CITY OF MILTON PIERCE/KING COUNTY, WASHINGTON WATER SYSTEM PLAN

Transcription

1 CITY OF MILTON PIERCE/KING COUNTY, WASHINGTON WATER SYSTEM PLAN G&O #08474 July 2010

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6 EXECUTIVE SUMMARY TABLE OF CONTENTS CHAPTER 1 DESCRIPTION OF THE WATER SYSTEM INTRODUCTION SYSTEM OWNERSHIP AND MANAGEMENT SYSTEM BACKGROUND History Retail Service Area Climate Geography/Geology Land Use and Zoning Future Land Use Adjacent Purveyors INVENTORY OF EXISTING FACILITIES Source of Supply Water Rights Intertie Agreements Water Treatment Facilities Pressure Zones Storage Pumping Facilities th Avenue Booster Station (434 Zone) MG Reservoir Booster Station (520 Zone) MG Reservoir Booster Station (520 Zone) Transmission and Distribution System Meters SCADA System Pressure Reducing Valves RELATED PLANNING DOCUMENTS City of Milton Water System Plan (2003) City of Milton Comprehensive Plan (2002) Pierce County Coordinated Water System Plan (CWSP) (2001) SERVICE AREA POLICIES Applications for New Service Wholesaling and Wheeling Water Direct Connection and Remote System Design and Performance Standards Surcharge for Outside Customers Latecomer Agreements Cross-Connection Control Program Extension Connection Fee i

7 Urban Growth Area CHAPTER 2 BASIC PLANNING DATA EXISTING POPULATION, SERVICES, AND WATER DEMAND Residential Population Total Service Connections Water Production Consumption History Distribution System Leakage Equivalent Residential Units Peaking Factors Peak Day Factor Peak Hour Factor Population Projections Water Production Projections CHAPTER 3 SYSTEM ANALYSIS INTRODUCTION SYSTEM DESIGN STANDARDS General Facility Standards Water Quality Standards Water System Design Standards General Facility Standards Fire Flow Standards Water Quality Standards Applicable Drinking Water Quality Regulations Water Quality Standards and Analysis Bacteriological Inorganic Physical and Chemical Characteristics Volatile Organic Compounds (VOCs) and Synthetic Organic Compounds (SOCs) Lead and Copper Radionuclides and Radon Disinfectants/Disinfection Byproducts (D/DPB) Arsenic Rule Asbestos Residual Disinfectant Water Quality Monitoring Schedule Conclusion WATER RIGHTS ANALYSIS SOURCE OF SUPPLY ANALYSIS TREATMENT STORAGE ANALYSIS Operational Storage Equalizing Storage ii

8 Standby Storage Fire Suppression Storage Dead Storage BOOSTER STATION ANALYSIS DISTRIBUTION SYSTEM ANALYSIS WATER SYSTEM RELIABILITY ANALYSIS Facility Reliability Source Reliability Treatment Storage Booster Stations CHAPTER 4 HYDRAULIC ANALYSIS HYDRAULIC MODELING PROGRAM MODEL LAYOUT AND CONSTRUCTION Source Storage Pressure Reducing Valves Model Demands Scenarios Model Calibration Existing System Analysis and Results Peak Hour Demand Available Fire Flows Deficiencies CHAPTER 5 WATER USE EFFICIENCY PROGRAM WATER USE EFFICIENCY PLANNING REQUIREMENTS PAST CONSERVATION PROGRAMS Effects of Past Programs PLANNING REQUIREMENTS Data Collection and Reporting Demand Forecast Source Evaluation WUE Measures DISTRIBUTION SYSTEM LEAKAGE GOAL SETTING AND WUE MEASURES Goals Evaluation or Implementation of WUE Measures Mandatory Measures Supplementary Measures Target Water Savings Projections PERFORMANCE REPORTING iii

