwellings on Four or Fewer Lotsb. With Stormwater Discharge that May Potentially Affect

Critical Area;

2 S ll M lti f il H i2. Small Multi‐family Housing a. Four or Fewer Units, includes Condominiums,

Cooperatives, Apartment Buildings, & Townhousesb. With Stormwater Discharge that May Potentially Affect

Critical Area;


How Do Stormwater Management Standards Apply to:

3. Housing Development & Redevelopment Projects

a Detached Single family Dwellings on Five to Nine Lotsa. Detached Single‐family Dwellings on Five to Nine Lotsb. No Stormwater Discharge May Affect Critical Area;

4. Multi‐family Housing Projects

a. Five to Nine Units, e.g. Condominiums, Cooperatives, Apartment Buildings, & Townhousesb. No Stormwater Discharge May Affect Critical Area;


How Do Stormwater Management Standards Apply to: 5. Marinas & Boat Yards

Hull Maintenance, Painting & Service Areas are Protected from Exposure to Rain, Snow, Snow Melt, & Stormwater Runoff to the p , , ,Maximum Extent Practicable. Good pollution prevention.


How Do Stormwater Management Standards Apply to: 6. Footpaths, Bike Paths & Other Paths

Encourage Paths for Pedestrian &/or Non‐motorized Vehicle Access to Maximum Extent PracticableAccess to Maximum Extent Practicable.


S

Land Use

Summary

Industrial Uses Apply Fully

Commercial Commercial Uses Apply FullyUsesInstitutional UsesInstitutional UsesInstitutional UsesInstitutional Uses

Offi UOffi UOffice UsesOffice Uses Apply Fully

Apply Fully

Office UsesOffice UsesOffice Uses Apply Fully

Residential UsesResidential UsesResidential Uses See Residential Table and

ExemptionsTransportation

Land Uses Not Specifically

See Exemptions, Otherwise SubjectApply Fully

Transportation

Land Uses Not Specifically


ExemptedExempted

General Rule >4 lots/units with discharge to critical area OR≥10 lots or units

≤ 4 lots/units with discharge to critical areaOR5 to 9 lots/units with no≥10 lots or units 5 to 9 lots/units with no discharge to critical area

Single Family Apply Fully Apply Max. Extent

PracticableFamily Detached Dwellings

Practicable

Multi-Family Dwellings Apply Fully Apply Max. Extent

PracticableMarinas and Boat Yards

Apply Max. Extent Practicable

Footpaths, bike paths and other “paths”

Apply Max. Extent Practicable


p

Exemptions ‐ Stormwater Standards Don’t Apply To: A Single‐family house project Residences of Four or Fewer Units

• E.g. Condominiums, Cooperatives, Apartment Buildings & TownhousesTownhouses

• No Stormwater Discharges that May Affect Critical area; and Emergency Repairs to Roads or their Drainage Systems Projects that Don’t Require Wetlands & 401 Permits


St d d 3Standard 3:Recharge




Goals

1 By Increasing Recharge of Stormwater1. By Increasing Recharge of Stormwater• Adds Needed Water to Local Underground & Surface Water

Supplies• Adds Base Flo to Local Streams & Ri ers• Adds Base Flow to Local Streams & Rivers

Through Requiring Larger Infiltration Volume• Reduce Impervious Surface• Support & Improve Wildlife Habitat, Fisheries Functions &

Recreational Uses


i h h lHigher Recharge Volumes

Hydrologic New Old RechargeHydrologic Group

New Recharge Depth x Total I i

Old Recharge Depth x Total Impervious AImpervious

AreaArea

A 0.60 inches 0.40 inches

B 0.35 inches 0.25 inches

C 0 25 inches 0 10 inchesC 0.25 inches 0.10 inches

D 0.10 inches waived


Example (Assume Using Static Method)

Office Building with Parking Lot on “A” Soil (Sandy Soil) g g ( y )with 2 Acres of Impervious Surfaces Old Recharge Volume: 2,615 CF N R h V l 4 356 CF New Recharge Volume: 4,356 CF

