PASCO, Wash. – The Washington State Department of Agriculture (WSDA) is actively addressing high nitrate levels in the Pasco Basin through its Regional Pesticides in Groundwater Monitoring Program.
The program seeks to identify potential water quality issues early, ensuring public health and environmental safety.
In collaboration with the Benton Franklin Health District, the program provided free tabletop reverse osmosis units to residents affected by contaminated drinking water, the WSDA said in a release.
The initiative, funded by the Washington State Legislature in 2023, was created to monitor pesticides and nutrients in groundwater, particularly in agriculturally dense areas.
This effort is crucial as over 60% of Washingtonians rely on groundwater for drinking.
In the Pasco Basin, sampling began in fall 2024, covering 75 wells.
The WSDA said results showed that 10 locations had pesticide detections, with all levels well below 1% of the protective drinking water standard.
However, two-thirds of wells exceeded the nitrate standard for drinking water of 10 mg/L, the WSDA added.
The second round of sampling will be in fall 2025.
The program is underway in the Walla Walla Basin, sampling 40 wells. Further sampling in this region is planned for spring 2026.