9 CHAPTER 6 WELLHEAD PROTECTION PROGRAM INTRODUCTION Susceptibility Assessment CHAPTER 7 OPERATION AND MAINTENANCE PROGRAM WATER SYSTEM MANAGEMENT AND PERSONNEL CERTIFICATION REQUIREMENTS Professional Growth Requirements SYSTEM OPERATION AND CONTROL Major System Components Source of Supply Water Treatment Reservoirs Transmission and Distribution Booster Pump and Pressure Reducing Valve Stations Telemetry Preventive Maintenance Program Wells and Treatment Plant Reservoir Distribution System Valve and Hydrant Maintenance Distribution System Flushing Program Booster Pump Stations Meters Inventory of Materials Recommended Schedule EMERGENCY RESPONSE PROGRAM Water System Personnel Emergency Call-Up List Emergency Procedures Contamination of Water Supply Bacteriological Presence Detection Procedure VOC/SOC and Inorganic Chemical/Physical Characteristics Detection Procedures Power Failure Severe Earthquake Major Fire Cold Weather Conditions Distribution System Low/High Pressure CROSS-CONNECTION CONTROL PROGRAM Priority Service List New and Existing Cross-Connection Devices Cross-Connection Control Program Record Keeping iv

10 CHAPTER 8 CAPITAL IMPROVEMENT PLAN INTRODUCTION Water Supply Projects WS-1: Corridor Wells Iron and Manganese Treatment ( ) WS-2: Phase 1 Additional Source: Exploratory Drilling and Land Acquisition ( ) WS-3: Phase 2 Additional Source: Equipping (2015) Storage Projects ST-1: 15 th Avenue Reservoir Painting (2011) Booster Station Projects BS-1: Lloyd s Development Booster Station (2010) BS-2: 15 th Avenue Booster Station (2011) BS-3: 1-MG Reservoir Booster Station(2011) Pressure Zone Modification Projects PZ-1: Goat Hill Pressure Zone Change (2013) Distribution System Projects Project D-1: Meridian Avenue East (2010) Project D-2: School Property South Connection and Looping (2014) Project D-3: Birch Street Crossing (2014) Project D-4: Porter Way Crossing (Beyond 2015) Project D-5: 2-MG Reservoir Booster Station to Northwood Elementary (Beyond 2015) Project D-6: 2-MG Reservoir Booster Station to Northwood Elementary (Beyond 2015) Project D-7: 11 th Avenue from Juniper Street to Fir Street (Beyond 2015) Project D-8: Hemlock Street (Beyond 2015) Project D-9: Porter Way from Taylor Street to Milton Way (Beyond 2015) Project D-10: Reconnection of Services Along 15 th Avenue (Beyond 2015) Project D-11: 12 th Avenue (Beyond 2015) Project D-12: 13 th Avenue North of Taylor Street (Beyond 2015) Project D-13: 19 th Avenue (Beyond 2015) Project D-14: 15 th Avenue (Beyond 2015) Project D-15: Yuma Street (Beyond 2015) Project D-16: 13 th Avenue South of Emerald Street (Beyond 2015) Project D-17: Xavier Street (Beyond 2015) Project D-18: 13 th Avenue and Comet Street (Beyond 2015) Project D-19: Diamond Street (Beyond 2015) Project D-20: 22 nd Avenue Court to Alder Street (Beyond 2015) Project D-21: Milton Way and 13 th Avenue (Beyond 2015) Project D-22: 70 th Avenue East (Beyond 2015) Project D-23: Comet Street (Beyond 2015) v

11 Project D-24: Millridge Village Apartments (Beyond 2015) Project D-25: Diamond Loop (Beyond 2015) Project D-26: Dead-End Pipe Near Queens Way (Beyond 2015) Miscellaneous Projects M-1: Service Meter Replacement Program ( ) M-2: Site Security (2010) M-3: Well No. 10 Building Upgrades/Retrofitting (Beyond 2015) Summary of Recommended Improvements CHAPTER 9 FINANCIAL ANALYSIS FINANCIAL STATUS OF EXISTING WATER UTILITY Current Water Rates Current Connection Fees HISTORICAL FINANCIAL OPERATIONS PROJECTED GROWTH PROJECTED EXPENSES, REVENUES, AND CAPITAL Future Operating Expenses and Revenues Future Capital Expenditures and Revenues CAPITAL IMPROVEMENTS AND FINANCING AVAILABLE CAPITAL PROJECT FUNDING SOURCES Public Works Trust Fund Drinking Water State Revolving Fund Community Economic Revitalization Board (CERB) Revenue Bonds RECOMMENDATION vi