What Could this Mean for Infiltration Basin Size? Old Recharge Volume: 35 ft. x 25 ft. (3 ft. deep) New Recharge Volume: 58 ft. x 25 ft. (3 ft. deep) New “Dynamic” Rules May Reduce Size New Dynamic Rules May Reduce Size


Rules for Groundwater Recharge

At least 44% of the TSS Must be Removed Prior to Discharge to Infiltration Structure if:

h llh d Within a Zone II or Interim Wellhead Protection Area; Near Outstanding Resource Water; Near Special Resource Water; Near Shellfish Growing Area; Near Cold‐water Fishery; Near Bathing Beach; Near Bathing Beach; From Land Uses with Higher Potential Pollutant Loads; or In Area with Rapid Infiltration Rate (> 2.4 inches/hour).


Rules for Groundwater Recharge (continued)

Discharges of Runoff from Non‐Metal Roof to Dry Well May Be Discharged to the Ground without Pretreatment.

Discharges of Runoff from Metal Roof (galvanized steel or ) i i hcopper) Requires Pre‐Treatment using BMP that Removes

Metals if Discharge is in Zone II , Interim Wellhead Protection Area &/or at Industrial Site.

Depth to Ground Water: Two Feet or More Vertical


Separation

All infiltration str ct res m st be able to drain f ll ithin 72 ho rs

Rules for Groundwater Recharge (continued)

All infiltration structures must be able to drain fully within 72 hours. General Setbacks Requirements (see Volume 2 for other BMP‐

Specific Setbacks)p ) Soil Absorption Systems: 50 feet Public Wells: Outside Zone I Public Reservoir, Surface Water Sources & their Tributaries:

Outside Zone A Other Surface Waters: 50 feet Other Surface Waters: 50 feet Property Line: 10 feet Specific BMPs have Additional Setback Requirements (See Vol 2)


Specific BMPs have Additional Setback Requirements (See Vol. 2)

Low Impact Development Site Design Credits Low Impact Development = LID Credits to meet all or part of

Standard 3 (Recharge) and Standard 4 (Water Quality)Standard 4 (Water Quality)

Theory Behind Credits Less impervious area = less

impact on wetlandsimpact on wetlands Goal of Credit: Reduce

Impervious Area

Center for Watershed Protection


Center for Watershed Protection

3 LID Site Design CreditsLID Site Design Credit 1 Environmentally Sensitive Development

LID Site Design Credit 2 Disconnected Rooftop Runoff

LID Site Design Credit 3 Disconnected Non‐Rooftop RunoffDisconnected Non Rooftop Runoff


Credit 1: Environmentally Sensitive Development

Credit Based on EOEA Smart Growth Tool Kit Total Impervious Area Must be <15% of Site Area A Mi i 25% f Sit M t b P t t d N t l A Minimum 25% of Site Must be Protected as Natural

Conservation Area LUHPPL Not Eligible for this Creditg A Conservation Restriction Must be

Placed on the Protected Area


Credit 2: Disconnect Rooftop Runoff

Based on EOEA Smart Growth Tool Kit Runoff cannot be from “LUHPPLs” Every 1000 sq ft of Impervious Area Must have at Least 75 ft

Pervious Sheet Flow


Pervious Sheet Flow Path Must• Be Vegetated• Be At Least 10 ft from any Pervious AreaBe At Least 10 ft from any Pervious Area• Have Slope of < 5%• Not Go Over Septic or Subsurface SW Recharge Systems

LUHPPL G R f M l R f N Eli ibl f C di


LUHPPL, Green Roof, or Metal Roof Not Eligible for Credit

Credit 3: Disconnect Non‐Rooftop Runoff

Based on EOEA Smart Growth Tool Kit Roadways, Driveways, Parking Lots Every 1000 sq ft of Impervious Area Must have at Least 75 feet

Pervious Sheet Flow P i Sh t Fl P th M t Pervious Sheet Flow Path Must

• Be Vegetated• At Least 10 ft from any Pervious Area• Have Slope of < 5%• Not Go Over Septic or Subsurface SW Recharge Systems

LUHPPL eligible for this Credit except High Intensity Parking Lots


LUHPPL eligible for this Credit except High Intensity Parking Lots

DON’T

Standard 4: Water QualityDON T FORGET TO ADSORB YOUR SUSPENDED SEDIMENT

Greater Emphasis on Source Controls Long‐term Pollution Prevention Plan g

Required New BMPs added to MassDEP TSS

Removal TableRemoval Table Update TSS Removal Numbers to

Reflect Latest Science


New BMP TablesTSS Removal Efficiencies for Best Management Practices

Best Management Practice (BMP) TSS Removal Efficiency

New BMP Tables

Street Sweeping 0‐10%, See Volume 2, Chapter 1.

