City of Selah Wellhead Protection Plan

The City of Selah is located in Yakima County in central Washington approximately 5 miles north of the City of Yakima. The City has historically owned and operated 7 wells:
  • Well Number 1 and Number 2 were drilled in 1919 and abandoned in 1952.
  • Well Number 3 and Number 4 constitute a well field, drilled in 1944 and 1947, respectively. Well Number 3 has a capacity of 600 gallons per minutes and Well Number 4 has a capacity of 800 gallons per minute.
  • Well Number 5 was drilled in 1951 and pumps 750 gallons per minute.
  • Well Number 6 was drilled in 1960 and pumps 1,500 gallons per minute.
  • Well Number 7 was drilled in 1994 and pumps 1,900 gallons per minute.
  • Well Number 8 was drilled in 2010 and is part of the well field with well's 3 and 4, and pumps 1,200 gallons per minute.
The City has total certified water rights in the amount of 4,760 acre-feet. 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 following table summarizes the acreage covered by each WHPA.

Analytical Model Area (Acres)

Source 6-Month 1-Year 5-Year 10-Year
Well Number 3, 4, and 8
15.2 26.2 118.3 263.0
Well Number 5
6.5 12.0 55.2 109.2
Well Number 6
6.5 12.0 55.3 109.6
Well Number 7
21.6 42.0 205.9 410.9
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 hazardous waste storage sites, underground storage tanks, leaking underground storage tanks, 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 all of the City's wells as having a moderate susceptibility to contamination, except for Well Number 7, which was ranked low in susceptibility.
  • Source Deficiencies: The City can currently meet the system maximum day demand with all sources in service as required by the DOH, but will require an additional 2,000 gpm to serve the growth projected for the next 20 years. However, if the City's largest well becomes contaminated, the City cannot meet its existing maximum day demand by approximately 450 gpm. The City plans to drill a well in the next 20 years to provide for additional source redundancy and 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 distance to the nearest potable water systems (City of Yakima and Yakima County Terrace Heights) is considerable, bottled water or tanker trucks in conjunction with water conservation/watering restrictions is the most appropriate short-term alternative water supply. Interties, new source development 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.