Lake Mills is a reservoir formed by the Glines Canyon Dam on the Elwha River located about 13 miles from the mouth of the river on the Olympic Peninsula. It is fully contained within Olympic National Park. The lake was created behind the Glines Canyon Dam. It was formed in 1927 with the completion of the dam and after the lowland forest that occupied the river bottom was clear-cut. With no fish passage facilities, the dam blocks passage of anadromous Pacific Salmon from the upper 50+ miles of the Elwha watershed located within Olympic National Park.