WATER RESOURCE MANAGEMENT PLAN Prepared by DRAFT July 2016 Contents 1 Introduction ......................................................................................................................... 1-1 1.1 Metropolitan North Georgia Water Planning District Overview ..................................... 1-1 1.2 Integrated Regional Water Resource Planning ................................................................ 1-5 1.3 Plan Update Focus ........................................................................................................... 1-6 1.4 Key Changes in the Plan ................................................................................................... 1-7 1.5 Developing the Plan ......................................................................................................... 1-7 1.5.1 Policy Goals ......................................................................................................... 1-8 1.5.2 Planning Context ................................................................................................. 1-9 1.5.3 Plan Coordination ............................................................................................... 1-9 1.6 Implementing the Plan and Measuring Progress ........................................................... 1-12 2 Planning Principles and Management Challenges ................................................................. 2-1 2.1 Planning Principles for the 2017 Plan Update ................................................................. 2-1 2.2 Continuing and Emerging Management Challenges ....................................................... 2-3 3 Existing Facilities and Conditions ......................................................................................... 3-1 3.1 Population ........................................................................................................................ 3-1 3.2 Water Supply and Treatment .......................................................................................... 3-1 3.2.1 Surface Water Supplies ....................................................................................... 3-2 3.2.2 Groundwater Supplies ........................................................................................ 3-6 3.2.3 Existing Water Treatment Facilities .................................................................... 3-7 3.2.4 Non-municipal Permitted Withdrawals .............................................................. 3-9 3.2.5 Water Conservation .......................................................................................... 3-10 3.2.6 Existing Interconnections .................................................................................. 3-11 3.3 Wastewater Generation and Treatment ....................................................................... 3-12 3.3.1 Existing Public Wastewater Treatment Facilities .............................................. 3-12 3.3.2 Non-Municipal Permitted Wastewater Facilities .............................................. 3-17 3.3.3 Existing Septic System Use ................................................................................ 3-18 3.4 Basin Return Flow Conditions ........................................................................................ 3-19 3.4.1 Assumptions Regarding Septic and LAS returns ............................................... 3-19 3.4.2 Reclaimed Water Reuse .................................................................................... 3-20 3.4.3 Existing Interbasin Transfers ............................................................................. 3-22 3.4.4 Net Water Use .................................................................................................. 3-23 3.5 Watershed Development ............................................................................................... 3-23 3.6 Drinking Water Supply Watersheds ............................................................................... 3-29 3.7 Instream Conditions ....................................................................................................... 3-31 3.7.1 Surface Water Quality ....................................................................................... 3-31 3.7.2 Protected Aquatic Species ................................................................................ 3-32 4 Future Conditions ................................................................................................................. 4-1 4.1 Population and Employment Projections ........................................................................ 4-1 4.2 Water Demand Forecasts ................................................................................................ 4-4 WATER RESOURCE MANAGEMENT PLAN PAGE I METROPOLITAN NORTH GEORGIA WATER PLANNING DISTRICT JULY 2016 WT0404161132ATL CONTENTS 4.2.1 Methods .............................................................................................................. 4-4 4.2.2 Water Demand Forecasts with Enhanced Efficiency Standards and Uncertainty Analysis ......................................................................................... 4-16 4.3 Wastewater Forecasts ................................................................................................... 4-18 4.3.1 Methods ............................................................................................................ 4-18 4.3.2 Septic System Use Forecasts ............................................................................. 4-20 4.3.3 Wastewater Flows Forecasts ............................................................................ 4-20 4.3.4 Septic System Impact to Wastewater Treatment Facilities .............................. 4-22 4.4 Watershed Land Use Projections ................................................................................... 4-22 Tables 1-1 Local Jurisdictions of the Metropolitan North Georgia Water Planning District 2-1 Continuing and Emerging Management Challenges 3-1 Existing Permitted Surface Water Supply Withdrawals in the District 3-2 Existing Permitted Groundwater Withdrawals (Non-Farm) for Public Water Supply in the District 3-3 Existing Surface Water Treatment Plants in the District 3-4 Non-municipal Surface Water Permitted Withdrawals in the District – Excluding Power Generation Sector 3-5 Water Conservation Measures Implemented in the District, Based on Requirements in the 2003 Plan, 2009 Plan Update and 2010 Plan Amendments 3-6 Municipal Permitted Wastewater Treatment Capacity in the District by River Basin 3-7 Municipal Permitted Wastewater Treatment Capacity in the District by County 3-8 Existing Permitted Wastewater Treatment Facilities in the District 3-9 Total Non-Municipal Permitted Wastewater Treatment Capacity in the District by River Basin 3-10 Estimated Number of Existing Septic Systems in the District by County (2013) 3-11 Examples of Non-potable and Planned Indirect Potable Reuse in the District 3-12 Summary of Interbasin Water Transfers for 2013 3-13 Net Water Use in the District 3-14 Land Use in the District: 2010 3-15 Impaired Stream Miles in the District (2014) 3-16 Impaired Streams in the District by Water Quality Parameter (2014) 4-1 Population Projections by County 4-2 Employment Projections by County 4-3 Municipal Water Demand Baseline per County (AAD-MGD) 4-4 Baseline Water Use Profile by County (GPCPD) 4-5 National Average Single Family Indoor Water End Uses – Water Research Foundation 4-6 Current Plumbing and Appliance Standards and Estimates of Natural Rate of Plumbing Fixture and Appliance Conversion 4-7 Water Demand Forecasts for the District with Enhanced Efficiency Standards and Uncertainty through 2050 4-8 Forecasted Septic System Flows by County (AAD-MGD) 4-9 Wastewater Flow Forecasts for Centralized Wastewater Treatment Facilities (AAD) 4-10 Wastewater Flow Forecasts for Centralized Wastewater Treatment Facilities (MMF-MGD) PAGE II WATER RESOURCE MANAGEMENT PLAN JULY 2016 METROPOLITAN NORTH GEORGIA WATER PLANNING DISTRICT WT0404161132ATL CONTENTS Figures 1-1 Metropolitan North Georgia Water Planning District 1-2 Metropolitan North Georgia Water Planning District: Major River Basins 1-3 Metropolitan North Georgia Water Planning District: Major River Basins 1-4 Policy Goals for the Plan Update 1-5 Georgia Water Planning Regions 1-6 Plan Development and Implementation 3-1 District Population: 1970-2014 3-2 District Per Capita Water Use Trend 2000-2013 3-3 Non-Municipal Wastewater Facilities in the District - Permitted Capacity Distribution by Sector 3-4 Estimated Percent of Single Family Residences with Septic Systems and Baseline Septic Flows in the District 3-5 Permitted Capacity Distribution of Treated Wastewater Flows in the District (2015) 3-6 Changes in Runoff and Hydrology Due to Development 3-7 Land Cover in the District, 1974 and 2011 3-8 Land Use in the District: 2012 3-9 Source Water Supply Watersheds for the District 4-1 DSS Model Overview 4-2 Water System Diagram 4-3 Water Use Profile, District Baseline 4-4 County-Level Water Use Profiles, District Baseline 4-5 Single Family End Uses, District Baseline 4-6 Toilet Fixture Estimates by County, District Baseline 4-7 Comparison of Water Demand Forecasts for the District 4-8 Wastewater Flow Calculation 4-9 Projected 2040 Land Use in Metropolitan Atlanta Region 4-10 Projected 2040 Land Use for the District by River Basin WATER RESOURCE MANAGEMENT PLAN PAGE III METROPOLITAN NORTH GEORGIA WATER PLANNING