Snoqualmie

Watershed Hydrology

The Snoqualmie Watershed (HUC 17110010) covers approximately 684 square miles in western Washington state. It is characterized by a diverse hydrology due to the presence of several mountain ranges, including the Cascade Range. The watershed is known for its heavy snowfall in the winter, which contributes to a significant snowpack. Surface water in the watershed includes several major rivers, including the Snoqualmie River and Tolt River, as well as numerous smaller streams and tributaries. The watershed contains several reservoirs, including the Snoqualmie Falls Reservoir and the Tolt Reservoir, which provide water for hydroelectric power generation and municipal use. The climate in the Snoqualmie Watershed is characterized by relatively mild temperatures and high precipitation, with an average annual rainfall of over 80 inches. Interesting climatic trends include increased precipitation in recent years, as well as a decrease in the size and duration of the snowpack due to warmer temperatures.


Surface Flows

Snoqualmie Watershed

Snowpack Depths

Snoqualmie Watershed

Dams & Reservoirs

Snoqualmie Watershed

Groundwater Levels

Snoqualmie Watershed

Snoqualmie Rivers

Rivers of the Watershed