Siltcoos Lake

Siltcoos Lake
View from Westlake Park
Siltcoos Lake
Siltcoos Lake
LocationNear Pacific Ocean coast in Douglas and Lane counties, Oregon
Coordinates43°52′54″N 124°06′45″W / 43.88167°N 124.11250°W / 43.88167; -124.11250
TypeNatural, permanent, eutrophic
Primary inflowsWoahink, Fiddle, Maple, and Lane creeks
Primary outflowsSiltcoos River
Catchment area68 square miles (180 km2)
Basin countriesUnited States
Surface area3,164 acres (1,280 ha)
Average depth11 feet (3.4 m)
Max. depth22 feet (6.7 m)
Water volume33,900 acre-feet (41,800,000 m3)
Residence time2 months
Shore length128 miles (45 km)
Surface elevation13 feet (4.0 m)
IslandsBooth, Reed (Webber), Jernigan (Goat), Boy Scout, Butterfly, Grass,
SettlementsDunes City, Westlake Siltcoos, Oregon
References
1 Shore length is not a well-defined measure.

Siltcoos Lake (silt’-koos), at 3,164 acres (1,280 ha), is the largest lake on the Oregon Coast of the United States. Fed by runoff from a basin of about 68 square miles (180 km2) in Douglas and Lane counties, it is about 7 miles (11 km) south of Florence and 0.5 miles (1 km) east of U.S. Route 101. Its name comes from a Lower Umpqua (Siuslaw) placename, a variant of which is Tsiltcoos.

The lake, with a mean elevation of 13 feet (4 m) above sea level, empties into the Siltcoos River, which meanders generally west for about 3 miles (4.8 km) to its mouth on the Pacific Ocean. A dam about a half-mile downriver regulates the lake's outflow.