Groundwater permit exemption

The groundwater permit exemption allows four small uses of groundwater without a water right permit:

  • Domestic uses of less than 5,000 gallons per day
  • Industrial uses of less than 5,000 gallons per day
  • Irrigation of a lawn or non-commercial garden, a half-acre or less in size
  • Stock water

About permit-exempt wells

In 1945, the Legislature established the Groundwater Code, Chapter 90.44 RCW. In the code, they identified certain "small withdrawals" of groundwater as exempt from the permitting process. These uses are commonly referred to as "permit exempt."

Permit-exempt groundwater wells often provide water where a community supply is not available, serving single homes, small developments, irrigation of small lawns and gardens, industry, and stock watering.

Although permit-exempt wells don’t require a water right permit — to the extent that the well is regularly used — a right is established that is equal to a permitted right. For example, an existing permit-exempt well may not be impaired by a junior water user.

Permit-exempt water users do have the option of applying for a water right permit from us even if their uses fall within the purposes and quantities listed above. For a permit to be granted, the application must pass the four-part test, the same as any other water right application.

Restrictions to permit exemptions

Water use of any sort is subject to the prior appropriation doctrine, also referred to as "first in time, first in right." This means that a senior right cannot be impaired by a junior right. Seniority is established by priority date — the original date a water right application was filed, or the date that water was first put to beneficial use in the case of claims and exempt groundwater withdrawals.

  • One groundwater exemption is allowed for any one project, regardless of size.
  • All wells for a given project apply toward the limits of the exemption.

If you intend to develop land and supply the industrial or domestic development with water from several wells, all the wells of the development together may only pump 5,000 gallons per day (gpd) under the exemption. For example, a project that includes multiple homes, such as a small subdivision, can legally use the exemption as long as the homes collectively will use no more than 5,000 gpd for their domestic water needs. If the cumulative total of groundwater used for an industrial or domestic project exceeds 5,000 gallons a day, a water right permit is required.

Exempt uses are still subject to water law

Although exempt groundwater withdrawals don’t require a water right permit, they are always subject to state water law. In some instances, we have had to regulate exempt groundwater withdrawals when they interfere with prior or senior water rights, including instream flow rules.

A 2018 law impacts new residential permit-exempt wells in some rural parts of the state. The law lays out interim standards until local communities develop plans to invest in projects that help fish and streamflows.

More information