It was built in the spring Grahovsko part of the river, about 500m downstream from the springs. Land is built of dolomite . Height of the dam is 30m, the width of the crown of 3 m. Crown dam is 788.5 m n.v. Its length in this section is 171.5 m. Clean and clear water of the lakes used for irrigation, and construction of the filter and cleaner used for water supply. The lake is an important water reservoir for agricultural purposes Grahovo field, but also a place for sport, recreation and swimming in the summer months.