Arsenic in Washington Well Water

In Washington, arsenic levels average 3.57 ppb, with a maximum recorded level of 8.386 ppb. The EPA limit is 10 ppb. Currently 11.1% of tested wells exceed this limit, affecting approximately 53,280 wells.

Testing for arsenic in Washington typically costs around $52. If treatment is needed, water treatment systems for arsenic cost approximately $726.

The risk level for arsenic in Washington is rated as moderate. The state average of 3.57 ppb is 15.9% below the national average of 4.243 ppb.