Minerva Terrace Water System Plan Part B Executive Summary

Transcription

1 Minerva Terrace Water System Plan Part B Executive Summary This water system plan was written using the Washington State Department of Health (DOH) Water System Planning Handbook, April Water System Plans (WSP) are required for the following system categories per WAC and WAC Water System Plans are required to be updated at least every ten years or when proposed projects are not included in the current WSP and a State Environmental Policy Act review is required. Mason County Public Utility District No. 1 (MCPUD1 or the District) owns and manages the Minerva Terrace Water System (#550709) which was acquired in The system is located approximately five miles south of Hoodsport along Highway 101 on the west shore of Hood Canal in Section 35, Township 22 North, Range 4 West, Willamette Meridian. MCPUD1 is obligated to serve the existing 34 connections and has a duty to serve the 49 developable lots within the service area boundary. Full build-out (FBO) for the system is 45 connections due to the combining of lots, the placement of the well on lot 15 and restrictions on development placed on 2 lots by the DOH. FBO is forecasted to occur within the 20-year planning period. INTRODUCTION The Minerva Terrace Water System was constructed in 1965 as part of the Minerva Terrace development which is located on the Skokomish Indian Reservation. The system does not have approval from DOH because it had never received design documents or a water system plan. The system is operating with a Blue status permit. This indicates that the system is adequate for existing uses but not for new service connections. DOH approval of the system will allow additional connections beyond the current 34. This report is requesting approval for 45 connections. The Minerva Terrace system has been treating the water for Coliform since 2010 with direct injection chlorination. The source of the E. Coli contamination was determined by the Dept. of Ecology to be coming from the well. Additionally, the water has had a higher than normal ph levels. The DOH conducted an investigation regarding complaints of skin irritation from Minerva Terrace residents. The cause of the elevated ph has not been determined. A list of follow-up actions to be completed by the District is contained in the letter Summary of Research and Findings located in Appendix G. Current distribution system loss (DSL) is 8%, which meets the State standard of 10% or less. This plan, which is the first developed for the system, provides basic information about the water system per WAC , WAC and WAC The following topics are covered in the full plan: A. Ownership and Management B. System Background C. Inventory of Existing Facilities D. Related Plans E. Existing Service Area Characteristics F. Future Service Area G. Service Area Agreements H. Service Area Policies I. Satellite Management Agencies J. Conditions of Service K. Complaints

2 SERVICE AREA The existing retail service area for Minerva Terrace is currently zoned in The Mason County Comprehensive Plan as Indian Residential. The lots in this development range from.14 acres to.56 acres. Service area, retail service area and place of use is shown below.

3 EXISTING SYSTEM DEMAND Historic source meter data from 2014 through 2017 was used for this plan. Average Daily Demand (ADD) is based on Equivalent Residential Units (ERU) which is the amount of water consumed by a typical full-time single-family residence for the system. ADD for the Minerva Terrace Water System is 163 gpd/eru based on source production. The current Peak Hourly Demand (PHD) is gpm and is below the instantaneous water rights of 75 GPM. The Distribution System Loss (DSL) for the system is 198,640 gallons per year based on the fouryear average of metered data. Based on three years of water use records ( ), distribution system leakage is 7.41%, which meets the required 10% or less state standard set by DOH. WATER RIGHTS, CURRENT USAGE AND PROJECTED NEEDS The water rights are sufficient to serve 45 connections at full build-out. The maximum allowable instantaneous flow rate is 75 gpm and the maximum annual volume is 18 ac-ft. The peak hourly demand for the 20-year planning period is expected to be gpm and the annual volume is expected to be 8.90 ac-ft without conservation. Water rights are discussed in Chapter 4 of the plan. System deficiencies and proposed solutions are discussed in Chapters 3 and 8. TREATMENT As discussed in the introduction, the Minerva Terrace system has been beset with multiple water quality issues. In 2009, water quality testing returned several positive results for total coliform. In October 2010, a positive test result for E. Coli prompted the Department of Health (DOH) to require permanent disinfection on the system. Design and operational information for the chlorination system is located in Appendix E. A summary of the water testing results is located in Appendix D WATER USE EFFICIENCY PROGRAM The District Board adopted water use efficiency goals and measures for the Minerva Terrace Water System on September 25 th Objectives of the District s conservation plan are to have distribution system leakage meet the 10% state standard within 6 years. The Minerva Terrace system is currently meeting this standard. WUE Goals for the Minerva Terrace Water System are: Production- 1. Maintain DSL levels to 10% or less. Consumption- 1. Reduce ADD by a minimum of 1% in 6 years. 2. Maintain ADD and summer peak demand. SOURCE PROTECTION MCPUD1 has developed Sanitary Control Areas and protective covenants for each water source which are on file with the Mason County Environmental Health Department. Protective well radii are a minimum 100 feet, unless a variance has been granted for a smaller radius. The protective covenants do not allow for any source contamination (livestock, hazardous material storage) within the 100-foot radius. The wellhead protection radius for the Minerva Terrace Water System was established using the Calculated Fixed Radius method as allowed by DOH. MCPUD1 developed the Wellhead Protection Program by