12 LIST OF TABLES No. Table Page E-1 Monthly Water Base Rates... E-2 E-2 Monthly Usage Rates... E-3 E-3 Capital Improvement Plan... E City Zoning Classifications Well Summaries Water Rights Reservoirs th Avenue Booster Station Pump Characteristics MG Reservoir Booster Station Pump Characteristics MG Reservoir Booster Station Pump Characteristics Pipe Inventory PRV Stations Historic Retail Service Area Population Service Connections Metered Water Production Monthly Water Production by Source (MG) Historic Water Production Per Capita Annual Consumption by Customer Class (Gallons per Day) Annual Consumption by Customer Class as a Percentage of Total Seasonal Variation by Customer Class for Calculated Distribution System Leakage Equivalent Residential Units for Equivalent Residential Units for Top Ten Highest Users for Peak Day Production Projected Population for Water Service Area Projected Demands Through General Facility Requirements Summary of Drinking Water Regulations Water Quality Standards for Inorganic Chemical Characteristics Water Quality Standards for Inorganic Physical Characteristics Regulated VOCs and SOCs Lead and Copper Testing Radionuclide MCLs Water Quality Monitoring Summary Instantaneous Water Rights Analysis Annual Water Rights Analysis Source of Supply Storage Analysis th Avenue Booster Station Open System MG and 2-MG Booster Stations Closed System vii

13 No. Table Page 4-1 Modeled Reservoir Depleted Volumes and Drawdown Levels Population and Demand Forecasts Calibration Node Numbers and Locations Hydraulic Model Calibration Results General Fire Flow Requirements Available Fire Flows Summary of Water Use Data Collection Demand Forecast Distribution System Leakage Summary ERU Reduction Goal Summary Water Use Efficiency Measures Projected Water Use Efficiency Savings Susceptibility Ratings Active Well Characteristics Reservoirs Well and Treatment Plant Task List Reservoir Task Lists Booster Pump Station Task Lists Preventive Maintenance Schedule Water System Emergency Phone List Water Contamination Response Bacteriological Presence Detection Procedures Severe Earthquake Response Distribution System High/Low Pressure Response Year Capital Improvement Plan Monthly Water Base Rates Monthly Water Volume Charges System Development Charges Historical Financial Operations Projected Water Utility Revenues, Projected Water Utility Expenses, Projected Water Utility Revenues and Expenses Summary, Capital Improvements for the Years 2009 Through viii

14 LIST OF FIGURES No. Figure On or Follows Page 1-1 Location Map City Limits, Retail Service Area and Urban Growth Area Topographic Map Zoning Adjacent Purveyors Water System Water System Schematic SCADA Schematic Total Connections Available Fire Flow Available Fire Flow with CIPs Distribution System Leakage Summary Volatile Organic, Synthetic Organic, and Inorganic Chemical Detection Procedure Capital Improvement Project LIST OF APPENDICES Appendix A WSP Submittal Forms and Checklist Appendix B Water Facilities Inventory Form Appendix C Interlocal Agreements and Service Area Documents Appendix D Water Rights, Water Rights Self-Assessment Appendix E Intertie Agreements Appendix F Local Government Consistency Review Checklists and Comments Appendix G Municipal Code Appendix H Water Service Documents Appendix I Design Standards Appendix J Water Quality Documents Appendix K Hydraulic Modeling Results Appendix L Water Use Efficiency Documents Appendix M Wellhead Protection Plan Appendix N Well Susceptibility Appendix O Maintenance Forms Appendix P Cross-Connection Control Plan Appendix Q CIP Cost Estimates Appendix R Water Source and Hydrogeologic Analysis Technical Memorandum Appendix S Low Pressure Study Appendix T Correspondence ix

