The Besaya River Basin is the largest in the region of Cantabria, covering about 396 square miles (1,030 km2). The region annually receives 0.3 cubic miles (1.3 km3) of precipitation. The Besaya River flows north into the Bay of Biscay. In some stretches of the river, the V-shaped valley and steep slopes lend themselves to dams that generate electricity. The lower sections of the river are prone to flooding.