Elektrėnai Reservoir (Lithuanian: Elektrėnų marios), located south of the city of Elektrėnai, Lithuania, is the third-biggest artificial lake in Lithuania. It was created in 1961 by damming the Strėva River. It supplies cooling water to the 1,800 MW Elektrėnai Power Plant. A number of villages were drowned by the reservoir; over 140 of them were relocated.