Also called Černá Desná dam. Its construction was started almost at the same time as the dam at Bílá Desná, but after a breach occured in its walls its lake was emptied and not reffiled until the years 1925-1927. After World War II the construction of the large recreation centre was started here, but in the early Seventies Souš was changed into reservoir of drinking water for Jablonec nad Nisou and Tanvald.