 The borough borders the Bergen County municipalities of Dumont, Emerson, Haworth, New Milford, Paramus and River Edge.Oradell Reservoir was formed by the Oradell Reservoir Dam placed on the Hackensack River, which was started in 1921 and finished in 1923.The reservoir is fed by the Pascack Brook and Dwars Kill in addition to the Hackensack River.