Most of the county's borders are rivers. The Pequannock River drains the northern boundary area. The Pompton River drains the eastern section. The Passaic River also drains the eastern border area. The western border is drained by the Musconetcong River. There are several large lakes in Morris County; among them are the state's largest lake, Lake Hopatcong, Budd Lake, Lake Parsippany, and the Boonton Reservoir, also known as the Jersey City Reservoir.
Most of the county's borders are rivers. The Pequannock River drains the northern boundary area. The Pompton River drains the eastern section. The Passaic River also drains the eastern border area. The western border is drained by the Musconet.cong River There are several large lakes in Morris County; among them are the state's largest lake, Lake Hopatcong, Budd Lake, Lake Parsippany, and the Boonton Reservoir, also known as the Jersey City Reservoir.