Water Use Efficiency Program 2019 Update

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1 Water Use Efficiency Program 2019 Update INTRODUCTION The City of Enumclaw recognizes that water is a valuable and essential natural resource that needs to be used wisely. This program provides an approach to increase water use efficiency (WUE) within the City s water service area and has been prepared to be fully compliant with Washington State Department of Health WUE requirements. RULE BACKGROUND AND REQUIREMENTS In 2003, the Washington State Legislature passed Engrossed Second Substitute House Bill 1338, better known as the Municipal Water Law, to address the increasing demand on our state s water resources. The law established that all municipal water suppliers (MWS) must use water more efficiently in exchange for water right certainty and flexibility to help them meet future demand. The Legislature directed the Department of Health to adopt an enforceable WUE program, which became effective on January 22, To assist MWS with complying with the WUE rule, the Department of Health (DOH) has produced DOH Publication , the Water Use Efficiency Guidebook. The WUE requirements emphasize the importance of measuring water use and evaluating the effectiveness of a WUE program. There are three fundamental elements: Planning Requirements. As part of a water system plan, MWS are required to: Collect data. Forecast demand. Evaluate WUE measures. Distribution Leakage Standard. MWS are required to meet a distribution system leakage (DSL) standard to minimize water loss from their distribution system. WUE requirements establish a 10 percent or less DSL standard based on a 3-year rolling average. If the DSL exceeds 10 percent the MWS must develop and implement a water loss control action plan in order to be in compliance. Goal Setting and WUE Reporting. Every 6 years at a minimum and at each water system plan update, MWS are required to set WUE goals through a public process. MWS must report annually on their performance to the DOH and make the information available to the public. Goals must be measurable, address water supply and demand forecasting, and include an implementation schedule for each goal. The requirement for reporting to the public may be fulfilled by including information in the annual Consumer Confidence Report. COMPREHENSIVE WATER SYSTEM PLAN 1 (2/11/19-15:15)

2 WATER SUPPLY CHARACTERISTICS The City owns and operates 5 groundwater supply facilities at four sites to the east of the City: Boise Springs, Watercress Springs, Golf Course Well, and PC Johnson Wellfield. The City also has an emergency intertie connected to the Tacoma Water pipeline that carries surface water from Tacoma s Green River source through the City. Water produced at the spring sites and wells is chlorinated, while water supplied from the spring sites receives additional treatment for corrosion control. Water from Tacoma is chlorinated and fluoridated. Water storage is provided by five reservoirs that have a total maximum capacity of 5.74 million gallons (MG). In addition, the City s water system has nine pressure zones with one pressure reducing station, seven booster pump stations, and more than 145 miles of water main. Chapter 2 of the City Comprehensive Water system Plan (CWSP) includes more detailed information on the City system. Chapter 6 of the CWSP includes detailed information on the City s water rights. While the City has sufficient supply from its existing sources to meet the demand requirements of the system for the planning horizon of year 2033, the future system capacity analysis in Chapter 7 of the CWSP concluded that the most limiting factor of future system capacity is the supply for the maximum day demand (MDD) scenario. If the MDD were reduced the City would have more capacity to meet future supply needs. HISTORICAL WATER USE EFFICIENCY PROGRAM The planning element of a WUE program requires the collection of water use data, forecasting demand, and evaluating WUE measures. The City s system is fully metered at all production and intertie sources and at customer connections. Installing meters is one of the most significant WUE requirements because meters provide the information necessary to calculate accurate distribution system leakage and evaluate the effectiveness of a WUE program. The water utility is in the 2nd year of a 4-year program to convert from a manual to an automatic meter reading system. Manual meters are read monthly and source meters every day. Automatic read meter usage data can be extracted at any time. Data from the metering program and system-wide demand forecasts are contained in Chapter 4 of the CWSP. As noted in Table 4-1 in Chapter 4, water consumption dropped from 132 to 111 average gallons per day per capita from 2004 to Factors believed to contribute to the decline include customer and supply side conservation efforts, adverse economic conditions, adoption of a residential increasing rate block structure, and significant increases in sewer volumetric rates to finance expansion of the City s wastewater treatment plant. Since 2011 the annual average water usage per single family residential connection seems to have become fairly consistent, ranging from 186 to 199 gallons per day depending upon the dryness of the year, indicating that the effect of the factors above seems to have stabilized. From 2007 to 2011, the use per single family residential connection ranged from 183 to 226 gallons per day. The WUE goal adopted by the City in the 2007 CWSP targeted achieving an average water use reduction of 5 percent by the year 2012 with 2004 as the base year. As of the end of 2011 average residential water use dropped by 12 percent from 2004 based on a 3-year average, representing a savings of nearly 150,000 gallons a day. (2/11/19-15:15) 2 COMPREHENSIVE WATER SYSTEM PLAN