15 EXECUTIVE SUMMARY The City of Milton Water System Plan provides a planning strategy for the City s water utility over 6- and 20-year periods. The plan has been prepared consistent with Department of Health requirements as specified in the Washington Administrative Code (WAC) Chapter The plan represents a commitment by the City to pursue and implement the Plan s recommendations and capital improvements. Chapters 1 and 2 of this Plan provide background data, including a description of existing facilities, service area, service area policies, and projections of population and water use. Chapter 3 presents a description of system design and water quality standards, and an analysis of water quality. This chapter also presents a source and storage analysis. Chapter 4 is a distribution system analysis which includes hydraulic modeling summary and the basis for identification of distribution system improvements. Chapter 5 is a water use efficiency program which details conservation and efficient water use goals and measures. Chapter 6 discusses and augments the City s Wellhead Protection Plan. Chapter 7 discusses the system operation and maintenance procedures. Chapter 8 presents the recommended capital improvements and Chapter 9 presents financing for the recommended improvements. The nine chapters of this report are followed by appendices which contain backup documentation. The City utilizes groundwater for its supply of water. These groundwater sources include six active wells and one emergency well throughout the City. These wells are labeled Well Nos. 3, 5, 7, 10, 12 and Corridor 1 and 2. Well Nos. 3, 7, 10 and 12 are located in the lower zone and are subject to corrosion control measures at the Public Works Shop through sodium hydroxide addition. The Corridor Wells are also located in the lower zone, and receive corrosion control through aeration on site. The wells pump to the lower zone where the 15 th Avenue Booster Station delivers water into the City s middle zone. Well No. 5 is located at the City s 1.0-MG Reservoir and is pumped into the middle and upper zones of the service area. The City s water retail service area population is approximately 7,868 people. The water system serves a total of 2,648 connections. The City anticipates growth of approximately 1 percent in 2009, 2 percent per year in 2010 and 2011, and 3 percent per year in 2012 and beyond. Build-out is expected to occur in 2025 with a population of 12,371. The City has enough water rights available to provide the necessary amount of water to its current customers and future projected population. However, the City is not able to fully utilize these rights due to aquifer constraints. Combined current output of the City s wells is 2,020 gpm. Wells are operated at or near production limits based on aquifer capacity. Maximum day demands are projected to exceed well and aquifer capacity in The City will need to develop additional source capacity before this time. For emergency supply, the City has interties with the Mt. View-Edgewood Water Company and Lakehaven Utility District to augment system flows, if necessary. City of Milton E-1 Water System Plan July 2010

16 Gray & Osborne, Inc., Consulting Engineers Currently, the City s water system is in compliance with all applicable regulatory requirements. Following the recommendations of this plan will insure continued compliance. The City s operation and maintenance staff are dedicated to providing the best possible operations of the City s water system and to keeping the system in compliance with all regulations. The Water System Plan contains a list of projects for the City s 6-year capital improvement plan for the water system. These projects include improving and developing sources, upgrading booster stations, replacing meters, and replacing water mains throughout the system to provide increased reliability, better water quality, and the increased fire flow capabilities to the system. The City increased rates in 2009 to help maintain reserve funds. Revenue from water sales and connection charges are not adequate to fund the recommended projects however, and the City will need to explore alternative funding options or project schedules. Tables E-1 and E-2 provide a summary of the existing water rates. TABLE E-1 Monthly Water Base Rates Meter Size Base Rate 3/4 inch or less $ inch $ /4 inch $ /2 inch $ inch $ inch $ inch $ inch $ Senior/Disability 30% Discount $15.43 Fire Protection Line $26.27 E-2 City of Milton July 2010 Water System Plan

17 Gray & Osborne, Inc., Consulting Engineers TABLE E-2 Monthly Usage Rates Mutli-family, Commercial, Volume Charge Single-Family and Duplex Cost/ccf Institutions, Government Cost/ccf 0 to 800 cf/mo $2.41 $ to 1,000 cf/mo $2.61 $2.73 1,001 to 2,000 cf/mo $2.81 $2.93 2,001 to 3,000 cf/mo $2.81 $3.13 > 3,000 cf/mo $2.81 $3.33 Table E-3 provides the list of recommended capital improvement projects within the 6-year planning horizon. TABLE E-3 Capital Improvement Plan Project Description Project Year 2009 Cost (1) Corridor Wells Iron and Manganese Treatment WS $ 655,000 Lloyd's Development Booster Station BS Developer Meridian Ave E D $ 80,000 Service Meter Replacement Program M $ 100,000 Site Security M $ 25, Total $ 860,000 15th Avenue Reservoir Coating ST $ 190,000 15th Avenue Booster Station BS $ 220,000 Service Meter Replacement Program M $ 100, Total $ 510,000 1 MG Reservoir Booster Station BS $ 400,000 Service Meter Replacement Program M $ 100, Total $ 500,000 Birch Street Crossing D $ 325, Total $ 325,000 Birch Street Crossing D $ 325, Total $ 325,000 Goat Hill Pressure Zone Change PZ $ 105, Total $ 105,000 TOTAL $ 2,625,000 (1) Capital Improvement costs from Table 8-1. (2) Capital improvement costs from Chapter 8 have been adjusted 3 percent annually for inflation based on the year the project is estimated to begin construction. City of Milton E-3 Water System Plan July 2010