Fort Walton Beach Council agenda — 05-25-2010 Regular — reading text

Provide stormwater treatment for 8 medium density residential acres of drainage area within the Gap Creek Basin that directly impacts the water quality of Cinco Bayou and Choctawhatchee Bay. 2. Reduce the nonpoint source pollutant loading of nutrients, suspended solids, heavy metals, and other urban non -point source pollutants into the Choctawhatchee Bay system. Restore and protect the natural biological communities, recreational and aesthetic qualities of this diverse resource for future generations. 3. Provide additional storage and attenuation of stormwater to help reduce non -point source pollution in an industrial area that has a potential for significant pollutant loading related this type of land use activities in the watershed. Attenuation of flow will also provide flood relief for downstream areas near Gap Creek. 4. Increase public awareness of the value of area water resources, the importance of preventing non -point source pollution, and best management practices for pollution prevention. PROJECT DESCRIPTION: The proposed stormwater retrofit pollution reduction project will consist of a drilled down residential community pollution education outreach program and a treatment retrofit including the following components: Bay Street Bioretention The existing . 1 acre retention area designed as a dry pond does not perform as designed and holds water for prolonged periods of time. Proposed improvements include bottom filtration for solids removal with lateral conveyance to Gap creek, bio retention construction, and plant selection that will optimize nutrient uptake, and increase evapotranspiration. Proper plant selection will assure that the project is aesthetically pleasing and will garner public support and protection. 2. Burnette Avenue Bioretention Proposed improvements The existing depressed gravel area provides negligible treatment. include removing the gravel, increasing the depression and providing bottom filtration for solids removal with lateral conveyance to Gap Creek. Similar to Bay Street, Bio retention construction, and plant selection will optimize nutrient uptake and increase evapotranspiration. Proper plant selection will assure that the project is aesthetically pleasing and will garner public support and protection. 29_ 3. Public Outreach and Education CBA is a local community based organization dedicated to protecting the Choctawhatchee Bay system. They provide public education about environmental stewardship and organize public involvement related to trash clean up events and restoration projects on and around the bay. CBA often partners with the City to help publicize the City' s projects and other programs directed at reducing nonpoint source pollution to the bay and other conservation measures to reduce pollution and protect natural resources. CBA will be a partner on this project to increase public awareness of the value of area water resources, the importance of preventing non -point source pollution, and best management practices for pollution prevention.They will provide public outreach specific to the immediate residential community and educational press releases about the project. A "volunteer event( s)" will be coordinated by CBA during the project for volunteers to participate with helping plant native vegetation in the littoral zones of the facilty and /or provide trash cleanup around the project site and in the watershed. As the construction of the facility nears completion, the City and CBA will partner to provide an on site program for the residents. This program will be developed to inform attendees of the purpose for the construction project, provide information about the Gap Creek Watershed and the path that contributing runoff takes once it leaves their home, and provide information regarding efforts each household can take to enact water quality improvements. ICIIII ESTIMATED POLLUTANT LOAD REDUCTION: Other Other BMPs Installed 7SS TPN Sediment ... BOD k 8oretentton kgl,. yr kgfYr' k9 /yr kg /yr k9 /yr s H Pre -Project 287,000 2, 197 13, 114 52, 232 a Post -Project 280, 000 2, 194 12, 922 51, 000 M, Load 2 7, 000 3 192 1, 232 Reduction 0 a. 2% Reduction 2% 1% 1% CMther Other TNT= TSS TP Sedimen# gOp= l r k I r kgrYr kglyr kq yr / kg /yr kg /Yr .': N Pre -Project V M Post -Project M Load Reduction 6 a Reduction th er er TSS t' TN 8. d! mient gOD k I r k I r kg y /r kglyr is kglyr kg /yr kg /yr a Pre -Project cv 5 Post -Project a Load Reduction 5 Reduction Other Other TSS TP TN 3ed nent BOD 70fiAL 0. N Pre -Project M Post- Project Load Reduction 0 a F0/1 Reduction 77. :, Pf MODELMODEL USED:USED: TheThe pollutantpollutant loadload reductionreduction waswas estimatedestimated usingusing thethe SpreadsheetSpreadsheet ToolTool forfor thethe Estimation Estimation ofof ( ( STEPL),STEPL), versionversion 4.4. 1.1. Pollutant Pollutant LoadLoad TheThe estimatedestimated combinedcombined BMPBMP efficiencyefficiency forfor thethe treatmenttreatment train,train, includingincluding thethe proposedproposed sandsand filter,filter, thethe meanderingmeandering vegetated vegetated swale,swale, andand thethe proposedproposed detentiondetention pond,pond, waswas calculatedcalculated usingusing thethe BMPBMP Calculator Calculator includedincluded inin STEPLSTEPL 4.4. 11 andand thenthen enteredentered intointo thethe STEPLSTEPL spreadsheetspreadsheet calculator.calculator. LANDLAND OWNERSHIP OWNERSHIP STATUS:STATUS: 31-31- The property required for the construction of the vegetated swale and the dry detention pond are within existing City Rights of Way. TASK NARRATIVE: Task 1: Construction Plans and Permitting Permitting and construction plans will be developed for the proposed improvements. Plans will meet NPDES, ERP and local permitting requirements and will include plans for wetland plantings. Task 2: Construction After permits have been received, the projects will be bid and construction of the treatment train will be completed. Inspections by City personnel and the Northwest Florida Water Management District will insure that the improvements are built according to plans and specifications and meet permit and grant requirements. Task 3: Public Education CBA and the City will organize an on site education program for the residents located in the contributing area. This program will be developed to inform the residents of the purpose for the construction project, provide information about the Gap Creek Watershed and the path that contributing runoff takes once it leaves their home, and provide information regarding efforts each individual can take to enact water quality improvements. Educational signage will be provided to inform the public about the water quality aspects of wetlands, the value of area water resources, the importance of preventing non -point source pollution, and best management practices for stormwater treatment. Task 4: Monitoring A detailed monitoring plan will be developed and submitted for review after grant award. Base flow and storm event monitoring upstream and downstream of the proposed BMPs will be implemented to demonstrate the effectiveness of these practices at reducing pollutant loads and protecting the downstream water bodies. Task 5: Grant Administration and Reporting This task will include submittal of quarterly and annual reports on project activities. The City will be the lead entity responsible for drafting and submitting the reports. The NWFWMD will provide input and review for all reporting. All reports will be delivered to the FDEP project manager for the 319 grant program. A draft report will be delivered to FDEP for the project describing the construction phase, post - construction monitoring activities and evaluation of the effectiveness of the BMPs. The pollutant efficiency removal measured by the post construction monitoring will be evaluated to determine the effectiveness of the BMPs and qualitative and quantitative water quality impacts to the receiving water bodies including Gap Creek, Cinco Bayou and Choctawhatchee Bay. After review and comment by FDEP, a final project report will be provided. A Quality Assurance Project Plan QAPP) will be submitted and monitoring results will be uploaded to the EPA STORET database or the successor database to STORET 32-  PROJECT MILESTONES /DELIVERABLES: Task Act v Deliverables Start:'; Ga,rriplee :; Contract w/ FDEP signed