Skjerjavatnet is a lake on the border of the municipalities of Vaksdal and Modalen in Vestland county, Norway. The 7.37-square-kilometre (2.85 sq mi) lake sits at an elevation of 964 metres (3,163 ft) above sea level, in the mountains between the Modalen and Eksingedalen valleys. The southwest and northeast ends of the lake are both dammed up so that the lake can be regulated for hydroelectric power.