4 coordinating with local and state agencies as part of its water system management for its 73 water systems within Mason County. The Wellhead Protection Plan is also part of the Water System Plan Part A for MCPUD1. The District distributes wellhead protection information to system users to educate them. When warranted, additional information is provided to property owners and occupants adjacent to or may have a direct impact on the wellhead protection area and watershed control area. A Well Head Protection Notice is sent to property owners within the 10-year zones of contribution. An example of the letter can be found in Appendix D. OPERATIONS AND MAINTENANCE PLAN MCPUD1 provides day-to-day operations with water department staff performing all routine operational procedures for the water system overseen by the Director of Operations. Water staff also coordinates preventative maintenance of the water system. The Director of Operations - Oversees all engineering design, construction contract management and water supply operations for PUD No.1. The Director of Operations - Oversees all construction, coordinates all field maintenance and metering reading operations; oversees engineering designs and standards; review plans, water system compliance and construction management. The Director of Operations Relies on consulting civil engineers, that are licensed in the State of Washington to help in this endeavor. The plan also includes water quality control, emergency response, cross-connection control, implementation of the improvement program, budget formation, complaint response, public and press contact and billing. SYSTEM PROPOSED IMPROVEMENTS The well has exceeded its life expectancy of 50 years, having been constructed in The well had a sanding problem in 2000 and does not have a surface seal. The well has been determined to be the source of the E. coli contamination in A replacement well, constructed with a surface seal, will likely eliminate the need for treatment as well as resolve the high ph issue. The distribution system crosses an unnamed creek that runs between tract 1 and tract 2 of the development. These distribution mains are exposed at the surface in the creek-bed and are at risk of being damaged, which could contaminate the system. These mainlines should be replaced and located to a depth of six to eight feet. Installation of four isolation valves would reduce the loss of service to customers during repairs and main replacement work. Due to complaints from the residents regarding skin irritation, the DOH investigated and discovered higher than average ph levels (but not above action levels) and came up with a list of follow-up actions for the District to complete in order to reduce the elevated levels. A back-up generator located on site with an automatic transfer switch will ensure continuous service in the event of a power outage. The generator would be stored outside of the wellhouse and be ran with propane instead of diesel. All projects for the ten-year planning period can be completed by District staff other than installation of a new well.

5 IMPROVEMENT PROGRAM Based on the criteria established in chapter 8, the plan identified the needed improvements to be completed by MCPUD1 and are in the following list: The proposed improvement projects for the Minerva Terrace Water System during the next ten-year planning period are, in priority order: 1. Receive system approval from DOH for 45 connections. 2. Complete follow-up actions and recommendations from DOH investigation findings regarding ph 3. Drill and equip a replacement well for the water system. 4. Replace the distribution mains that cross the creek to a depth of six feet (currently exposed). 5. Install two isolation valves (see improvements map in Appendix F for locations) 6. Install backup generator at the source with automatic transfer switch IMPROVEMENT SCHEDULE PROJECT TITLE TYPE OF IMPROVEMENT DESCRIPTION COST ESTIMATE FINANCING SOURCE YEAR Well Replacement Drill and equip new well to replace existing well $150,000 Loan 2019 Isolation Valves Install two isolation valves on distribution system $3,000 Reserves 2019 Distribution Line Replacement Replace and bury the 2 mainlines crossing the creek $35,000 Loan Total $188,000 Backup Generator Install backup power generator, associated switching & electrical upgrades $73,000 Loan Total $73,000 WSP Part B Update Planning 10 Year Update of the WSP $33,000 Loan Total $33,000

6 FINANCIAL PROGRAM Historically, water systems tend to finance large capital projects where general funds or reserves are not adequate to provide the needed capital using long-term debt. The sources of these debt issuances are Public Works Trust Fund (PWTF), Federal Housing Administration (FHA), or private financing (banks). The size of the individual systems makes it prohibitive to enter the bond market. These types of financing sources are used only for Capital Projects for the Minerva Terrace Water System. Meter rates nearly double if bank loans are used due to their higher costs and are avoided where possible. Revenue for the past three years has been steady, and the system currently has no debt payments. The system was acquired by MCPUD1 in The average annual surplus is approximately $3,200. The Minerva Terrace Water System financial statement for 2012 through 2017 is shown in Chapter 9.