Imuruk Lake (Inupiaq:àImaáruk or Narvaáruk) is the largest body of fresh water in Seward Peninsula in the U.S. state of Alaska. It measures and has a drainage basin of , It lies on top of a lava plateau at an elevation of . The drainage basin is relatively flat, as the maximum elevation is only about . A low gap in the divide between the lake and the head of the right fork of Goodhope River rises only a few feet above the lake. The Fairhaven Ditch takes practically all its water from the lake. Serpentine Hot Springs flow to the Serpentine River, northwest of Imuruk Lake.