City of Yakima Wellhead Protection Plan

The City is situated in the Upper Yakima Valley of central Washington, on the relatively flat plain just south of the Yakima Ridge. Yakima is bordered by the City of Union Gap to the south, the Yakima River to the east, and the Naches River, a tributary to the Yakima River, on the north.

Outlying areas include Moxee to the east, Cowiche, Tieton and Naches to the west, and Selah to the north past the gap in the Yakima Ridge.

The City has currently owns and operates 4 wells:
  • Kiwanis Park Well was drilled in 1961 and pumps 2,350 gallons per minute.
  • Kissel Well was drilled in 1991 and pumps 3,000 gallons per minute.
  • Airport Well was drilled in 1962 and pumps 2,700 gallons per minute.
  • Gardner Well was brought online in 2012 and pumps 3,000 gallons per minute.
All of the City's wells are emergency backups to the City's Water Resources Division treatment plant, which treats water from the Naches River. The City has total certified water rights in the amount of 10,080 acre-feet for its emergency wells. The City’s sources have historically provided high quality water.

Wellhead Protection Area Delineations
The City's wellhead protection areas (WHPA) were delineated using an analytical model. The table below summarizes the acreage covered by each WHPA.

Analytical Model Area (Acres)

Source 6-Month 1-Year 5-Year 10-Year
Airport Well
6.0 10.6 47.7 93.7
Kiwanis Well
14.6 28.5 139.0 283.0
Kissel Well
6.5 11.6 52.3
Gardner Well
45.0 85.0 369.0 715.0

Inventory of Potential Contaminant Sources

After delineating the WHPAs associated with the City’s wells, an inventory of existing and potential sources of groundwater contamination (PDF) was compiled and mapped. High risk potential contamination sources located near the City's wells include underground storage tanks, leaking underground storage tanks, confirmed or suspected contamination sites, hazardous waste handlers, high risk businesses, and agricultural land which may be susceptible to pesticide use.

Contingency Plan

The City's contingency plan consists of the following components:
  • Susceptibility Assessments: The Washington State Department of Health (DOH) has ranked the Airport Well and Kiwanis Well having a low susceptibility to contamination and the Kissel Well as having a moderate risk.
  • Source Deficiencies: The City cannot currently meet the existing system maximum day demand with its wells by approximately 4,300 gallons per minute if the Naches River Water Treatment Plant is removed from service. In the next 20 years, this shortfall is expected to increase to approximately 5,400 gallons per minute. The City plans to provide sufficient backup source capacity in the next 20 years to provide sufficient redundant source capacity.
  • Emergency Response: The City has developed an emergency response plan that includes an emergency call-up list and response procedures for spills, fires, and water supply contamination.
  • Short-Term and Long-Term Water Supplies: Because the City of Yakima has two existing interties with the Nob Hill Water Association, these represent the most appropriate short-term alternative water supply in an emergency situation. New source development, further use of the intertie, and groundwater remediation are the most appropriate long-term alternatives.

Local Management Plan

Local management efforts adopted by the City include:
  • Posting of street signs at wellhead protection area boundaries
  • An annual school seminar program to promote wellhead protection and water education
  • Distribution of literature
  • Notification of residences and businesses within the City's wellhead protection areas
View the Regional Management Plan page for more information.