REGIONAL WATERSHED MANAGEMENT PLANNING FOR METROPOLITAN ATLANTA

The Georgia legislature created the Metropolitan North Georgia Water Planning District (the District) in 2001 to provide comprehensive water resource management plans for storm water/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 area in north Georgia, which includes metropolitan Atlanta.Goals for the watershed management plan (WMP) are 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 water bodies; to support total maximum daily load (TMDL) implementation; to provide water supply protection; to address storm water 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 system (MS4) permitting.Planning efforts included:Characterization of existing watershed conditions and identification of key issues;Development of a water quality model to evaluate existing conditions and future pollutant loads by source;Evaluation of best management practices, source water protection, and TMDL implementation strategies; andDevelopment and evaluation of regional watershed management alternatives.The planning process included significant stakeholder involvement, with nearly monthly meetings with a Technical Coordinating Committee (TCC) comprised of regional public works and utility staff members and Basin Advisory Committees (BACs) comprised of stakeholders with diverse interests from each of the six major 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.Management alternatives were evaluated using a District-wide water quality model (BASINS) that allowed for data output at the 12-digit hydrologic unit code (HUC) level. Nonpoint source control alternatives were integrated with the water supply and wastewater alternatives to determine the most appropriate combination of point and nonpoint source controls to meet the overall goals of the District. The original intent was to be able to evaluate point and nonpoint source balancing within sub-basins for the final plans. However, based on the anticipated growth within the region over the next 30 years, the local governments will need to implement an aggressive storm water management program and high levels of wastewater treatment (for oxygen demanding constituents and nutrients) to maintain or improve water quality to meet current standards.