Home e-Pay Doing Business News Employment Questions Conservation Water Quality Map


























Conservation of Water Resources

Summit Water’s Proposed Water Use Efficiency Measures and Goals

Water Use efficiency Rule


In 2003, the Washington State Legislature passed the Municipal Water Law (MWL). This law established that all municipal water suppliers must use water more efficiently in exchange for water right certainty and flexibility to help them meet future demand. The State Health Department has been directed to adopt an enforceable Water Use Efficiency (WUE) program intended to achieve a high level of stewardship among all municipal water suppliers.

Conservation Program Background


In 1993, Summit Water & Supply Co. (SWC) conducted a study to analyze the water demand characteristics with an eye toward determining opportunities for conservation. A conservation program was drafted and implemented using the information obtained from this study. In 1999, Summit Water revisited and updated its conservation program, which resulted in addressing and implementing additional conservation measures. Although Summit Water’s conservation program addresses both supply (source) and demand (customer) elements, from the standpoint of a conservation program, we believe that the demand side is ultimately the key to realizing significant savings. Through continued cooperation between Summit Water and its customers/members we will ensure an adequate supply of water now and well into the future.





Historic Conservation Measures (1993)

Summit Water originally implemented the following measures into its 1993 conservation program and continues to do so in its current program:

  • Contracted with independent leak detection company to perform water leakage audits, and repair/fix leaks as detected;
  • Purchased electronic leak detection equipment for use by Summit Water personnel in performing mainline and service line leak detection;
  • Initiated a comprehensive water meter change-out and service program, which replaced old meters with either new or newly calibrated meters. The meter change-out program was initially based on full replacement of meters within a 15 year cycle;
  • Make available toilet tank leak detection tablets to customers at Summit Water’s main office. Tablets are inserted into the toilet holding tank and if dyed water appears in the lower bowl this indicates a leaking flapper valve.
  • Installed meters on all water transfer connections to or from Summit Water’s system, with the most significant portion of this program being the installation of water lubrication meters on all vertical line-shaft turbine pumps; and
  • Continued customer conservation information/education through use of an annual news letter.



Current/Ongoing Conservation Measures

Along with those previously listed, are additional measures that have been implemented into Summit Water’s conservation program since 1999:


  • Provide customers/members information concerning water efficient fixtures and appliances, and encourage their use through education. Following is data provided by the AWWA, which indicates that installing water conserving fixtures can reduce indoor residential water use by as much as 30% verse no-conservation.

End Use Gal/Capita/Day Percent   Gal/Capita/Day
Toilets 9.3 52   10.0
Clothes Washers 11.8 30   5.0
Showers 11.1 16   2.1
Faucets 11.1 2   0.3
Leaks 4.7 50   4.7
Other Domestic 1.6 0   0
Bath 1.3 0   0
Dish Washers 1.0 0   0
Total 51.9 30   22.1


  • Support county initiatives to revise and/or develop building/plumbing code ordinances for water efficient construction;

  • Support the development and implementation of State conservation guidelines and local landscaping ordinances which promote water efficient use; Require a separate, interruptible meter for all playfields, parks, community, medium and large use irrigators;

  • Design and implement a “Supervisory Control and Data Acquisition” (SCADA) system, which can be used to program the operation of water sources and other facilities for maximum use efficiency;

  • Require an engineered “Landscape Plan” for all playfields, parks, community, medium and large use irrigators. 
    These plans determine the overall square footage of an area to be irrigated. This information is then used to establish irrigation “block rate intervals” based on the square footage of irrigated area. The first block allows for up to 1” of water per week based on the square footage calculation. The second block is for usage greater than 1” but not exceeding 1-1/4” based on the square footage calculation. While the third block is for usage greater than 1-1/4” based on the square footage calculation;

  • Notify customer of potential leaks based on abnormally high meter readings. The criteria for establishing an abnormally high meter reading is based on an increase of at least twice the average consumption for the same billing period in the prior two years. Upon the billing system identifying an account meeting the criteria, billing department personnel notifies the customer of our findings. The customer is advised on where to find information regarding leak detection services and is allowed a 50% credit (on leaks occurring between the meter and the house) towards the water usage portion of the bill, above their normal consumption for the same billing period if the leak is repaired in a timely manner;

  • Water meter connections which provide potable water are calculated and sized in part using the fixture count table in the “Uniform Plumbing Code”. Excluded from the fixtures count calculations are water connections which provide for the external use of water (i.e. irrigation, hose bibs, swimming pools);

  • Provide customers with historic water consumption on their monthly and bi-monthly bill. The data provided is shown by use of bar graph chart for the previous twelve (12) billings and provides water consumption in units by billing period;

  • Develop and implement an inverted block rate structure. This rate structure was designed to reward water conservation with lower bills for lower usage. The current water rate structure is an inverted block rate (three tiered), which means as a customer’s usage increases, their rates increase accordingly within the three block rates. Prior to the inverted block rate structure, many customers 
    were carrying the burden of costs associated with service to customers demanding higher water usage. The inverted block rate system places these costs more evenly on the basis of level of water units used;

  • Partnered with other members of the Water Cooperative of Pierce County in the group purchase of FCS Leak Detection Devices. These devices will be used and shared by those Coop members participating in the purchase of the leak detectors on a rotating schedule;

  • Continued education/information sharing with customers through use of Summit Water’s annual letter, web site, water bill information center and through our participation as a member of the Pierce County Regional Water Association.
  • Current Conservation Goals & Results

    The current conservation program was based on achieving the goals within a 5-year period. The goals set were as follows, reduce annual domestic demand per customer by 10 percent, reduce peak day demand per customer by 15 percent and achieve 10 percent or less of unaccounted for water.

