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

the supporting agencies. A portion of the match is also contributed through the easement acquisition to expand the existing retention pond. 4. RECOMMENDATION: 4. 1 Staff requests City Council approval to submit a FY 2011 Section 319 Grant Proposal Application for the improvement of water quality and flood attenuation of the Gap Creek Watershed to expand an existing retention pond on DRS Technologies, Inc. property at 645 Anchors Street NW. 5. ATTACHMENTS: 5. 1 Section 319 Grant Application 5. 2 Letters of Support from Okaloosa County and Choctawhatchee Basin Alliance 5. 3 Project Drawing 6. SIGNATURE BLOCK: 6. 1 Submitted By: . C`. uol-, Sam Wilson, Stormwater Operations Manager 6. 2 Reviewed and Concur: Michael D. Beedie, P. E. Engineering & Utility Services Director 6. 3 Reviewed and Concur: y fir, Finance Director 6. 4 Reviewed for Agenda: A&jL/ lne& n" l% T. Meares, City Manager 9-  FY2011 SECTION 319 GRANT PROPOSAL APPLICATION PROJECT: GAP CREEK WATERSHED WATER QUALITY IMPROVEMENTS ( PHASE II) PROJECT FUNDING: $ 260, 000 FY2011 319 $ 1831000 Match LEAD ORGANIZATION: City of Fort Walton Beach, Florida CONTACT PERSON: Mr. Michael Beedie, PE Name, Address, Phone) Engineering & Utility Services Director Engineering Services Department City of Fort Walton Beach P. O. Box 4009 Fort Walton Beach, FL 32549 850) 833 -9612 mbeedie @fwb. org COOPERATING ORGANIZATIONS: 1. City of Fort Walton Beach 2. Okaloosa County 3. Northwest Florida Water Management District 4. Choctawhatchee Basin Alliance 5. DRS Technologies, Inc. PROJECT ABSTRACT: The stormwater management system in the Gap Creek Drainage Basin, located in both the City of Fort Walton Beach and in unincorporated Okaloosa County, is inadequate to provide full water quality treatment and flood attenuation. Runoff from portions of the basin receives little or no water quality treatment before discharging downstream into Gap Creek, a tributary to Class III Water Cinco Bayou. A stormwater master plan was prepared for Okaloosa County by HDR Engineering in April 2003; the Gap Creek watershed was modeled and shown to have one of the highest pollutant loading rates in Okaloosa County. In a 2008 cooperative effort, the Northwest Florida Water Management District, Okaloosa County and the City of Fort Walton Beach funded a detailed study of the Gap Creek watershed. The purpose of this study was to identify and prioritize stormwater Best Management Practice ( BMP) opportunities for enhancing treatment and pollutant loading reduction capability. within the Gap Creek watershed. Of the nineteen sites within the Gap Creek watershed recommended for retrofit opportunities that provide pollutant loading reduction, eight also have the potential to reduce flood risk in localized areas of the watershed. The BMP structural improvement chosen for this grant application has the potential to provide both water quality improvement and flood attenuation. The proposed project includes a treatment train comprised of modifying an existing conveyance channel to provide an in line wet detention facility which will provide additional treatment and attenuation. Monitoring will be conducted prior to and after completion of construction at the inflow and outflow of the proposed BMP to determine the system' s effectiveness. The City will design and manage implementation of the improvements, manage the grant and execute all reporting activity. The District will provide technical assistance on the project and assistance and training with water quality monitoring and assessment of BMP effectiveness. CBA will provide public outreach and educational press releases about the project. 10- It is important to note that this project is an integral follow up project to the activities described in the Okaloosa County application submitted in 2009 that was selected for approval. PROJECT LOCATION AND WATERSHED CHARACTERISTICS: Gap Creek is located in the Fort Walton Beach area of Okaloosa County. The creek has two tributaries that originate in the western portion of the drainage area and flow eastward into Cinco Bayou, a Class III water body used heavily as a recreational area. Cinco Bayou is an embayment along the western shoreline Choctawhatchee Bay ( a priority water body of the Northwest Florida Water Management District's SWIM program). The Choctawhatchee Bay has a surface area of approximately 129 square miles. The greatest source of fresh water into the bay is the Choctawhatchee River that flows into the eastern end of the bay. East Pass, located near the western end of the bay immediately west of Destin, is the only direct opening to the Gulf of Mexico. The bay also opens to Santa Rosa Sound at the western most end of the bay and the Intracoastal Waterway on the east end of the bay that winds its way to West Bay ( part of the St. Andrew Bay system). The river and bay system include a diverse array of natural communities. The estuary supports sea grass beds, oyster bars, tidal marshes and unvegetated soft bottom habitats. The Choctawhatchee River and Bay system remains biologically diverse and productive and continues to support a rich ecology and provide an economic, recreational and aesthetic resource for the region. Among the environmental resources are diverse aquatic and wetland habitats, vast forests, Floridan Aquifer springs, steephead streams, and many species of flora and fauna including the endangered Okaloosa darter (Etheostoma oka /oosae). Benefits provided by these natural resources include commercial and recreational fisheries, marine transportation, military uses, outdoor recreation, tourism, aesthetic qualities, and economic benefits associated with all of these activities. In a 2006 study by the Haas Center for Business Research that was commissioned by CBA, it was estimated that the total economic effects in the region related to the Bay include: 36, 030 jobs, 2. 