INTEGRATION OF TMDL IMPLEMENTATION INTO REGIONAL WATERSHED MANAGEMENT PLANNING

The metropolitan Atlanta area has experienced tremendous growth over the last 10 years and the associated increases in urban area have resulted in water quality violations, with 55 percent of the streams not meeting designated use and over 1,000 miles of streams listed for Total Maximum Daily Loads (TMDLs). In addition, Region IV of the Environmental Protection Agency and the Georgia Environmental Protection Division (GAEDP) were sued over TMDL development in Georgia, resulting in the State having to meet an accelerated schedule for TMDL implementation. To address these water quality issues, and related water and wastewater capacity needs, Georgia created the Metropolitan North Georgia Water Planning District (the District) in 2001. The District was developed to provide comprehensive water resource management plans for stormwater/watershed management, water supply, and wastewater. Integration of these three plans was designed to address the need for regional cooperation on water resource management within a 16-county metropolitan area.Major goals of the watershed management plan (WMP) were to develop a comprehensive and integrated 30-year regional plan to help the 16-county region meet water quality standards and remove streams from the 303(d) list of impaired waterbodies, to support TMDL implementation, to provide water supply protection, to address stormwater-related hydrologic changes and reduce downstream flooding, to improve aquatic habitat and biotic integrity, and to help local governments meet the requirements for municipal separate storm sewer (MS4) permitting. Planning efforts included:Characterization of existing watershed conditions and identification of key issuesDevelopment of a water quality model to evaluate existing conditions and future pollutant loads by sourceEvaluation of best management practices (BMPs), source water protection, and TMDL implementation strategies, andDevelopment and evaluation of regional watershed management alternativesThe planning process included significant stakeholder involvement, such as nearly monthly meetings with a Technical Coordinating Committee (TCC) comprised of regional public works and utility staff members and Basin Advisory Councils (BACs) comprised of a diverse group of stakeholders from each of the six watersheds within the District. A stepwise process was used with the stakeholder committees to develop the WMP with incremental technical evaluations building to the final recommended District-wide plan.Within the District, the primary causes (contributing to 99 percent of the violations) of impairment listed by the GAEPD are urban and nonpoint source runoff. Therefore, the recommendations for TMDL implementation focused on development and implementation of regionally consistent stormwater and watershed management programs. General recommendations included implementation of:Programmatic Watershed Measures –a comprehensive suite of stormwater management measures that all local governments within the District will be required to implement.Watershed Improvement Measures –measures focused on watersheds that are currently highly developed and are substantially impacted. Local governments would be required to develop watershed improvement plans to improve existing conditions to meet designated uses.In addition, the recommendations for TMDL implementation strategies focused on closer interjurisdictional coordination between local governments. Watersheds for many of the impaired streams include more than one county or municipal government's boundaries and successful implementation of the recommended TMDL program will require cross-jurisdictional cooperation. A process for inter-jurisdictional cooperation was recommended in the WMP.Implementation of these measures will address the primary stormwater management requirements as new development continues and, over time, will provide significant improvement in impaired watersheds. The combination of these District-wide watershed management measures and local, stream segment-specific TMDL implementation steps will provide consistent management strategies for TMDLs within the District.