Water System Plan
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City of Ocean Shores CITY OF OCEAN SHORES WATER SYSTEM PLAN SYSTEM WATER CITY OF OCEAN SHORES WATER SYSTEM PLAN Prepared By: Prepared By: CITY OF OCEAN SHORES WATER SYSTEM PLAN Prepared for: City of Ocean Shores 710 Point Brown Avenue N.W. Ocean Shores, WA 98569 Prepared by: PACE Engineers, Inc. 11255 Kirkland Way, Suite 300 PROJECT CERTIFICATION The technical material and data contained in this Water System Plan was prepared by PACE Engineers, Inc. under the supervision of the below listed individuals. Those responsible staff members who are registered professional engineers are licensed in the State of Washington. Susan E. Boyd Vice President, Project Principal William Reynolds, P.E. Principal Engineer Page i This Page Intentionally Blank Executive Summary This Comprehensive Plan is a compilation of planning and engineering studies completed by PACE Engineers, Inc. The purpose of this Plan is to evaluate the City of Ocean Shores water system for its ability to meet the existing and projected needs of the customers of the City. This Plan supersedes the previous 2005 Water System Plan and has been prepared under the direction of the City of Ocean Shores City Council and Department of Public Works to meet the specific needs of the City while complying with Chapter 246-290 of the Washington Administrative Code (WAC) establishing planning requirements for public water systems. The Plan is also in accordance with the federal, state, and local rules and regulations governing the operation of public water systems as administered by the State of Washington Departments of Health and Ecology and, the codes and policies of Grays Harbor County. WATER SYSTEM DESCRIPTION The Ocean Shores water system is a Group A Public System owned and operated by the City. The system is self-sufficient in that it produces 100% of the potable water and fire protection service delivered to the 12- square-mile service area. Service is provided to approximately 5,800 connections including permanent single family residents, seasonal summer homes and cottages, hotels and motels, condominiums, commercial establishments, and recreational activities. Fluctuating water demands, high fire flows, and maintaining yields from groundwater wells have historically presented the biggest challenges in operating the water system. Water supply is from five active groundwater wells (Wells 4, 9, 11, 12, and 13) located on a wellfield at the City’s operations site near the center of the water system. The existing wells draw from a shallow aquifer and yield an annual average of approximately 813,000 gallons per day (gpd). Water is treated by a new (2011) state-of-the-art 2.0 million gallons per day (MGD) water treatment plant and stored after treatment in a 3.0 million gallon tank also located on the water operations site. The transmission and distribution system consists of three additional storage tanks, distribution and fire pumping facilities, emergency power generators, and a network of approximately 100 miles of water main. The distribution system consists of primary asbestos cement (AC) pipeline installed in the 1960s and ranges in size from 4 to 16 inches in diameter. The entire system is operated as a single pressure zone and operated at a single Hydraulic Grade Line. Page iii Executive Summary City of Ocean Shores Water System Plan Water storage tanks are designed to provide fire protection, standby, and equalizing storage to accommodate peak demands. Three of the storage tanks (North, Central, and South) each have a capacity of 1.0 million gallons (MG). The North and South storage tanks are concrete on-grade structures while the Central storage tank is a welded steel on-grade structure. The fourth storage tank is a 3.0 MG, welded steel structure located to the south of the main treatment plant buildings on the City’s water operations site near the center of the system. Chapter 1 of this Plan gives a system overview, describes existing water system facilities, and details the service area and related plans. PLANNING DATA AND DEMANDS Ocean Shores is a coastal resort community with the potential to triple in population to reach maximum development potential. Part of the water system planning process is projecting the timing of development so that water system upgrades can be appropriately planned for, constructed, and funded. Population projections and timing of development was coordinated with City planning efforts and the current Ocean Shores Comprehensive Plan. The City of Ocean Shores is located along the central Washington coast in Grays Harbor County. It consists of 5,575 acres of land supporting a variety of land uses typical to a coastal community with a fluctuating variety of seasonal tourism and recreational activities. The predominant land use for the City of Ocean Shores is single-family residential. Commercial land is concentrated in two distinct areas. The northern commercial area is the larger of the two and is adjacent to ocean beaches. It serves as the