4 billion in gross regional production and 2. 3 billion in personal income. The report also concluded that improved water quality in the Bay will have a direct positive effect on the economy including increased tourist /recreational expenditures as more visitors come to the Bay. While the Choctawhatchee River and Bay watershed continues to support outstanding resources, it has also experienced many of the impacts that are common to Florida estuaries. These include urban stormwater runoff and other nonpoint sources of pollution, widespread sedimentation and habitat loss and degradation. Cumulatively, these impacts have degraded the productivity of the Effective control of nonpoint source river and bay system and diminished the benefits it provides. pollution can help to preserve and restore the natural resources and human benefits provided by the Choctawhatchee River and Bay system and limit the need for more expensive and difficult solutions in the future. Watershed Name: Choctawhatchee Bay Latitude: 30. 4229 Longitude: 86. 6584 Hydrologic Unit Code( HUC): 03140102 Land Uses within the Watershed ( acres and percentages of total): POLLUTION REDUCTION STRATEGY: Okaloosa County completed a Stormwater Master Plan in 2003 to provide a comprehensive evaluation of stormwater infrastructure needs including analysis of water quality and flooding issues. The master plan included a comparative pollutant loading analysis of watersheds for total nitrogen, total phosphorous, total suspended solids and BOD. The analysis showed that the Gap Creek watershed had one of the highest loading rates for these pollutants in Okaloosa County. Based on the analysis of the Stormwater Master Plan, the Gap Creek Watershed Water Quality Improvements study ( November 2008) was funded to identify specific stormwater retrofit alternatives for improving water quality and reduce flooding in the watershed. This application is for one of three retrofit projects that the City of Fort Walton Beach is planning to complete next year. The two remaining projects, Burnette Avenue retrofit and Bay Street retrofit, are proposed in a separate FY2011 -319 funding application. These efforts are directed under the City' s Stormwater Utility which will fund the matching dollars proposed for all of the projects. All of these projects will work in conjunction with the improvements that Okaloosa County proposed in the FY2010 -319 Grant Cycle. Combined the projects will effectively implement recommendations in the Okaloosa Master Stormwater Plan for the Gap Creek watershed to reduce the loading of nonpoint source pollutants into Gap Creek, Cinco Bayou and ultimately Choctawhatchee Bay. This project is also consistent with the 2002 update of Northwest Florida Water Management District' s Surface Water Improvement and Management ( SWIM) Plan for Choctawhatchee River and Bay system. Recommendations in the SWIM plan include the assessment and abatement of non -point source pollution with an emphasis on urban stormwater runoff and implementation of urban BMP demonstration projects that include monitoring to demonstrate the applicability of BMP' s implemented. The specific pollutant load reduction strategy of this project includes retrofitting a straight line, man made conveyance system with the development of an in line wet detention pond. The retrofit will provide treatment for a 78 acre industrial complex in which the majority of the properties do not have adequate treatment or attenuation infrastructure. The capacity of the proposed wet detention facility will provide increased retention time during which strategically located littoral zones planted with native vegetation will allow for nutrient uptake, removal of additional suspended solids and reduction of BOD. The increased capacity of the facility will also provide attenuation to reduce flow rates which will decrease down stream erosion. The littoral zones will be designed and constructed within the facility in a manner to assist in the prevention of short circuiting. The wet pond outlet structure will be designed and constructed with a skimmer that will prevent oil, grease and floating debris from being carried downstream. 12- PROJECT OBJECTIVE( S): Gap Creek flows into Cinco Bayou which is a Class III water body used heavily as a fishing and recreational area. Cinco Bayou outfalls into western Choctawhatchee Bay a SWIM priority waterbody of the Northwest Florida Water Management District' s Surface Water Improvement and Management ( SWIM) program. The bay system has historically been used as a " sink" for point source and nonpoint source pollution. Simultaneously, development has displaced habitat in the watershed and created direct and