Non‐Structural Pretreatment BMPs

Structural Pretreatment BMPs

Deep Sump Catch Basins 25% only if used for pretreatment and l if ff lionly if off‐line

Oil Grit Separator 25% only if used for pretreatment and only if off‐line

Proprietary Separators Varies – see Volume 2p y p

Sediment Forebays 25% if used for pretreatment

Vegetated filter strips 10% if at least 25 feet wide, 45% if at


least 50 feet wide

TSS Removal Efficiencies for Best Management Practices

Best Management P ti (BMP)

TSS Removal Efficiency

Treatment BMPs

Bioretention Areas 90% provided it’s combined with a vegetated filter

Practice (BMP)

including Rain Gardensp g

strip or equivalent pretreatment BMP

Constructed Stormwater 80% provided it’s combined with sedimentConstructed Stormwater Wetlands

80% provided it s combined with sediment forebay or equivalent pretreatment BMP

Extended Dry Detention 50% provided it’s combined with sediment yBasins

pforebay or equivalent pretreatment BMP

Gravel Wetlands 80% provided it’s combined with sediment f b l


forebay or equivalent pretreatment BMP


Best Management Practice (BMP)


Proprietary Media Filters

Varies – see Volume 2

ac ce ( )Treatment BMPs

Filters

Sand/Organic Filters 80% provided it’s combined with one or more pretreatment BMPs1

Treebox Filter 80% provided it’s combined with sediment forebay or equivalent pretreatment BMP

Wet Basins 80% provided it’s combined with sediment forebay or equivalent pretreatment BMP


q p


Best Management Practice TSS Removal Efficiency

Conveyance

(BMP)

50% if combined with sediment forebay or

Drainage Channels For conveyance only. No TSS Removal credit.

Grass Channels (formerly 50% if combined with sediment forebay or equivalent pretreatment BMP

Grass Channels (formerly biofilter swales)

Water Quality Swale wet & dry

70% provided it’s combined with sediment forebay or equivalent1 pretreatment BMP



Best Management Practice (BMP)


Infiltration BMPs

Dry Wells 80% for runoff from non‐metal roofs, may also be used for runoff from metal roofs only if metal roof is notfor runoff from metal roofs only if metal roof is not located within a Zone II, or IWPA or at an industrial site

Infiltration Basins & 80% provided it’s combined with one or moreInfiltration Basins & Infiltration Trenches

80% provided it s combined with one or more pretreatment BMPs1 prior to infiltration

Leaching Catch Basins 80% provided a deep sump catch basin is used for pretreatment

Subsurface Structure 80% for non proprietary structures provided they are combined with one or more pretreatment BMPs1 prior


to infiltration; proprietary see Volume 2

N BMP T blNew BMP TablesTSS Removal Efficiencies for Best Management Practices

Best Management TSS Removal Efficiency

Other BMPs

i i

gPractice (BMP)


Dry Detention Basins For peak rate attenuation only. No TSS Removal credit.

Green Roofs Green Roof See Volume 2. May reduce required water quality volume No TSS Removal Creditwater quality volume. No TSS Removal Credit.

Porous Pavement 80% if designed to prevent run‐on and with adequate storage capacity. Limited to uses identified in Vol. 2.

Rain Barrels and Cisterns

May reduce required water quality volume. No TSS Removal Credit.

Note: 1. If pretreatment is required, removal efficiency includes the terminal treatment BMP and the pretreatment BMP. For example, Leaching catch basin‐ 80% is the total removal efficiency for both the leaching catch basin and the deep sump catch basin No additional TSS credit is given for deep sump catch basin


deep sump catch basin. No additional TSS credit is given for deep sump catch basin.

