The Obersee near Simmerath in the borough of Aachen is the main forebay of the Rur Reservoir on the River Rur in the Eifel mountains of Germany. Its barrier is the Paulushofdamm. The reservoir, like that of the Rur Dam, belongs to the Eifel-Rur Water Company (Wasserverband Eifel-Rur). The reservoir provides drinking water.