Lewis River (Washington)

The Lewis River is a tributary of the Columbia River, approximately convert|95|mi|km long, in southwestern Washington in the United States. It drains part of the Cascade Range north of the Columbia River. The drainage basin of the Lewis River is approximately convert|1068|sqmi|km2|0 large. The river's mean annual discharge is approximately convert|6124|cuft/s|m3/s. [http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/Vol%20II%20G--Lewis.pdf Lewis Subbasin Plan] , Northwest Power and Conservation Council]

Unlike nearby Lewis County and Fort Lewis the Lewis River was not named for Meriwether Lewis, but rather for A. Lee Lewis, an early settler who homesteaded near the mouth of the river. [cite book |last= Phillips |first= James W. |title= Washington State Place Names |year= 1971 |publisher= University of Washington Press |isbn= 0-295-95158-3]

Course

The Lewis River rises in the Cascades in northeastern Skamania County, east of Mount Adams, approximately 75 miles (120 km) northeast of Portland, Oregon. It flows generally southwest through Gifford Pinchot National Forest, across central Skamania county, passing south of Mount St. Helens. It forms the boundary between Cowlitz County, to the north, and Clark County, to the south. Towns along the river include Cougar, Ariel, and Woodland. In its lower 10 mi leg (16 km), it turns sharply south, then west, and enters the Columbia from the east, opposite St. Helens, Oregon, approximately 15 miles (24 km) north of Vancouver, Washington. The mouth of the Lewis River is at Columbia river mile 87.

Near the confluence with the Columbia River the Lewis River is joined by the East Fork Lewis River. The main Lewis River, sometimes called the North Fork Lewis River, [Gnis|1522046|Lewis River, USGS GNIS entry] forms the boundary between Clark and Cowlitz counties while the East Fork divides Clark County in half. The East Fork flows from headwaters located on the western flanks of Lookout Mountain in Skamaina County westward. Located along the East Forks are notable parks such as Moulton Falls, Lucia Falls, Lewisville, and Paradise Point. A variant name of the East Fork is the South Fork Lewis River. [Gnis|1519109|East Fork Lewis River, USGS GNIS entry]

River modifications

It is impounded for hydroelectricity in its middle course by Swift Dam, forming Swift Reservoir; Yale Dam, forming Yale Lake; and Merwin Dam, forming Lake Merwin.

References

External links

* [http://wa.water.usgs.gov/realtime/htmls/cowlitz.html USGS: Lewis River Basin]