Total Maximum Daily LoadTotal Maximum Daily Load (TMDLs)

185 Approved TMDLs More TMDLs Under Development BMPs Must Meet TSS

Requirements & be Consistent with TMDLs Thomas Maguire, MassDEP


Proprietary BMPs Examples:

• Proprietary Separators, Media Filters Some States: Must be Approved by State Before Used

M h tt M B U d If Massachusetts: May Be Used If ‐• Verified by Conservation Commission as Part of Order of Conditions• STEP Evaluation (Legacy Only – To Be Phased Out)( g y y )• Completed TARP Review


P i t BMPProprietary BMPs(continued)

Old Verification Process: Less Guidance New Verification Process: More Guidance & Explicit

R li G d St diReliance on Good Studies• UMass Stormwater Database

http://www.mastep.net/

• Evaluation Guidance in Handbook• Explicit Language: “Strongly Recommend”


Standard 5:Land Use with Higher Potential Pollutant Load (LUHPPL)

Recharge from LUHPPL Required in Zone II Drinking Water Areas

Specific Pretreatment for LUHPPL Required (44% TSS Removal) Specific Pretreatment for LUHPPL Required (44% TSS Removal) More Treatment Required: 1‐inch rule Specific Source Controls & Structural BMPs will be Described

that Each Different Type of LUHPPL Must Provide Update List of BMPs that are Appropriate for LUHPPL Based on

Latest ScienceLatest Science


Example: Pollution Prevention

Thomas Maguire MassDEP




Discharges from Certain LUHPPLs May be Subject to

Best Management Practices for LUHPPLs (Standard 5)

Discharges from Certain LUHPPLs May be Subject to Additional Requirements (Including Obtaining Individual or General Discharge Permit).

Must Implement Source Control & Pollution Prevention.

All BMPs Designed in Accordance with Specifications in the Massachusetts StormwaterHandbook Volume 2.Handbook Volume 2.

Required Water Quality Volume Equals 1‐inch X Total Impervious Area of Project


Impervious Area of Project.

Many Land Uses Have the Potential to Generate


Many Land Uses Have the Potential to Generate Higher Potential Pollutant Loads of Oil & Grease.

Examples Include: Examples Include:• Industrial Machinery & Equipment• Fueling Stations, Vehicle Maintenance & Repair• Construction Businesses• Paving, Heavy Equipment Storage, Maintenance• High Intensity Parking Lots & Fleet Storage Areas etc• High Intensity Parking Lots & Fleet Storage Areas, etc.


The Following BMPs must Pre‐treat the Runoff Prior to


The Following BMPs must Pre treat the Runoff Prior to Discharge to an Infiltration Structure: • Oil Grit Separator• Sand Filter• Filtering Bioretention Area

44% TSS Removal Required Prior to Discharge to an Infiltration Device.


LUHPPL TSS PretreatmentNew Tables

PretreatmentDeep Sump Catch Basin

Oil Grit Separator

Proprietary Separators See Volume II.

Sediment ForebaysSediment Forebays

Vegetated Filter Strip (must be lined)


LUHPPL TSS TTreatmentS d filt O i filt P i t Filt i Bi t ti A

LUHPPL TSS Treatment

Sand filters, Organic filters, Proprietary Media Filters, Wet Basins, Filtering Bioretention Areas, and Extended Dry Detention Basins must be lined and

Filtering Bioretention Areas including rain gardensConstructed Stormwater Wetlands

sealed unless at least 44% of TSS has been removed prior to discharge to the BMP

Dry Water Quality Swales

Extended Dry Detention Basins

Gravel Wetlands

Proprietary Media Filter

Sand / Organic Filters

Bioretention Areas including rain


Bioretention Areas including rain gardens with under drain

LUHPPL:Stormwater Infiltration

I filt tiInfiltrationExfiltrating Bioretention Areas including rain gardens no under draindrain

Infiltration Basins

Infiltration Trenches

Leaching Catch Basins

Subsurface StructuresSubsurface Structures


Standard 6:Critical AreasCritical Areas

44% TSS Removal Required44% TSS Removal Required for Pretreatment Prior to Infiltration

Discretion May Be Exercised to Require Removal of Other Constituents to Prevent Pollution to Wetlands


• Especially Critical if TMDL Established or Redevelopment Site• Updated Latest BMP Based on Current Science


New Tables for Critical AreasNew Tables for Critical AreasStormwater BMPs for Shellfish Growing Areas and Bathing BeachesIf applicable, proponent must comply with Coastal Wetlands Regulations[1].All BMPs must be designed in accordance with specifications in Volume 2 of the

Pretreatment: Oil Grit Separators

All BMPs must be designed in accordance with specifications in Volume 2 of the Massachusetts Stormwater Handbook.

