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Dec
26

Rules, regulations, and policies

This page covers key policies for public and private water systems in King County.

Looking to build a home, buy a house with a water system, or drill a well? There are many rules and regulations that apply to creating and operating water systems. There are also rules that apply to how much water can be used for homes and businesses. Building projects that require drinking water also have rules and processes that must be followed. While professionals who submit and carry out development projects may be familiar with state and local land use and development codes, the following are a reference for anyone interested.

Washington state regulations

Washington state regulations apply to all counties in Washington. Counties can choose to adopt rules and regulations that are stricter than the state.

Public Water systems

  • Group A - WAC Chapter 246-290 sets regulations and is usually used by water professionals who build and operate Group A water systems.
  • Group B - WAC Chapter 246-291 sets regulations and is usually used by water professionals who build and operate Group B water systems. Many Group B water systems in King County are owned and operated by the community they serve, so people who are responsible for running Group B water systems should be familiar with this code.

Wells

WAC Chapter 173-160 sets regulations used mainly by well drillers but also sets constructions standards for wells that are important for developers.

Water rights

Title 90 RCW sets rules and regulations for water in Washington state that can be used and protected. The main thing to know is that water in Washington state is a public resource, meaning that everyone owns it, but there are many regulations in place to protect it from pollution and overuse.

King County regulations

King County has its own local rules that say what you can and can't do with water, and what considerations need to be made for water when developing a property. All King County rules are at least as strict as the state rules.

  • King County Board of Health, Title 12: Water (275 KB) – sets regulations for small public water systems in King County. The most important parts of this policy are the minimum setbacks from potential sources of contamination which apply to all water systems in King County. Homeowners, developers, and water professionals should be familiar with the minimum setback distances.
  • King County Board of Health, Title 13: On-Site Sewage (131 KB) – sets regulations for on-site sewage systems in King County. This policy is important for homeowners, water and wastewater professionals, developers, and health officers. It establishes what type of water system may be used for an on-site sewage system project, minimum lot size requirements, water quality and quantity standards for water systems, and the role of the King County health officers in siting and approving a water system.
  • King County Code, Title 13: Water and Sewer Systems – this sets rules for the long-term planning of water systems in King County, and is different from the King County Board of Health, Title 12: Water codes. The most important thing to know is that this policy sets Water Service Requirements (261 KB) that must be met for new development projects. If there is an available public water system for new development projects needing water, they should connect to it.
  • King County Board of Health, Title 21: Zoning – zoning regulations in King County. Zoning is important when planning a development and choosing where to put a water system. Based on how land is zoned and what environmentally sensitive areas might be on a property, some lots can be more difficult to build on than others. It is important for developers, water and wastewater professionals, real estate professionals, and interested property buyers to be aware of how easily a piece of land can be developed and what restrictions may apply.

King County watershed plans

Watershed Plans are required under the Streamflow Restoration Act RCW 90.94. You can think of a watershed as an area that channels water from rain and melting snow into a common body of water through a network of streams, rivers, and groundwater.

Water is a public resource that belongs to the residents of King County. Withdrawing groundwater requires special approval called a water right permit. Using water under a certain amount does not require a permit, and these water systems are called "permit exempt." Watershed plans try to improve streamflow to help fish by offsetting the impacts from new permit exempt wells. The main point from the King County Watershed Plans is that domestic permit exempt wells are limited to 950 gallons per day, per residence with an extra 1/2 acre of irrigation per permit exempt well. Public water systems, like Group B water systems, can use 950 gallons per day per residential service connection, up to 5,000 gallons per day with an extra 1/2 acre of irrigation for the whole system (not each residence).

Water shed plans apply to Water Resource Inventory Areas (WRIAs). The main WRIAs in King County are:

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