Swift Reservoir, lake of the United States of America

Swift Reservoir is a 14 km long reservoir on the Lewis River in Skamania County, Washington, formed in 1958 when Swift Dam was built. It covers 18.7 km² and is fed by the Lewis River plus creeks such as Drift Creek and Range Creek, whose partly flooded valleys now form small bays. It is the uppermost and largest of three reservoirs on the river, with Yale Lake and Lake Merwin downstream.

The dam was completed in 1958 when the Swift Dam was built across the Lewis River to manage water flow. This construction was part of the region's water management strategy and permanently transformed the landscape from an open river valley into a recreation area.

The reservoir takes its name from Swift Creek, which enters right by the dam and rises on the south slope of Mount St. Helens. At the eastern end lie two recreation sites, Swift Forest Camp and Eagle Cliff Park, both with boat docks, reached by a Gifford Pinchot National Forest road along the north shore.

The site is easily accessible by Highway 503 with several parking areas and roads leading to campsites, boat ramps, and picnic areas. Bring water, food, and sun protection since there are no shops near the reservoir, and some parks operate only during warmer months.

Swift Reservoir is the uppermost and largest of three reservoirs on the Lewis River; downstream lie Yale Lake and Lake Merwin. Its name comes from Swift Creek, which enters right at Swift Dam and rises on the south slope of Mount St. Helens. The reservoir also holds Sensi Island, its only island.