Proprietary Separator See Volume II

Deep Sump Catch Basin

Sediment ForebaySediment Forebay

Vegetated Filter Strip


[1] Coastal Wetlands Regulations – http:///www.mass.gov/dep/service/regulations/310cmr10a.pdf#41

Stormwater BMPs for Shellfish Growing Areas and Bathing BeachesIf applicable, proponent must comply with Coastal Wetlands Regulations[1].All BMPs must be designed in accordance with specifications in Volume 2 of the Massachusetts Stormwater Handbook

Constructed Stormwater Wetland(highly recommended)

Massachusetts Stormwater Handbook.

Treatment:

Sand filters, Organic Filters, Proprietary Media Filters, Filtering Bioretention Areas

Gravel Wetland

Sand / Organic FiltersFiltering Bioretention Areas and Wet Basins must be lined and sealed if at least 44% TSS has not been removed prior to di h t th BMP

Proprietary Filter Media See Volume II.

Filt i Bi t ti A i l didischarge to the BMP Filtering Bioretention Areas including rain gardens

Wet Basin


Stormwater BMPs for Shellfish Growing Areas and Bathing BeachesIf applicable, proponent must comply with Coastal Wetlands Regulations[1].All BMPs must be designed in accordance with specifications in Volume 2 of the Massachusetts Stormwater Handbook

Infiltration: Infiltration Trenches (highly recommended)

Infiltration Basins (highly recommended)

Massachusetts Stormwater Handbook.

Infiltration Basins (highly recommended)

Dry Wells

Exfiltrating Bioretention Areas including rain gardens

Subsurface Structures


ORWs

Stormwater Discharges that may impact Outstanding Resource Waters including Vernal Pools & Surface Water Sources for Public Water Systems

1. Construction Sites of 1 Acre or More Must File a Notice of Intent (WM 08B) with MassDEP if They Discharge to an ORW.

2. Stormwater Discharges to ORWs• Must be Set Back from Receiving Water or Wetland• Highest & Best Practical Method of Treatment. • If Discharge is from LUHPPL or Significant Source of Pollutants

Additional Requirements May Apply


Stormwater Discharges that May Impact Outstanding Resource Waters including Vernal Pools & Surface Water Sources for Public Water Systems

3. Stormwater Management to a Certified Vernal Pool• Stormwater Mgmt Systems Should Avoid Impacts to Vernal Pool.• Must be Set Back 100 Ft & Comply with 310 CMR 10 60• Must be Set Back 100 Ft & Comply with 310 CMR 10.60.• Habitat Evaluation Required • Must Demonstrate Will Meet Performance Standard of No Adverse

Impact on Habitat Functions of a certified vernal pool.

4. Unless Essential to Operate Public Water System, Stormwater BMPs Prohibited within Zone A.

5. Assumes BMPs have been Designed to the Specifications in Volume 2 of the Massachusetts Stormwater Handbook.


Stormwater Discharges may impact Outstanding Resource Waters including vernal pools and Surface Water Sources for Public Water Systems

• Unless necessary to manage stormwater from essential drinking water• Unless necessary to manage stormwater from essential drinking water facilities, no stormwater BMPs should be located within the Zone I

• Proponents must comply with local source water protection ordinances, bylaws, and regulations., y , g

• The Drinking Water Regulations, 310 CMR 22.21(2)(b)(7), require the development of land use controls in the Zone II that prohibit land uses that result in rendering 15% or 2500 square feet of a lot impervious,

hi h i l l t f tifi i l h th t d twhichever is larger, unless a system of artificial recharge that does not degrade groundwater quality is provided. Developers can comply with these land use controls by designing, constructing, operating and maintaining a stormwater management system in compliance with the g g y pStormwater Management Standards.