    A. Reduce annual domestic demand per customer by 10% - From 1994 to 1998 Summit Water’s annual domestic demand per customer averaged 274 gallons per day (gpd). Since setting the new conservation goals in 1999, Summit Water has achieved an average annual domestic demand per customer of 243 gpd. This is a reduction of the annual domestic demand of approximately 11.3%, which exceeded the goal of 10 percent.

    B. Reduce peak day demand per customer by 15% - From 1994 to 1998 Summit Water’s peak day demand per customer averaged 703 gallons per day (gpd). Since setting the new conservation goals in 1999, Summit Water’s average peak day demand per customer is 625 gpd. This is a reduction of the peak day demand of approximately 11.1 percent. We continue to work towards achieving this goal.

    C. Achieve 10% or less of unaccounted for water - From 1994 to 1998 Summit Water had an unaccounted for water loss of 524,869,348 gallons or an average unaccounted for loss of 16.8 percent. Since setting this goal in 1999, Summit Water has had an unaccounted for water loss of 844,206,898 gallons or an average unaccounted for loss of 13.9 percent. Although we did not meet our goal of reducing unaccounted for water to 10% or less, we have on average over the last four years been able to reduce our unaccounted for water to 10.9%. We continue to work towards meeting the goal of 10% or less of unaccounted for water.

    Company Background

    Summit Water & Supply Co. is a mutual-like corporation organized under Chapter 24 RCW. 
    The company was originally established in 1923 and incorporated 1936. Summit Water provides domestic, commercial and light industrial service to approximately 6700 customers in north central Pierce County. 
    The service area lies between the corporate boundaries of Tacoma and Puyallup and south of the Puyallup River to 128th St. E. Summit Water serves in the low alluvial plain of the river, along the valley escarpment, and on the upland plateau. 
    Most of Summit’s Water service area is designated “Rural Separator”, but there are several small areas of higher density and non-residential land use. 
    The company’s service area is fixed under the Pierce County Coordinated Water System Plan and Summit currently has no plans to expand its service area. Summit Water has entered into inter-local service area agreements as required by the Pierce County Coordinated Water System Plan.


    Though nearly surrounded by urban areas, Summit Water’s service area is mostly designated as “Rural Separator” and excluded from Pierce County’s urban growth area. Much of the area is nearly rural in character with large lots and some agricultural uses. Higher density residential development is concentrated along the east side of Summit Water’s service area. Some multi-family residential is included in Summit Water’s mix (about 29%) and this has been the fastest growing class of customers. Non-residential development is found 
    in small centers, such as Summit Center near 112th St. & Canyon Rd. E., and along major arterial roads. The company also serves some trust lands of the Puyallup Nation, some of which are developed with residential and institutional uses.


    Summit Water operates a gravity supply system with approximately 3,850 gallons per minute (gpm) of source capacity and two 1500 gpm booster pumps capable of supplying water when the gravity supply system is unable to meet the demand. Total storage volume is approximately 3 million gallons. There are five pressure zones required to maintain suitable pressures on the system. The principal pressure zone is at a hydraulic grade elevation of 595’. Additional pressure zones are located at 522’, 390’, 205’ and 125’. The lower pressure zones rely in part on supply provided through pressure reducing valves.


    The water supply is entirely groundwater, from a total of nine wells at seven sites. All water sources are treated with chlorine for disinfection of the distribution system. Other water treatment includes the injection of caustic soda for pH adjustment to address corrosion control (copper levels).


    Summit Water has water rights for a total of 3,800 gallons per minute, and 2,130 acre-feet or 694,015,770 gallons per year. Additional sources of water include emergency inter-ties with Fruitland Mutual (1), Tacoma City Water (3) and one inter-tie with Parkland Light & Water, which is used for wheeling wholesale water to the company from the Lakewood Water District. The current Summit/Lakewood wholesale agreement allows for the purchase of up to 2-million gallons per day. Summit Water and Lakewood Water have entered into preliminary discussion for the purchasing of an additional 1-million gallons per day.


    In 1997, the Washington State Department of Ecology issued superseding certificates for all of Summit Water’s water rights that extended the place of use to include the areas served by other members of the Pierce County Water Cooperative. The purpose of this requested amendment to Summit’s water rights was to facilitate transfer of water between these systems to bring water that is available to areas where it is needed and could be put to beneficial use.



    System Demand Characteristics

    An evaluation of Summit Water’s annual water production and customer census (table 1) from 1994 through 2007 revealed that the average daily demand varied year to year from 230 to 300 gallons per day (gpd) for all users, with the overall average being about 260 gpd. Also noted from this evaluation was that Summit Water’s peak day demand varied year to year from 540 gpd to 780 gpd, with an overall average of 660 gpd.

