Lake Cumberland is a reservoir in Clinton, Pulaski, Russell, Wayne, and Laurel, counties in Kentucky. The primary reasons for its construction were a means for flood control and the production of hydroelectric power. Its shoreline measures 1,255 miles and the lake covers 65,530 acres at the maximum power pool elevation. The reservoir ranks 9th in the U.S. i…Lake Cumberland is a reservoir in Clinton, Pulaski, Russell, Wayne, and Laurel, counties in Kentucky. The primary reasons for its construction were a means for flood control and the production of hydroelectric power. Its shoreline measures 1,255 miles and the lake covers 65,530 acres at the maximum power pool elevation. The reservoir ranks 9th in the U.S. in size, with a capacity of 6,100,000 acre-feet of water, enough to cover the entire Commonwealth of Kentucky with 3 inches of water. The main lake is 101 miles long and over one mile across at its widest point.