• BMPs must be designed according to the specifications in Volume 2 of the Massachusetts Stormwater Handbook.


Stormwater Discharges within Zone Is, IIs & Interim Wellhead Protection areas

Pretreatment BMPSOil Grit SeparatorDeep Sump Catch Basin Sediment ForebayVegetated Filter StripP i t S t S V l IIProprietary Separators See Volume II.

Treatment BMPsSand Filters, Organic Filters, Proprietary Media Filters, Filtering Bioretention areas, and Wet Basins must be lined and sealed unless 44% of TSS has been removed

Constructed Stormwater Wetlands Filtering Bioretention Area including rain gardensSand / Organic FiltersProprietary Filter Media See Volume IIlined and sealed unless 44% of TSS has been removed

prior to discharge to the BMP.Proprietary Filter Media See Volume II.Wet Basin Gravel Wetlands

Infiltration BMPsInfiltration Trenches (highly recommended)Infiltration Basins (highly recommended)Infiltration Basins (highly recommended)Subsurface Structures (See Volume II)Dry wells (uncontaminated runoff from non-metal roofs only)Exfiltrating Bioretention areas including rain gardens


Best Management Practices for Cold Water FisheriesPretreatment Oil Grit Separator

Sediment Forebays

Deep Sump Catch Basins

Vegetated Filter Strips

Proprietary Separators (see volume 2)

Best Management Practices for Cold Water Fisheries

TreatmentSand Filters Organic filters

Dry Water Quality Swales

Wet Water Quality SwalesSand Filters, Organic filters, Proprietary Media Filters, Water Quality Swales, Grass Channels, and Filtering Bioretention Areas must be lined and sealed unless at least

Q y

Grass Channels

Sand / Organic Filters

Proprietary Filter Media (see volume 2)44% TSS has been removed prior to discharge to the BMP.

p y ( )

Filtering Bioretention Areas including Rain gardens with linings

Leaching Catch Basins

P P t


Porous Pavement

Best Management Practices for Cold Water Fisheries

Infiltration Infiltration TrenchesInfiltration Infiltration Trenches

Infiltration Basins

S b f St t (SSubsurface Structures (See Vol 2)

Exfiltrating Bioretention Areas gincluding rain gardens

Dry WellsDry Wells


Standard 7: Redevelopment

No New Untreated Stormwater Discharges Construction Period Controls RequiredConstruction Period Controls Required Long term Pollution Prevention & O/M Plans Required Other Stormwater Standards Must be Met to Maximum Extent Ot e Sto ate Sta da ds ust be et to a u te t

Practicable Redevelopment Checklist Must be Completed Redevelopment Should Improve Existing Conditions


Written Erosion & Sediment Control &Standard 8: Construction Controls

Written Erosion & Sediment Control & Pollution Prevention Plan

Minimum Plan Standards Minimum Plan Standards

Standards for Plan Implementation p(e.g. Inspections, Adjusting Erosion Controls if Failing)


NPDES SWPPP Can Serve as Required Plan


Standard 9: Post Construction OperationStandard 9: Post Construction Operation & Maintenance (O/M)

Stormwater BMPs Must be Operated & Maintained Properlyp y




O/M Plan Required

Operation & Maintenance Plan

Responsible Party Must Be Designated in PlanDesignated in Plan

Plan Must Be ImplementedPlan Must Be Implemented

Maintenance Log Must Be Thomas Maguire, MassDEP

Kept


Typical Maintenance FrequenciesMinimum Frequencies Specified in MassDEP Stormwater Handbook V l 2Volume 2

Parking Lot Sweeping• Sweep at Frequency Specified in O/M Plan• Sweep at Frequency Specified in O/M Plan

Deep Sump Catch Basins• Inspect Quarterly

Sediment Forebayy• Inspect Quarterly• Clean Twice a Year or When

Sediment Depth is 3‐6 ft Extended Dry Detention Basins Extended Dry Detention Basins

• Inspect at Least Twice a Year & During & After Major Storms


O/M Permitting Guidance

MassDEP will Supply Suggested “Continuing Conditions” for Certificate of Compliance

