Many people in the Lower Yakima Valley depend on ground water as a drinking water source. Past study results show that 12% of the valley’s wells that have been tested do not meet drinking water quality standards for a chemical called nitrate. About 20% have elevated levels of nitrates, and many are above the background level for the area. Increased awareness of groundwater contamination in private drinking water wells prompted the Washington State Department of Ecology (Ecology) to work with the U.S. Environmental Protection Agency (EPA), Washington State Department of Agriculture (WSDA), Washington Department of Health (WDOH), and Yakima County to address the many challenges associated with regional groundwater contamination.
Nitrate reduces the ability of red blood cells to carry oxygen. Infants under six months of age, pregnant women, individuals whose bodies are unable to break down methemoglobin to hemoglobin efficiently, and those with low levels of stomach acid are at risk if their drinking water supply exceeds the nitrate drinking water standard of 10 mg/l nitrate-nitrogen. Infants who drink water with high levels of nitrate (or eat foods made with nitrate-contaminated water) may develop a serious health condition, called methemoglobinemia or “blue baby syndrome”, due to the lack of oxygen.
Ecology, EPA, WSDA, WDOH, and Yakima County completed a report titled “Lower Yakima Valley Groundwater Quality - Preliminary Assessment and Recommendations Document”. The report describes the various problems identified by community members, agriculture, health, and environmental professionals associated with the groundwater pollution and:
Quality of Ground Water in Private Wells in the Lower Yakima Valley,
2001-02 (Ecology publication)
Lower Yakima Valley Groundwater Quality: Preliminary Assessment
Request for Identification:
Lower Yakima Valley Groundwater Management Area (Pacific Groundwater
Administrative Order Activating the Lower Yakima Valley Groundwater Management Area
Ecology’s Groundwater Quality
WDOH Drinking Water Program
Well Water Quality and Infant Health Study
Important Information for Private Well Owners (WDOH Publication)
EPA Office of Drinking Water
Yakima County Health Department Drinking Water Page
EPA and Yakima Valley dairies consent decree (March 19, 2013)
EPA’s Lower Yakima Valley groundwater website
Lower Yakima Valley Groundwater Quality
Charlie McKinney Water Quality Program - Central Regional Office Washington State Department of Ecology Phone: (509) 457-7107 E-mail: Charlie.McKinney@ecy.wa.gov
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