Lower Cushman Dam, Hydroelectric dam in Mason County, United States

Lower Cushman Dam is a concrete arch-gravity dam on the North Fork of the Skokomish River in Mason County, Washington. It is 175 metres long, 2.4 metres wide at the crest and 12 metres at the base, and 53 metres high above the streambed. It impounds Lake Kokanee, a 3-kilometre reservoir, and feeds a powerhouse on Hood Canal via a 4-kilometre tunnel and three penstocks.

Construction of Cushman Dam No. 2 began in 1929, and power production started in December 1930. It forms the lower step of the Cushman Project, below Cushman Dam No. 1, using water from the North Fork Skokomish River. Its three 27-megawatt generators supply 233 thousand megawatt-hours annually to the Tacoma Power system.

The dam's water is diverted through a 4 km tunnel and three penstocks to a powerhouse on Hood Canal, so the North Fork Skokomish below the dam carries only a reduced flow. The Skokomish people have long fished and gathered along this river; the Cushman Project's diversion became central to their water-rights claims. Kokanee salmon in Lake Kokanee are named after the reservoir's own fish.

The dam is located in a forested valley and is best visited during drier weather when access roads and surrounding trails are easier to navigate. The site offers outdoor activities in the surrounding area, so it rewards a full visit to explore the river valley.

President Calvin Coolidge activated the power transmission lines of the Cushman dam system directly from the White House in an early remote control demonstration.