• Operator Must Maintain BMPOperator Must Maintain BMP

• Operator Can’t Alter or Replace BMP w/o Con Com Review– Limited Only to Ensure Stormwater Standards Met

• Municipal Agency has to “Sign‐off” on O/M Plan if Municipality Takes Over Maintenance


Standard 10: Illicit Discharges

New Standard No Illicit Discharges to Wetlands or Storm Drain

Systems


Provides Consistency with MS4 NPDES Permit Only Have to Remove or Stop Illicit Discharges in

C t l f A li t N t Th Off itControl of Applicant – Not Those Off‐site Pollution Prevention Plan Should Include Measures to

Prevent Illicit Discharges


Prevent Illicit Discharges

What are Illicit Discharges?What are Illicit Discharges? Any Non-Stormwater Discharge, Except . . .

Water Line Flushing Water from Crawl Space Pumps

Landscape Irrigation Footing DrainsLandscape Irrigation Footing Drains

Diverted Stream Flows Lawn Watering

Rising Ground Waters Individual Resident Car Washing

Uncontaminated Ground Water Infiltration Flows from Riparian Habitats and WetlandsUncontaminated Ground Water Infiltration Flows from Riparian Habitats and Wetlands

Uncontaminated Pumped Ground Water Dechlorinated Swimming Pool Discharges

Discharge from Potable Water Sources Street W\ash Water, and

Foundation Drains Residential Building Wash Waters, without Detergentsg

Air Conditioning Condensation Fire fighting activities during emergency situations*

Irrigation Water, Springs


Same as EPA’s list in NPDES MS4 permit

Maintenance of a Stormwater Management System Constructed in Accordance with the SW Standards Does Not by Itself Trigger Filing of a Notice of IntentNot by Itself Trigger Filing of a Notice of Intent


Technical Calculations


The Three Components of Stormwater Management

1. Site Planning2. Source Controls 3. Structural BMPs



1. Site Planning• Design the Development to . . .

Retain Natural VegetationRetain Natural Vegetation Minimize Impervious Surface Slow Down Time of Concentration Reduce RunoffReduce Runoff

• Using Environmentally Sensitive Site Design & LID Techniques



2. Source Controls• Nonstructural Measures to Prevent Pollution or Control It at Its

Source• Includes:

Source Control Pollution PreventionPollution Prevention Construction Period Erosion & Sediment Controls



3. Structural BMPs• Purposes:

Attenuate Peak FlowsAttenuate Peak Flows Capture & Treat Runoff Provide Recharge

• Must Design Construct AND MaintainMust Design, Construct AND Maintain


Best Management Practices (BMPs)


Stormwater BMPs

Structural Pretreatment BMPs Treatment BMPsTreatment BMPs Conveyance Infiltration BMPs Other BMPs


Stormwater BMPs:Structural Pretreatment BMPs

Deep Sump Catch Basins Oil/Grit Separator/ p Proprietary Separators Sediment Forebays Vegetated Filter Strips






Oil/Grit Separator


Oil/Grit Separator


Proprietary SeparatorsProprietary Separators


Sediment Forebays


Vegetated Filter Strips


Stormwater BMPs:Treatment BMPs

Bioretention Areas including Rain Gardens Constructed Stormwater Wetlands Extended Dry Detention Basins Proprietary Media Filters

S d & O i Filt Sand & Organic Filters Wet Basins


Bioretention AreasBioretention Areas Including Rain Gardens


d l dConstructed Stormwater Wetlands


Extended Dry Detention Basins


Proprietary Media FiltersProprietary Media Filters


Sand Filter


Organic Filter (Treebox)Organic Filter (Treebox)


Wet BasinsWet Basins


Stormwater BMPs:Conveyance

Drainage Channels Grass Channels (Formerly Biofilter Swales) Grass Channels (Formerly Biofilter Swales) Water Quality Swale – Wet & Dry


D i Ch lDrainage Channels


Grass ChannelsGrass Channels(Formerly Biofilter Swales)


Water Quality Swale – Wet & DryWater Quality Swale – Wet & Dry


Stormwater BMPs:Infiltration BMPs

Dry Wells Infiltration Basins & Infiltration TrenchesInfiltration Basins & Infiltration Trenches Leaching Catch Basins Subsurface Structure


