Water Quality

Our mission is to keep Washington waters clean. Use this site to find out if a lake, stream, or marine beach near you is healthy or polluted. Learn about water cleanup plans and how we’re addressing stormwater runoff, promoting good wastewater management, and protecting wetlands that are important for habitat and flood control. Explore the connections between underground aquifers and surface water. Read why our scientists are concerned about changing trends in Puget Sound’s water quality.

Water improvement

We protect Washington waters from pollution so they meet state water quality standards.

Water quality standards

We restore and protect rivers, lakes, groundwater, and marine waters using water quality standards.

Water quality permits

Permits protect water quality/public health & regulate treatment/discharge of wastewater/stormwater.

Water quality grants and loans

Stormwater & runoff

We identify and reduce sources of polluted runoff as part of our Clean Water Act responsibilities.


We limit the pollution that wastewater treatment plants and industries discharge into state waters.

Reclaimed water

Reclaimed water is treated wastewater, safely used for irrigation, toilet flushing, or landscaping.


We work to protect groundwater from pollution so that it's drinkable and meets state standards.


We work to protect Washington's marine resources.


We work to restore and protect rivers and lakes from pollution.