The Dämeritzsee is a lake located in Brandenburg and Berlin, Germany. At an elevation of 32 metres (105 ft), its surface area is 93.5 hectares (231 acres). It is located partly in the municipality of Erkner (Oder-Spree district) and part in Rahnsdorf, a Berliner locality in Treptow-Köpenick district.The lake forms part of the course of the River Spree, and is the location of that river's confluence with the short Flakenfließ that flows out of the Flakensee.