    The most recent peak day was measured by Summit Water’s production instruments on July 11, 2007. On this day, 4,202, 000 gallons of water were pumped from all available sources. Net change in tank volume for the day was measured at approximately 64,000 gallons. A total of 4,260,000 gallons was consumed by 6667 customer units. This resulted in an average of 640 gallons being produced for each customer unit on the peak day.


    Proposed Growth

    The total number of legal recorded lots within Summit Water’s service area is estimated to be approximately 5,500. This estimate is made from map records obtained from the Pierce County Assessor’s office and information in Summit’s member files. Summit’s records show that there are currently 6667 users served by the water company. Commitments for service include 88 pending water availability certificates. These certificates are approved for an estimated 577 additional users. The high number of estimated users verses pending water certificates reflects the increasing multi-family and condominium development within the Summit area.

    Restrictions on further subdivision of land will determine whether and to what extent new lots are created. Most of Summit Water’s service area falls within the “Mid-County Community Plan” and is designated “Rural Separator”, which carries a 2.5 acre minimum restriction. Considering the restricted land uses and density, and the high proportion of lots of record already served, the company’s water system may be considered to be approaching the limits of growth.

    In order to estimate the future number of users, assumptions must be made for the number of users that arise from development of the remaining lots, and possible additions of users to lots already developed. The small areas of mixed and moderate density use within Summit’s service area may be developed by further subdivision of land.

    Lacking any specific data to predict the future rate of development, or the proportion of undevelopable land, it is estimated that together with the committed service to the current 6,667 users that an additional 1,100 users could be added by the year 2020.

    Projected Growth of Users


    1999 2000 2001 2002 2003 2004 2005 2006 2007 2010 2015 2020
    Residential 3879 4049 4175 4273 4263 4382 4393 4484 4497 4868 5111 5367
    Multi-family 1785 1785 1821 1829 1909 1909 1909 1909 1909 1923 1995 2095
    Small Commercial 113 117 118 118 120 122 124 125 128 130 136 143
    Med/Large Commercial 79 83 87 87 90 92 95 97 97 98 102 106
    Non-Potable/Irrigation 20 23 25 29 29 33 33 36 36 39 48 60


    5876 6057 6226 6336 6411 6538 6554 6651 6667 7058 7394 7772
    % Increase In Users   2.99% 2.71% 1.74% 1.17% 1.94% 0.24% 1.46% 0.24% 5.87% 4.75% 5.11%
Table 1
Water Production & Average Daily Demand 1994-2007
Production by Year 1994 1995 1996 1997 1998 1999 2000
Users by Year 4638 5145 5305 5364 5571 5876 6057
Adjusted Water Usage 493,880,326 509,292,682 519,836,052 519,338,966 556,226,130 545,091,109 533,661,431
Water Pumped 570,814,451 579,819,539 680,641,171 616,327,768 675,840,575 629,617,601 654,539,032
Difference 76,934,125 70,526,857 160,805,119 96,988,802 119,614,445 84,526,492 120,877,601
Unaccounted 13.5% 12.2% 23.6% 15.7% 17.7% 13.4% 18.5%
  2001 2002 2003 2004 2005 2006 2007
Users by Year 6226 6336 6411 6538 6554 6651 6667
Adjusted Water Usage 553,497,551 548,273,764 617,910,568 606,288,911 564,248,936 633,395,269 595,926,639
Water Pumped 596,755,441 669,266,641 747,109,950 657,295,774 614,340,238 716,921,815 685,823,802
Difference 43,257,890 120,992,877 129,199,382 51,006,863 50,091,302 83,526,546 89,897,163
Unaccounted 7.2% 18.1% 17.3% 7.8% 8.2% 11.7% 13.1%
Average Daily Demand per User
  1994 1995 1996 1997 1998 1999 2000
Avg Daily Demand / User 292 271 268 265 274 254 241
Peak Day Demand 3,597,048 3,406,156 3,462,443 3,808,790 3,991,464 3,541,110 3,837,970
Peak Day GPM 2,498 2,365 2,404 2,645 2,772 2,459 2,665
Avg Peak Day per User 776 662 653 710 716 603 634
  2001 2002 2003 2004 2005 2006 2007
Avg Daily Demand / User 244 237 264 254 236 261 245
Peak Day Demand 3,337,850 3,805,644 5,011,298 4,135,352 3,757,606 4,340,042 4,242,874
Peak Day GPM 2,318 2,643 3,480 2,872 2,609 3,014 2,946
Avg Peak Day per User 536 601 782 633 573 653 636



Natural Yard Care brochures from Tacoma-Pierce County Health Department

The following Adobe "PDF" files have been supplied for download if you wish.

These files are provided by Tacoma-Pierce County H. D.

Natural Lawn Care

Soils & Mulch

Integrated Pest Management

Planning & Planting

Watering Wisely

5 Steps to Natural Yard Care



Webmaster: dscott@summitwater.org

Home ]