Stormwater BMPs:Infiltration BMPs

C iti l I S tb k Critical Issue: Setbacks General Setback Requirements:

• Soil Absorption Systems for Title 5 System: 50 feetSoil Absorption Systems for Title 5 System: 50 feet• Private wells: 100 feet• Public wells: Outside Zone I• Public reservoir, surface water sources for public water systems

and their tributaries: Outside Zone A• Other surface waters: 50 feetOther surface waters: 50 feet• Property Line: 10 feet


Dry WellsDry Wells


Infiltration BasinsInfiltration Basins


Infiltration TrenchesInfiltration Trenches


Leaching Catch BasinsLeaching Catch Basins


Subsurface StructureSubsurface Structure


Stormwater BMPs: Other BMPs

Dry Detention Basinsy Green Roofs Porous Pavement Rain Barrels & Cisterns


Dry Detention BasinDry Detention Basin


Green RoofsGreen Roofs


fGreen Roof

Green Roof Sized to Hold Water QualityGreen Roof Sized to Hold Water Quality Volume

Eligible for Water Quality Volume Credit, but not Recharge Credit Since Green Roof Intercepts Approximately 90% of StormsIntercepts Approximately 90% of Storms

Green Roof atop a LUHPPL is Eligiblep g


Porous PavementPorous Pavement


Rain Barrels & CisternsRain Barrels & Cisterns


A Final Word on BMPs

Above Ground or Below Ground? Natural Look or Industrial Look? Multiple BMPs Increase Reliability Multiple BMPs Increase Reliability MassDEP Encouraging LID


Closing Comments


Summary

1. Increase Recharge of Stormwater2. Promote LID: Low Impact Developmentp p3. Ensure that redevelopments always improve existing

conditions4 P id b tt i t l t ti4. Provide better environmental protection5. Reflect learning in stormwater science since the 1990s


Key Stormwater Rules ‐ Local

Conservation Commissions Apply State Wetlands Act Locally• Wetlands Regulations include Stormwater Standards

MS4 Permit Requires “Locally Enforceable Mechanisms”MS4 Permit Requires Locally Enforceable Mechanisms• For Construction, “Post‐construction” and Illicit Discharge

Related Local Initiatives – e.g., Subdivision Rules, Well P t ti Z S t G th R l C h iProtection Zones, Smart Growth Rules, Comprehensive Stormwater Bylaws, LID Bylaws


Key MassDEP Stormwater Sources of Information

/• www.mass.gov/dep Select and click Stormwater in “Quick Links” Scroll down for Stormwater Handbook Information

l• [email protected] To send comments to MassDEP about interim guidance

• MassDEP Wetlands Circuit Rider Program www.mass.gov/dep/water/resources/cridr.htm

• Key Staff Members [email protected] [email protected] s [email protected] [email protected]


CONTACT INFORMATION

Bethany E. EisenbergDirector of Stormwater Services

| li

Deb CaracoCenter for Watershed Protectioni ld ffi hVHB | Vanasse Hangen Brustlin, Inc.

101 Walnut StreetWatertown, MA 02472Phone: 617.924.1770 x1229 | Fax: 617.924.2286 Direct: 617.607.1852 beisenberg@vhb com

Field Office: 606 N. Aurora St., Ithaca, NY 14850Main Office: 8390 Main Street, 2nd Floor, Ellicott City, MD 21043 [email protected] cwp [email protected]

www.vhb.com

Richard A. Claytor, Jr., P.E.Principal EngineerHorsley Witten Group

www.cwp.org

Stacey A. DePasquale, P.E.PresidentSDE354 M i k S S i 20090 Route 6A, Sandwich, MA 02563

508‐833‐[email protected]

354 Merrimack Street, Suite 200Lawrence, MA 01843‐1755978‐975‐0500sdepasquale@sde‐inccomhttp://www.sde‐inc.com/


www.vhb.com/stormwaterseminars

Documents

#13 Massachusetts Stormwater Regulations - VHBprojects.vhb.com/stormwaterseminars/presentations/13... · · 2011-05-20Massachusetts DEP Stormwater Management Regulations Training