GEORGIA STORMWATER MANAGEMENT MANUAL

1 GEORGIA STORMWATERMANAGEMENT MANUALV olume 1: STORMWATER Policy GuidebookFirst Edition August 2001 The development of this MANUAL was facilitated by the Atlanta RegionalCommission. It was funded as a cooperative effort by the following agencies:Atlanta Regional CommissionGeorgia Dept of Natural Resources -- Environmental Protection DivisionCherokee CountyClayton CountyCobb CountyDeKalb CountyDouglas CountyFayette CountyFulton CountyGwinnett CountyHenry CountyRockdale CountyDouglasville/Douglas Co. Water & Sewerage AuthorityAthens-Clarke CountyAugusta-Richmond CountyColumbus-Muscogee CountyCity of AcworthCity of AlbanyCity of AlpharettaCity of AtlantaCity of AustellCity of College ParkCity of DouglasvilleCity of East PointCity of FairburnCity of GriffinCity of HapevilleCity of KennesawCity of Lithia SpringsCity of MariettaCity of PalmettoCity of Peachtree CityCity of Powder SpringsCity of RomeCity of RoswellCity of SmyrnaCity of SnellvilleCity of Union CityThis project was financed in part through a grant from the EnvironmentalProtection

2 Agency under the Provisions of Section 319(h) of the Federal WaterPollution Control Act, as by:AMEC Earth and EnvironmentalCenter for Watershed ProtectionDebo and AssociatesJordan Jones and GouldingAtlanta Regional CommissionVolume 1 (Policy Guidebook) GEORGIA STORMWATER MANAGEMENT MANUAL iTABLE OF ..ixINTRODUCTIONO bjective of the of the of this to Use this Status of the to Get Printed Copies of the to Find the MANUAL on the 1 THE CASE FOR STORMWATER Impacts of Development and STORMWATER Runoff .. Development Changes Land and Changes to Stream Flow.

3 Changes to Stream Impacts to Aquatic Habitat .. Water Quality Impacts .. STORMWATER Effects on Lakes, Reservoirs and Estuaries .. STORMWATER Impacts on GEORGIA Communities .. Addressing Runoff Impacts Through STORMWATER MANAGEMENT ..1-12 CHAPTER 2 REGULATORY REQUIREMENTS FOR GEORGIA Overview .. STORMWATER Quantity and Flooding Prevention Regulations .. National Flood Insurance Program .. GEORGIA Safe Dams Water Quality Regulations .. Municipal NPDES MS4 STORMWATER Permit Industrial NPDES STORMWATER Permit GEORGIA STORMWATER MANAGEMENT ManualVolume 1 (Policy Guidebook) NPDES STORMWATER Permits for Construction Areas.

4 NPDES Municipal Wastewater Discharge Permit Program .. Erosion and Sedimentation Control Act .. Total Maximum Daily Load Program .. GEORGIA Planning Act River Corridor Protection .. GEORGIA Planning Act Water Supply Watersheds .. GEORGIA Planning Act Groundwater Recharge Areas .. Safe Drinking Water Act Wellhead Protection Source Water Assessment Program .. Metropolitan River Protection Wetlands Federal 404 Permits and GEORGIA Planning Coastal MANAGEMENT Program .. Coastal Marshlands Protection Act .. GEORGIA Greenspace Program.

5 2-8 CHAPTER 3 LOCAL STORMWATER MANAGEMENT Overview of Local STORMWATER MANAGEMENT Programs .. Elements of a Comprehensive Local STORMWATER MANAGEMENT Program .. Developing an Effective Local STORMWATER MANAGEMENT Program .. Defining Problems, Program Goals and Requirements .. Determining Program Components and Priorities .. Organizing Program Structure and Funding the Program .. Implementing the 3-15 CHAPTER 4 IMPLEMENTING STORMWATER MANAGEMENT REQUIREMENTS FOR Overview.

6 Minimum Standards for Development .. Minimum STORMWATER MANAGEMENT Standards .. STORMWATER Better Site Design Practices .. Suite of STORMWATER Better Site Design Practices .. Implementing STORMWATER Better Site Unified STORMWATER Sizing Criteria .. Water Channel Protection .. Overbank Flood Protection .. Extreme Flood Protection .. Incorporating the Unified STORMWATER Sizing Criteria into Development Requirements .. 4-16 Volume 2 (Technical Handbook) GEORGIA STORMWATER MANAGEMENT MANUAL STORMWATER Site Design Credits.

7 Introduction .. Site Design Credit #1: Natural Area Conservation .. Site Design Credit #2: Stream Buffers .. Site Design Credit #3: Vegetated Channels ..4-18 Site Design Credit #4: Overland Flow Filtration / Groundwater Recharge Zones .. Site Design Credit #5: Environmentally Sensitive Large Lot Subdivisions .. Implementing STORMWATER Site Design Credits .. Downstream Assessments .. Introduction .. Reasons for Downstream Problems .. Downstream Assessments: The "Ten-Percent" Adopting a Downstream Assessment Guidance on Structural STORMWATER Controls.

8 Introduction .. Recommended Structural STORMWATER Control Practices for GEORGIA Suitability of Structural STORMWATER Controls to Meet STORMWATER MANAGEMENT Implementing Application and Design Criteria for Structural STORMWATER Controls .. STORMWATER MANAGEMENT Site Plans .. Introduction .. Contents of a STORMWATER MANAGEMENT Site Plan .. Procedure for Reviewing STORMWATER Site Plans ..4-28 CHAPTER 5 WATERSHED-BASED STORMWATER STORMWATER Master Planning .. Introduction .. Types of STORMWATER Master Comprehensive Watershed Planning for GEORGIA Communities.

9 Introduction .. Scale of Watershed MANAGEMENT .. The Watershed Planning Process .. Integration of Site and Watershed-Level STORMWATER Planning .. Introduction .. Using the Local Review Process to Comply with Watershed Plans .. Inter-jurisdictional Watershed Planning .. Implementation of Watershed Plans .. Introduction .. Tools of Watershed MANAGEMENT and Stakeholder Involvement Cost (Budget) .. Performance Monitoring and Assessment ..5-19iv GEORGIA STORMWATER MANAGEMENT ManualVolume 1 (Policy Guidebook) Regional vs.

10 On-site STORMWATER MANAGEMENT .. Advantages and Disadvantages of Regional STORMWATER Important Considerations for the Use of Regional STORMWATER 5-21 CHAPTER 6 FLOODPLAIN Local Floodplain MANAGEMENT and STORMWATER Floodplain MANAGEMENT Goals .. National Flood Insurance Program .. Background .. NFIP Program Shortcomings of the Strategies and Tools for Improved Floodplain MANAGEMENT .. Developing an Effective Local Floodplain MANAGEMENT Watershed / Inter-jurisdictional Issues.