Snohomish River

Snohomish River
Snohomish River in Snohomish, Washington
Map of the Snohomish River and tributaries
Mouth of the Snohomish River in Washington
Snohomish River (the United States)
Location
CountryUnited States
StateWashington
CountySnohomish
Physical characteristics
SourceConfluence of the Skykomish River and the Snoqualmie River
  locationMonroe
  coordinates47°49′48″N 122°2′47″W / 47.83000°N 122.04639°W / 47.83000; -122.04639
MouthPuget Sound
  location
Port Gardner
  coordinates
48°1′16″N 122°12′30″W / 48.02111°N 122.20833°W / 48.02111; -122.20833
  elevation
0 m (0 ft)
Length20 mi (32 km)
Basin size1,856 sq mi (4,810 km2)
Discharge 
  locationNear Monroe
  average9,511 cu ft/s (269.3 m3/s)
  minimum763 cu ft/s (21.6 m3/s)
  maximum150,000 cu ft/s (4,200 m3/s)

The Snohomish River is a river in Snohomish County, Washington, formed by the confluence of the Skykomish and Snoqualmie rivers near Monroe. It flows northwest entering Port Gardner Bay, part of Puget Sound, between Everett and Marysville. The Pilchuck River is its main tributary and joins the river at Snohomish. The river system drains the west side of the Cascade Mountains from Snoqualmie Pass to north of Stevens Pass.

Measured at Monroe, the Snohomish River has an average annual flow of 9,500 cubic feet per second (270 m3/s). In comparison, the Columbia River, Washington's largest river, has an average flow of about 265,000 cubic feet per second (7,500 m3/s).