Prepared by Prepared for City of Palm Coast, Florida January 27, 2015 Drainage Study Sections 30 & 34 for Development of City Wide Stormwater

Prepared by

Prepared for City of Palm Coast,

Florida

January 27, 2015

Drainage Study Sections 30 & 34 for Development of City Wide

Stormwater Management Master Plan

Singhofen & Associates, Inc. January 27, 2015

Comprehensive Approach for Priority Criteria

Visual Inspections of Aging InfrastructurePipe Ratings

Historical Records from Rainfall EventsVisual Inspections of Stormwater SystemPublic Works High Water Signage Areas

Complaints (Service Orders) from CitizensCustomer Service Calls Combined With Follow Up Inspections

Other Special SituationsHigh Groundwater Areas

City of Palm Coast Modeling Priority


Section Numbers

Sections Already Modeled

Next Sections To Be Modeled

City of Palm Coast Modeling Status

1 2 3 4 5 6 7 8 9 10 11

12 13 14 15 16 17 18 19 20 21 22

23 24 25 26 27 28 29 30 31 32 33

34 35 37 39 57 58 59 60 63 64 65

81


City of Palm Coast Modeling Status


Historic stormsMay 2009 Storm Event

Rainfall totals range = 20 – 25 inchesRainfall ~ 300 Year – 5 Day storm

September 2014Rainfall total 17-19 inchesRainfall >200 Year – 2 Day storm

May 2009 Storm Event “R” Section (Section 30) :

High water reported at or near homes at 3 locationsRoadway overtopping reported at approximately 5 locationsModel confirms storm conditions

“E” Section (Section 34) :High water reported at or near homes at 4 locationsRoadway overtopping reported at approximately 10 locationsModel confirms storm conditions

Current Study Findings


System Performance Evaluation For Ditches & Canals:

Service Level A: Flow is contained within the system (i.e., no flooding of major roadways, minor roadways, yards or buildings occurs)

Service Level B: Flow is contained within the right of way (i.e., flooding is limited to the outer lane of major roadways and right-of-way area of yards)

Service Level C: Flooding of minor streets precludes travel and flooding of yards is at the buildings but no structure flooding occurs.

Service Level D: Extensive flooding of yards including buildings.

Note: Level of Service Objective = “B” Level “C” is considered deficient

Level “D” is considered unacceptable

Level of Service Evaluations


System Performance Evaluation For Homes:

Home flooding evaluated relative to base flood (i.e., 100-year storm)City has required 1 foot of freeboard above 100-year elevation

Level of Service Evaluations

Freeboard


Section 30 (“R” Section) – Level of Service


Section 30 (“R” Section) High water levels due to:

Constrictions between residential areas and primary canal system Low ground or road elevations relative to downstream road elevations or flood stages in Pine Grove Canal

2 homes predicted to flood in a 100-year event Number of homes below City requirement for 100-year event = 19 % 9 Locations with secondary drainage deficiencies for 10 year event Nuisance flooding (2-year event) at 8 road crossings

Modeling Results


Section 30 (“R” Section) – Level of Service

Deficient secondary roads = 9

Secondary drainage deficiencies


Section 34 (“E” Section) – Level of Service


Section 34 (“E” Section) High water levels due to:

Constrictions between residential areas and primary canal system Low ground or road elevations relative to downstream road elevations or flood stages in East Hampton Canal

No homes are predicted to flood in a 100-year event Number of homes below City requirement for 100-year event = 18 % 4 Locations (Nodes) with secondary drainage deficiencies for 10 year eventNuisance flooding (2-year event) at 25 road crossings

Modeling Results


Section 34 (“E” Section) – Level of Service

Deficient secondary roads = 4

Secondary drainage deficiencies


Recommended Improvement Plan

Section 30 Improvements:Ditch and Pipe Modifications along Seven Locations

Cost$370,600

Cost$240,800

$611,400

Section 30 Level of Service Improvements:Homes below 100-year City requirement reduced to 17 %Roadway Deficiencies Eliminated

Section 34 Improvements:Ditch and Pipe Modifications Along Two Locations

Section 34 Level of Service Improvements:Homes below 100-year City requirement reduced to 16 %Roadway deficiencies eliminated

Grand-Total


“R” Section (Section 31) Improvements - 2012Ditch and Pipe Modifications

(Richardson Drive to Richmond Drive)Construction Cost = $130,530Engineers Estimate = $215,000

2012-2013 Program Results


2013-2014 Program Results

“B” Section (Section 35) Improvements - 2014Ditch and Pipe Modifications

(Bunker Hill Drive to Burnaby Lane)Construction Cost = $145,000Engineers Estimate = $220,700


2014-2015 Program

“L” Section (Section 37) Improvements – 2014-2015Ditch and Pipe Modifications

(Lindsay Drive to Lansing Lane)Engineers Estimate = $220,000


Current & Future Work


Current Work in Design Based on ModelModeling Completed / Design Pending CostsSection 30 Est. Construction Costs $370,600Section 34 Est. Construction Costs $240,800Permitting Cost $25,338

Future Work in Design Based on ModelSection 31 “R” – Phase 2Section 31 Phase 2 Est. Construction Costs $733,800Permitting / Utility coordination Cost $30,000 Sections 35&37 Capital Improvement Est. Construction Costs $3,339,200Permitting Cost $50,000

Future Model DevelopmentSections 1 & 2“F” Model Cost $46,615Permitting Cost $25,000

Current & Future Work

Grand-Total $4,861,353


Sections 30 and 34 ExpectationsContinue Maintenance and Selective ImprovementsCity Swale and Ditch Maintenance Has Reduced Future Capital Cost

Lessons Learned?

Documents

Prepared by Prepared for City of Palm Coast, Florida January 27, 2015 Drainage Study Sections 30 & 34 for Development of City Wide Stormwater