Chelan County Water Quality

Chelan County, Washington has a drinking-water quality grade of B with a score of 68.0/100, based on EPA SDWIS compliance data. The county has 2 health-based drinking water violations over the past 5 years. Watershed health, monitoring records, and live streamflow are reported separately on this page.

Chelan County has 2 health-based drinking water violations recorded by the EPA over the past 5 years. Health-based violations indicate instances where contaminant levels exceeded EPA Maximum Contaminant Levels (MCLs). Violations may have been resolved — check with your local water utility for current status.

EPA's Water Quality Portal records 19,596 measurements from 14 monitoring sites in Chelan County over the past five years. The most frequently measured characteristic groups are Organics, Pesticide, Not Assigned, Physical. Each measurement is a single sample analyzed for one characteristic (E. coli, pH, dissolved oxygen, etc.). High monitoring density means more scientific evidence behind any reported signal — it does not by itself indicate water quality.

Chelan County's SDWIS water quality score of 68.0/100 is higher than the Washington state average of 59.3. The average water quality grade across Washington is D, based on data from 39 counties with available SDWIS data.

Based on EPA SDWIS data, Chelan County has a water quality grade of B (68.0/100). This indicates good to excellent water quality with strong SDWIS compliance. The grade speaks to the public water system, not the watershed — for watershed-level concerns, see the Watershed Health zone. For the most up-to-date information, contact your local water utility or review your Consumer Confidence Report (CCR).

Chelan County has 2 health-based drinking water violations according to EPA records. With a water quality score of 68.0/100 and grade B, the county's drinking water has had some compliance issues but continues to be monitored. Note: drinking-water compliance speaks to the public water system, not necessarily to the watershed itself — check the Watershed Health zone for ATTAINS §303(d) data.

Chelan County ranks #13 out of 39 counties in Washington by SDWIS water quality score (1 = best). With a score of 68.0/100, it falls in the top third of counties statewide. The ranking reflects EPA SDWIS compliance only — not watershed impairment, monitoring density, or streamflow, which are tracked separately on this page.