The Zegrze Reservoir (or Zegrze Lake, in Polish officially Jezioro Zegrzyà Âskie, unofficially Zalew Zegrzyà Âski) is a man-made reservoir in Poland, located just north of Warsaw, on the lower course of the Narew river. It is formed by a dam constructed in 1963 with a hydroelectric complex producing 20 megawatts of power. The surface area of the reservoir is about 33 kmò. The name originates from the nearby Zegrze village, featuring the historic Radziwià Âà  Palace (Paà Âac Zegrzyà Âski) built in 1847 by the noble Krasià Âski family.