Sullivan Lake, a high-traffic camping and boating spot in northeastern Washington's Selkirk Mountains, owes part of its popularity to two small dams. Built nearly a century ago, the dams once powered the Inland Portland Cement Co.'s operations in nearby Metaline Falls. Though their electric generation ended decades ago, the two dams still play an important role in recreation. Without the reservoirs they create, Sullivan Lake's summer pool would drop by nearly 25 feet, stranding public boat docks and leaving swimming beaches high and dry.