Water supply

We manage the state's water supply to meet the needs of people and the natural environment, in partnership with Washington communities. Water availability is increasingly limited in Washington due to the pressures of warming temperatures on snowpack and declining aquifers. We are committed to meeting current and future water needs to secure a healthy environment for generations to come.

Water availability

We study and regulate water resources by watershed. Find yours and see water availability.

Water rights

Streamflow restoration

We help protect rivers and streams while providing water for rural areas.


We provide well information and regulatory guidance for property owners and well drillers.


The Dam Safety Office (DSO) regulates nearly 1,100 dams in Washington.

Water supply projects in Eastern Washington

Our water supply and enhancement projects are providing water security in Eastern Washington.

Protecting stream flows

An instream flow is a water right for the stream and the resources that depend on it.

Water recovery solutions

As water for new uses becomes harder to find, we look for innovative solutions to meet future needs.