Clean & safe water for communities

Well monitoring program to begin in the Lower Yakima Valley to track nitrates

Elevated concentrations of nitrate have been found in drinking water in some areas of the Lower Yakima Valley. Because of potential health effects associated with nitrates, we’ve been working locally to find solutions.

To better understand the situation, we need more information about the condition of the aquifers that provide drinking water for as many as 56,000 residents in the area. To do that, we're offering free sampling to those with private drinking water wells in the Lower Yakima Valley Groundwater Management Area (see map), during a long-term monitoring program.

You can help with this drinking water study

Beginning on May 17, 2021, we will be in the field reaching out to residents to encourage them to participate in the study. We hope to have 170 wells in our monitoring network by the time we start sampling in July.

“This will help you protect yourself and your family from potentially harmful chemicals while helping our scientists research ways to prevent contamination,” said Melanie Redding, a hydrogeologist with Ecology’s Environmental Assessment Program.

Throughout the study we will send participants test results and explain what they mean. If testing shows there are potentially harmful chemicals in well water, we may advise people to rely on other sources of drinking water. Information on the study can be found on our website.

To participate, please contact Melanie Redding, who will work directly with homeowners and residents to arrange for testing. Call 360-407-6524 or email to sign up.

Monitoring a top priority

As we wrote in January 2020, before the pandemic closures, we sought and received $378,000 in funding from the Legislature as part of Gov. Jay Inslee’s 2020 supplemental budget to expand monitoring for nitrates in private drinking water wells in the Lower Yakima Valley.

Over the years, we've lent support to provide research, data, and technical expertise to the community-based Lower Yakima Valley Groundwater Management Area (GWMA) committee's work to tackle and reduce sources of nitrates in drinking water.

The GWMA effort consisted of Yakima County, Yakima Health District, South Yakima Conservation District, Washington State Department of Ecology, other state and federal agencies, farmers, livestock producers, environmentalists, and concerned residents.

The goal of the Lower Yakima Valley Groundwater Management Area Program is to reduce nitrate concentrations to meet drinking water standards and help ensure drinking water is clean and safe. This groundwater study is one of the priorities identified in the plan that was certified in 2019.