Southwest Florida Water Management District Sarasota Bay Surface Water Improvement and Management (SWIM) Plan December 2002 SWIM SECTION RESOURCE MANAGEMENT DEPARTMENT SOUTHWEST FLORIDA WATER MANAGEMENT DISTRICT 7601 U.S. HIGHWAY 301 NORTH TAMPA, FLORIDA 33637 (813) 985-7481 Sarasota Bay Surface Water Improvement and Management (SWIM) Plan Update December 2002 Southwest Florida Water Management District SWIM Section Resource Management Department 7601 U.S. Highway 301 North Tampa, Florida 33637 (813) 985-7481 The Southwest Florida Water Management District (District) does not discriminate upon the basis of any individual's disability status. This nondiscrimination policy involves every aspect of the District's functions, including one's access to, participation, employment, or treatment in its programs or activities. Anyone requiring reasonable accommodation as provided for in the Americans With Disabilities Act should contact the District at 813-985-7481, or 1-800-423-1476 (Florida), extension 2201 ; TDD ONLY 1-800-231-6103 (Florida); FAX 81 3-987-6747 / SunCom FAX 577-6747. 1 TABLE OF CONTENTS TABLE OF CONTENTS ................................................................................... i EXECUTIVE SUMMARY ...................................................................................... 1 INTRODUCTION.............................................................................................. 3 The SWIM Act ........................................................................................3 Sarasota Bay SWIM Plan Evolution.............................................................. 3 Background ...........................................................................................3 Historic Land Use ..............................................................................5 Recent (1990) Land Use .....................................................................5 Sarasota Bay SWIM Plan Process ..............................................................6 Sarasota Bay Management Strategies .........................................................7 Linkages to Other Water Resource Management Activities..................... 9 Internal Linkages ..................................................................9 External Linkages................................................................ 11 PRIORITY PROJECTS..................................................................................... 12 Various Habitat Restoration Projects ..........................................................13 Seagrass Mapping Efforts........................................................................ 14 Status and Trends in Water Quality............................................................ 15 Deployment of Artificial Reefs ...................................................................16 Construction of Oyster Reefs.................................................................... 17 Determination of Nitrogen Sources in Urban Runoff....................................... 18 Water Quality Monitoring in Phillippi Creek ...................................................19 Integrated Water Resource Evaluation....................................................... 20 Evaluation and Implementationof Urban Stormwater Retrofits......................... 21 Update of the Pollutant Loading Model .......................................................22 APPENDIX A .STATUS OF THE 1997 SARASOTA BAY SWIM PLAN...................... 23 Develop a Reuse Master Plan ..................................................................23 Promote Florida Yards and Neighborhoods................................................. 23 Incorporate Water Quality Improvements Into Stormwater Master Plans............. 23 Habitat Restoration ................................................................................24 Seagrass Mapping .................................................................................24 Further Assessment of Atmospheric Deposition ...........................................24 Identification of Toxic Load Sources ...........................................................25 Data Management ..................................................................................25 APPENDIX B .STATUS AND TRENDS IN THE HEALTH OF SARASOTA BAY .........26 Status and Trends in Water Quality ...........................................................26 Contaminant Levels in Bay Sediments .......................................................28 Status and Trends in Wetlands ................................................................29 Status and Trends in Fisheries ................................................................30 Status and Trends in Nitrogen Loads and Seagrass Coverage .........................31 APPENDIX C . LITERATURE CITED ............................................................34 APPENDIX D . GOVERNANCE WITHIN THE SARASOTA BAY BASIN............... 36 APPENDIX E . PERMITTED POINT AND NON-POINT (NPDES) DISCHARGES IN THE SARASOTA BAY BASIN...................... 42 EXECUTIVE SUMMARY Sarasota Bay has a surface water area of approximately 52 square miles, and a contributing watershed of approximately 150 square miles. The watershed is split between Manatee County and Sarasota County, and encompasses the City of Sarasota, as well as the island communities of Anna Maria, Holmes Beach, Bradenton Beach, and Longboat Key. Numerous inlets allow for the exchange of water between the bay and the Gulf of Mexico, including Anna Maria Sound, Longboat Pass, New Pass, Big Pass, and Venice Inlet. Until its closure in 1983, Midnight Pass also was an area of tidal mixing. Due in part to its remarkable natural beauty, Sarasota Bay is an often-cited reason for visitors drawn to the area. Visitors are a vital part of the local economy, as tourism is the number one source of employment in Sarasota County, and the number two source in Manatee County. While the Sarasota Bay region has been inhabited for thousands of years, human degradation of the bay accelerated during the post-World War II years. Between 1950 and 1990, approximately 39 percent of the tidal wetlands were lost to development. Also during this time period, approximately 30 percent of Sarasota Bay's seagrass meadows were lost due to the combined impacts of direct losses due to shoreline development, and indirect losses due to degraded water quality. However, much progress has been made to restore Sarasota Bay in the years since its designation as an "estuary of national significance" by the U.S. Environmental Protection Agency in 1987. With the formation of the Sarasota Bay National Estuary Program (Sarasota Bay NEP) in that year, much attention was focused on developing and implementing a series of projects aimed at restoring and protecting the natural resources of Sarasota Bay. Associated with upgrades to private and public wastewater treatment plants, point-source nitrogen loads to Sarasota Bay have been reduced from 569 tons per year in 1988 to 110 tons per year in 1999, an 81 percent decline. In response, water clarity improved in 7 of 13 bay segments between 1983 and 1998, and only degraded in 1 of 13 bay segments. As water clarity improved, seagrass coverage increased as well, with 596 additional acres found in 1999, as opposed to 1988. In addition to treatment plant upgrades, the Sarasota Bay region now reclaims approximately 46 percent of it wastewater treatment plant effluent for various reuse projects, and numerous stormwater treatment systems have been put in place to further reduce nutrient and toxin loads to the bay. In combination with various local, regional, state and federal agencies, habitat restoration projects in the Sarasota Bay region have enhanced or created approximately 200 acres of fisheries habitat through wetland restoration and removal of exotic vegetation. Additional habitat has been created through the deployment of various types and sizes of artificial 1 Sarasota Bay SWIM Plan December 2002 reefs, ranging from large, complex systems such as that in place offshore of Leffis Key, to small concrete structures designed to fit at the base of various channel markers. An accurate depiction of Sarasota Bay is that of a system that is recovering from its most degraded condition, experienced in the late 19801s,to one that is approaching a much healthier condition. A potential problem, however, is that of continued population growth and development of the bay's watershed. If future growth is not adequately planned for, recent improvements in the health of Sarasota Bay could be offset by the impacts of increased stormwater and wastewater loads, as well as direct human impacts, as more people move to the region. While much progress has been made to improve water quality in both Sarasota Bay and Tampa Bay, most of these improvements have been brought about through the successful management of point sources of pollution. It remains to be seen how effective urban communities can be when attempting to reduce non-point source pollution on a watershed level. The continued implementation of stormwater retrofits of priority tributaries, as well as continued efforts to educate homeowners on the need for creating "bay friendly" landscapes will be required. Additional measures, such as the adoption, by local governments, of more stringent stormwater regulations for new development might be worth considering. The goal, therefore, of this update to the Sarasota Bay SWIM Plan, is to outline a series of research and/or restoration