Lake Ewauna, Reservoir in Klamath Falls, Oregon, USA

Lake Ewauna is a reservoir in Klamath Falls, Oregon, fed by the Link River from Upper Klamath Lake and forming the headwaters of the Klamath River. Its level is held constant by releases from Keno Dam, 18 miles (29 km) south of the Link River's mouth. Dam and reservoir are part of the Klamath River Hydroelectric Project.

The lake was formed by damming the Link River as part of the region's water management system. During the 20th century, it played a key role in the lumber industry, with logs transported across its surface until the Modoc Lumber Company closed in the 1990s.

Lake Ewauna's length suits crew rowing, and the Ewauna Rowing Club has used the water for practice and competition since 1970. The lake is also the headwaters of the Klamath River, which begins here and flows from the Link River's inflow.

The lake's level is held steady all year by releases from Keno Dam, 18 mi (29 km) downstream of the Link River's mouth, so the water does not rise and fall with the seasons. In spring, logs that surface from the former log pond can be a hazard to boat traffic.

Every spring, old logs from the lumber industry's past surface on the lake. These remnants from decades of log handling require careful management to keep boats safe from potential hazards.