3 Water Use Efficiency Program WUE goals adopted in 2013 included: Goal #1. Maintain a three year running annual average of less than 200 gallons per connection per day (gpcd) for single family residential usage. Goal #2. Reduce the yearly ratio of maximum to average day demand so that by 2017 and thereafter it does not exceed 1.8. Goal #1 has been met with the three year annual average ranging between 185 and 191 gallons per day since An estimated annual average reduction in consumption for single family residential customers of 15 million gallons or an average of 41,000 gallons per day was achieved for the period of compared to the prior period of Goal #2 was not achieved except in 2013 when the ratio was WUE measures evaluated and/or implemented by the City include the following: Public Education Theme Shows and Fairs Portable displays and other educational materials are exhibited at local fairs and theme shows. This measure has been accomplished by the Saving Water Partnership, King County, and larger MWS. Because resources to accomplish this conservation measure are allocated at the regional level, rather than directly from Enumclaw, this measure is highly costeffective for the City. Program Promotion Conservation related informational and/or promotional materials are included in each annual consumer confidence report. The City has also included information with utility bills and on the City s website. Other more costly measures such as newspaper articles, radio advertisements, or presentations at local schools are not implemented due to limited resources and the fact that other measures, such as water and sewer rates, have a much larger effect. Bill Showing Consumption History Water bills received by the City s customers compare current water use with consumption history of the same period in the previous year. System Measures Source and Customer Meters Every source has a water meter that is read and recorded each day. All customer services are metered and are read at least monthly. Leak Detection and Repairs The City has conducted leak surveys when its Distribution System Leakage was near or exceeded 10 percent and when contracting leak detection services for pinpointing a known leak and more time was available in the minimum charge allotted for a service call. Leaks are repaired as soon as practical. Incentives/Other Measures Conservation Pricing - The City adopted an increasing rate block structure for residential customers beginning in Water used above specified levels is charged at a higher rate. COMPREHENSIVE WATER SYSTEM PLAN 3 (2/11/19-15:15)

4 Although separate from the water utility, the City s sewer rates include a volumetric charge that in 2019 is 2.9 times larger than the middle rate block for inside City residential customers and may be the largest contributing factor to reduced customer water consumption. Seasonal Demand Management - The City has requested customers to voluntarily restrict outdoor water usage to odd/even days in accordance with their street address to reduce summertime peak water demands. With sufficient participation, this measure may be very cost effective in reducing maximum day demand, currently the most limiting factor in the water system s capacity to accommodate additional growth. Unfortunately, experience from has shown that request for voluntary restriction have apparently gone unheeded. Recycling/Reuse The City considered potential water reclamation opportunities in the 2007 and 2013 CWSPs. All of the potential opportunities identified would require Class A effluent that would require a filtration system at the City s Wastewater Treatment Plant to produce. This could cost several hundred thousand dollars, depending on the volume of Class A quality reclaimed water to be produced, just for the additional treatment. However, use of reclaimed water by many of the City s largest potential non-potable water consumers would be unlikely because they are scattered throughout the water service area and their distance from the wastewater treatment plant would make such use cost prohibitive. Customers in closer proximity to the wastewater plant are the most likely candidates for use of reclaimed water, but the costs to install the infrastructure to deliver the treated effluent could easily be much higher than that estimated for installing the treatment. In summary, the cost of providing reclaimed water would still easily exceed the cost savings that would be realized from the reduced use of potable water. In addition, current regulation and opposition from tribes and other environmental groups would likely prevent implementation of a reuse program that would remove any of the flow that enters the White River from the City s wastewater treatment plant. DISTRIBUTION SYSTEM LEAKAGE Authorized consumption is defined as the volume of water authorized for use by the water system. All unauthorized uses and any water that cannot be tracked is considered DSL. DSL is defined as the water lost from the distribution system and includes both apparent losses and real losses. Apparent losses include things such as theft, meter inaccuracies, and data collection errors. Real losses are the physical losses from the distribution system and include such things as reservoir overflows, leaky valves, and water main breaks. Neither apparent nor real losses are authorized uses of water, therefore they are considered leakage even if they are not actual leaks. Known or credibly estimated losses can be excluded from the leakage calculations and may include uses such as firefighting and flushing. The City s calculated DSL history from 2004 to 2012 is shown in Table 4-7 in Chapter 4 of the 2013 CWSP. The City s DSL of 9.5% in 2011 is significantly lower than the 49 percent DSL experienced in The decrease is primarily due to the repair of a leaking reservoir and an extensive water main replacement program in 1997 through DSL from 2013 to 2018 is shown below: (2/11/19-15:15) 4 COMPREHENSIVE WATER SYSTEM PLAN