commercial gateway for the City and contains the majority of tourist-related City Housing Characteristics businesses and hotels. The southern commercial area located near the Renter marina is smaller in size. It remains Occupied (706) Summer/ less developed but has been Vacation Homes designated to serve the surrounding Vacant (1,583) (2,051) area. Owner Occupied According to the State Office of (2,001) For Sale (218) Other Financial Management (OFM), the City For Rent (109) had an estimated population of 5,600 (141) permanent residents in 2011. However, Ocean Shores is home to thousands more temporary residents during summer and holiday periods. The 2010 Census found a total of 4,758 housing units that have been constructed on approximately 34% of the residential lots platted within the City. A breakdown of housing units according to the 2010 Census is shown in the City Housing Characteristics chart above. Water system production has rebounded after reaching a low in 2011 of 233 million gallons and is projected to reach the 2009 figure of 300 million gallons by 2021. Production is projected to reach Page iv City of Ocean Shores Executive Summary Water System Plan nearly 400 million gallons by 2035. As noted in Chapter 2, key issues identified during the planning process are water production, authorized consumption, and sales tracking. Anomalies in billing data were attributable to issues with a billing system conversion which necessitated close scrutiny of water production and sales records. City staff continue to closely monitor records to determine actual water loss and determine the best measures for reducing the gap between water production and sales. It should be noted that while the analysis in Chapter 2 resulted in an estimated average distribution system leakage rate of 4.3% from 2011 to 2013, well below the 10% maximum established by DOH criteria, staff believe that this rate is likely to climb in the upcoming years. WATER USE EFFICIENCY AND REUSE As the City’s population increases, Ocean Shores recognizes that identification and implementation of programs to improve water use efficiency is a critical component of its water supply management. The City continues to promote water conservation as a means of preserving the longevity of existing water rights and has implemented a Water Use Efficiency (WUE) program based on a cost-effective analysis of measures that have the potential to reduce customer demands. The primary goal of the WUE program is to evaluate and implement measures that will assist in conserving water resources by eliminating non-essential water use both by customers and within the system during operations. The following goal has been developed as a part of this Water System Plan Update and represents the City’s goal for conservation for the next six-year period. “Ocean Shores will offer water conservation kits, leak detection kits, and promote water use efficiency through educational programs with a goal of saving 42,000 gallons per Equivalent Resident Unit per year by July 2019.” Historic conservation efforts, water use efficiency, water reuse, and the water shortage contingency plan are all discussed in Chapter 3 of this plan. REGULATORY REQUIREMENTS AND DESIGN CRITERIA The minimum design criteria used during evaluation of the water system for this Plan is summarized in the Water System Design Manual (DOH#331-123, December 2009 or latest edition) produced by the Washington State Department of Health (DOH). Criteria and performance standards for any new development or construction project in Ocean Shores are based on the current Washington State Department of Transportation’s Standard Specifications for Road, Bridge, and Municipal Construction, the Group A Public Water Systems Manual (WAC 246-290), and City design standards. Minimum design criteria outlined in Chapter 4 includes water supply requirements, storage volume, distribution system and transmission main capacity, pumping capacity, backup power systems, and water quality standards. These criteria are used to determine deficiencies in the existing water system Page v Executive Summary City of Ocean Shores Water System Plan and establish design requirements for any future improvements to the water system based on projected growth and increase in demands within the City's service area. In addition, the City is responsible for fulfilling the standards of water quality in accordance with WAC 246-290-310. Chapter 4 discusses all regulatory requirements, design criteria, and water quality standards for the City of Ocean Shores. SYSTEM ANALYSIS The system analysis performed for this Plan examined each major facility type– source, storage, pumping, and distribution. The primary focus of the system analysis is to determine the type and magnitude of improvements required to meet the projected needs of the anticipated population of the service area for both summer and winter. The number one strain on the system is fire flow, and it was examined in the analysis under low demand winter and high demand summer system operations.