CITY OF GRANDVIEW GENERAL SEWER PLAN Prepared by PROJECT NO. 08032 January 2009 CITY OF GRANDVIEW GENERAL SEWER PLAN Prepared by PROJECT NO. 08032 January 2009 TABLE OF CONTENTS Page No. INTRODUCTION AND EXECUTIVE SUMMARY ......................................................................................... 1 INTRODUCTION ............................................................................................................................... 2 REQUIREMENTS.............................................................................................................................. 2 PURPOSE AND OBJECTIVE OF PLAN ........................................................................................... 2 SUMMARY OF RECOMMENDED IMPROVEMENTS ...................................................................... 3 SCHEDULE OF IMPROVEMENTS ................................................................................................... 3 ESTIMATED COSTS AND PROPOSED SEWER SYSTEM FINANCIAL PROGRAM ..................... 3 CHAPTER 1 - BASIC PLANNING INFORMATION ...................................................................................... 4 1.1 BACKGROUND INFORMATION .............................................................................................. 5 Wastewater System Ownership .......................................................................................... 5 Geography ........................................................................................................................... 5 Wastewater System History ................................................................................................ 8 1.2 RELATED PLANNING DOCUMENTS ...................................................................................... 9 Wastewater Plans ............................................................................................................... 9 Wastewater Treatment Facilities Engineering Report ......................................................... 9 Other Reports and Documents ........................................................................................... 9 Urban Growth Area Comprehensive Plan ......................................................................... 10 Comprehensive Water Plans ............................................................................................ 10 1.3 NEIGHBORING/ADJACENT WASTEWATER SYSTEMS ..................................................... 10 1.4 EXISTING SERVICE AREA .................................................................................................... 11 1.5 FUTURE SERVICE AREA ...................................................................................................... 13 Land Use ........................................................................................................................... 13 1.6 POPULATION ......................................................................................................................... 16 Current Population ............................................................................................................ 16 Future Population .............................................................................................................. 17 CHAPTER 2 - PAST AND PROJECTED WASTEWATER LOADINGS FORECASTING .......................... 18 2.1 PREVIOUS INFLUENT WASTEWATER TRENDS ................................................................ 19 Background ....................................................................................................................... 19 System Capacity ............................................................................................................... 19 Influent Flow Loadings - Entire Facility .............................................................................. 20 Influent Flow Loadings - Mechanical Wastewater Treatment Plant .................................. 21 Industrial Flows ................................................................................................................. 21 Influent Biochemical Oxygen Demand (BOD5) Loading - Entire Facility ........................... 23 Influent Biochemical Oxygen Demand (BOD5) Loadings - Mechanical WWTP ................ 23 Industrial Biochemical Oxygen Demand (BOD5) Loadings ............................................... 24 Influent Total Suspended Solids (TSS) Loadings - Entire Facility ..................................... 26 Influent Total Suspended Solids (TSS) Loadings - Mechanical WWTP ........................... 26 Industrial Total Suspended Solids (TSS) Loadings ........................................................... 27 2.2 FUTURE WASTEWATER LOADING PROJECTIONS ........................................................... 29 CHAPTER 3 - EXISTING COLLECTION SYSTEM .................................................................................... 30 3.1 GENERAL DESCRIPTION ...................................................................................................... 31 3.2 COLLECTION SYSTEM BASINS............................................................................................ 31 3.3 LIFT STATIONS ...................................................................................................................... 35 3.4 EXISTING SEWER SYSTEM HYDRAULIC ANALYSIS ......................................................... 37 Unit Flow Rates ................................................................................................................. 38 Collection System Hydraulic Analysis Results……………………………….. 39 Lift Stations Hydraulic Analysis Results ............................................................................ 40 Force Main Hydraulic Analysis Results ............................................................................. 40 3.5 COLLECTION SYSTEM MAINTENANCE PROBLEMS ......................................................... 41 3.6 COLLECTION SYSTEM INFILTRATION / INFLOW ............................................................... 43 Infiltration ........................................................................................................................... 43 Inflow ................................................................................................................................. 44 Infiltration / Inflow Conclusions .......................................................................................... 46 CHAPTER 4 - FUTURE COLLECTION SYSTEM ...................................................................................... 47 4.1 GENERAL DESCRIPTION ...................................................................................................... 48 4.2 FUTURE COLLECTION SYSTEM BASINS ............................................................................ 48 4.3 FUTURE SEWER SYSTEM HYDRAULIC ANALYSIS ........................................................... 54 Unit Flow Rates ................................................................................................................. 56 Collection System Hydraulic Analysis Results .................................................................. 56 Lift Stations Hydraulic Analysis Results ............................................................................ 59 Force Mains Hydraulic Analysis Results ........................................................................... 60 CHAPTER 5 - YEAR 2028 COLLECTION SYSTEM .................................................................................. 61 5.1 GENERAL DESCRIPTION ...................................................................................................... 62 5.2 YEAR 2028 COLLECTION SYSTEM BASINS ........................................................................ 62 5.3 FUTURE SEWER SYSTEM HYDRAULIC ANALYSIS ........................................................... 67 Unit Flow Rates ................................................................................................................. 67 Collection System Hydraulic Analysis Results .................................................................. 68 Lift Stations Hydraulic Analysis Results ............................................................................ 68 Force Mains Hydraulic Analysis Results ........................................................................... 68 CHAPTER 6 - TREATMENT AND DISPOSAL FACILITIES ....................................................................... 70 6.1 EXISTING WASTEWATER TREATMENT FACILITIES ......................................................... 71 Mechanical Treatment Process......................................................................................... 72 Lagoon Treatment Process ............................................................................................... 74 6.2 BIOSOLIDS PROCESSING FACILITIES ................................................................................ 76 6.3 PERMIT EFFLUENT LIMITS AND EFFLUENT QUALITY ...................................................... 81 Effluent Quality - Yakima River Discharge ........................................................................ 82 Effluent Quality - City Sprayfield Discharge ....................................................................... 85 Effluent Quality - Non-Overflow Pond System .................................................................. 85 6.4 FUTURE WASTEWATER LOADING PROJECTIONS ........................................................... 85