5 Water Use Efficiency Program Distribution Year System Leakage (%) % % % % % % % PROPOSED WATER USE EFFICIENCY PROGRAM The WUE rule requires that the City evaluate WUE measures for their cost-effectiveness in supporting the adopted WUE goals. Measures must be evaluated for cost-effectiveness from the following categories: indoor residential, outdoor, and industrial/commercial/institutional. Certain measures can be used for more than one category. Measures Conservation Rate Structure. The City s increasing block structure has been in place since 2007 and has played a role in reducing consumption. The actual water reduction benefit attributable to the water rate structure is impossible to quantify because several significant sewer rate increases were also put in place during the same period. Regardless, it is believed that this measure is cost effective at reducing water use. Notifying Customers Regarding Leaks on Their Service. The City data collector for manual read meters alerts staff to unusually high water consumption at a customer service. The automated read system alerts staff to high consumption at a service based on a staff selected threshold. The customer is notified of the potential leak by posting a notice on the customer s door and/or by phone or . This measure has been highly effective. Educating Customers. Educating customers more than once per year about the importance of using water efficiently counts as a WUE measure. This will be accomplished through an article in the annual consumer confidence report, through an informational note at least once per year on each customer s utility bill, and conservation tips on the City s website. The cost is nominal but will serve as a reminder to customers of the need to use water efficiently. Water Bill Showing Consumption History. The City will continue to include on water bills current water use compared to consumption of the same period in the previous year. This measure does not require any additional resources from the City that is not already in place. Therefore this is a cost-effective measure. Water Demand Forecast Table 1 shows future water demand projections with and without WUE program goals and the resulting savings in maximum day demand if the goals are realized. At buildout of the City s COMPREHENSIVE WATER SYSTEM PLAN 5 (2/11/19-15:15)

6 current urban growth area the savings are approaching the current purchased maximum day capacity of the Tacoma intertie source of 424 gpm. This will serve to further delay the need for converting the intertie into a seasonal source and defer the need for manganese removal treatment at the PC Johnson Wellfield. Table 1 Future Water Demand Projections ADD MDD MDD w/ WUE Savings Year Population ERUs (gpm) (gpm) (gpm) (gpm) ,713 7,573 1,173 2,463 2, ,159 7,788 1,206 2,533 2, ,621 8,011 1,241 2,605 2, ,101 8,242 1,276 2,680 2, ,598 8,481 1,313 2,758 2, ,113 8,730 1,352 2,839 2, ,647 8,987 1,392 2,923 2, ,989 10,116 1,567 3,290 2, ,846 11,011 1,705 3,581 3, Buildout 23,842 11,491 1,779 3,737 3, Goal Setting Goals that support the Water Use Efficiency Program are to be established by the elected governing board, the City Council, through a public process, including a public hearing with notice of the hearing placed in the local newspaper, on the City website, and on customer utility bills. Goals must be evaluated at least every 6-years and at every water system plan update. The next water system plan update must be adopted in In setting new goals until the next water system plan update in 2023, it is recommended that goals continue to focus on achieving a reduction in the maximum day demand, the most limiting factor of the system s capacity to accommodate future growth. Limiting the maximum day demand will also work to defer the need for expensive manganese removal treatment at the PC Johnson Wellfield or the need to convert the Tacoma intertie from an emergency to a seasonal source. The cost for treatment of the wellfield is estimated to exceed $2.5 million. The cost to convert the intertie to a seasonal source would be minimal since the infrastructure is already in place. However, City policy continues to be to avoid using the intertie due to the substantial difference in water quality and the fact that it costs less to produce water from City sources. Also, once the intertie is converted to a seasonal source the City will have to comply with the more rigorous reporting and frequent monitoring required of a surface water source. The following goals are proposed for the 2019 to 2023 time period. (2/11/19-15:15) 6 COMPREHENSIVE WATER SYSTEM PLAN

7 Water Use Efficiency Program Goal #1. Reduce DSL to 5% by 2023 through additional steel water main replacements, by conducting annual leak surveys and fixing any identified leak as soon as practicable, and completing the conversion to a new automated meter read system to more accurately measure consumptive use. Goal #2. Reduce the annual volume of single family residential customer leakage billing adjustments by 10% by 2023 utilizing the new automated meter reading system to identify and notify customers of leaks more quickly than possible through the manual monthly read system. PROGRAM MONITORING AND REPORTING The City will continue to monitor overall water use and the amount of distribution system leakage on an annual basis. The City will monitor the success or failure of its water conservation program by analyzing this data and determining the long-term trend in water usage. The City will also evaluate the cost-effectiveness of water conservation methods, both implemented and not implemented, to determine if existing methods should be continued, or if new methods should be instituted. If the results of the program monitoring show that the water savings goals are not being met, more rigorous program implementation or additional program items will be considered. Annual performance reports will be submitted to DOH as required and a copy of the report posted on the City s website. City water customers will also be provided updates on WUE program results in the City s annual Consumer Confidence Report. COMPREHENSIVE WATER SYSTEM PLAN 7 (2/11/19-15:15)