Green River (Duwamish River tributary)

Green River
Looking upriver from suspension bridge in Isaac Evans Park, Auburn, Washington
Map of the Duwamish/Green River watershed with the Green River highlighted
Location of the mouth of the Duwamish River in Washington Show map of Washington (state) Green River (Duwamish River tributary) (the United States) Show map of the United States
Location
Country	United States
State	Washington
County	King
Cities	Auburn, Kent, Tukwila
Physical characteristics
Source	Cascade Range
• coordinates	47°8′N 121°18′W / 47.133°N 121.300°W / 47.133; -121.300[1]
• elevation	3,283 ft (1,001 m)[2]
Mouth	Duwamish River
• coordinates	47°28′N 122°15′W / 47.467°N 122.250°W / 47.467; -122.250[1]
• elevation	57 ft (17 m)[3]
Length	65 mi (105 km)[1]
Basin size	440 sq mi (1,100 km2)[4]
Discharge
• location	Auburn, Washington[4]
• average	1,316 cu ft/s (37.3 m3/s)[4]
• minimum	81 cu ft/s (2.3 m3/s)
• maximum	28,100 cu ft/s (800 m3/s)

The Green River is a 65-mile (105 km) long river in the state of Washington in the United States, arising on the western slopes of the Cascade Range south of Interstate 90.

The upper Green River valley forms the western approach to Stampede Pass, and was once home to many small railroad and logging towns such as Weston, Lester, Green River Hot Springs, Nagrom, Maywood, Humphreys, Eagle Gorge, Lemolo, and Kanaskat. Shortly before World War I, the City of Tacoma, Washington, filed for water rights on the Green River. Today, much of the upper valley has become a gated water supply watershed for Tacoma and access is heavily restricted, creating controversy among recreation enthusiasts.

Between 1880 and 1888, the Northern Pacific Railway explored and surveyed the Green River. The railway constructed the first direct rail link across Washington's Cascade Range with the opening of their Stampede Tunnel in 1888.