Cooper Lake (120 acres): This high lake above Salmon-La-Sac is a consistent producer of brook trout and rainbows 7 to 10 inches. Small kokanee are also taken. Cooper Lake is accessible by road from the upper Cle Elum River, and a boat-launching facility is available. Gasoline motors are prohibited.
At approximately 2,789 feet (850 meters) above sea level and pierced with sundry old timber, this lake is fed and drained by the Cooper River, a tributary of the Cle Elum River, and hosts brook trout, rainbow, and kokanee, according to Foghorn Outdoors' 1996-97 Washington Fishing. What is not mentioned is that the lake has brown trout in it. Mike MacGregor