Ariel Dam, 1,343 feet in length and 313 deep, stretches across the western end of Lake Merwin, an artificial body of water created by the Northwest Electric Company as the first unit of a huge power-development program. Within the darn is a fish-preservation apparatus designed and operated by the State Department of Fisheries. A ten-ton steel tank containing water imprisons the fish as they come up the river. When the tank becomes filled with steel-head, salmon and other game fish, it is elevated by means of a derrick and its contents emptied into the lake above. In season, salmon are transported in specially constructed trucks to the fish hatchery three miles west. The crescent-shaped lake, which is eleven and one-half miles long and one-fourth of a mile wide, is in a basin where towering firs once stood. It offers excellent fishing, boating, and swimming. Surrounding it are 1,000 acres of evergreen forests, maintained for public recreation. Although the company does not permit the shooting of game in the recreational area, the adjoining territory abounds with duck, pheasant, bear, and deer, which may be hunted during the open season.