The Cascade Canal is a canal located in Klamath and Jackson counties, in the U.S. State of Oregon. It delivers water from Fourmile Lake in the Klamath River watershed over the Cascade Divide to Fish Lake in the Rogue River watershed.It diverts approximately 5,462 acre-feet (6,737,000 m3) annually into Fish Lake.About 33 percent of the water diverted from Fourmile Lake is lost or spilled on the way to Fish Lake.