Primary inflows Surface elevation 12 m Inflow source Hackensack River | Surface area 1,255 acres (5.08 km) Area 5.079 km² Lake type Reservoir | |
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Location Bergen County, New Jersey and Rockland County, New York, United States Basin countries Newark Basin
United States Water volume 3,500,000,000 US gal (13,000,000 m) | ||
Lake Tappan is a reservoir impounded by the Tappan Dam on the Hackensack River, straddling the border between the U.S. states of New Jersey and New York. Within New Jersey, the lake traverses the border separating the municipalities of River Vale and Old Tappan in Bergen County, while extending northward across the New York state line into the town of Orangetown in Rockand County. The reservoir was formed in 1967, flooding areas that included the former CAPROC Field Civil Air Patrol airstrip.
Map of Lake Tappan, United States
The Lake Tappan reservoir covers 1,255 acres (5.1 km²), the majority of its area within New Jersey, and contains 3.5 billion US gallons (13,000,000 m3) of water, with up to 12 to 13 million US gallons (45,000 to 49,000 m3) released downstream daily into the Oradell Reservoir, which lies entirely within Bergen County in New Jersey. The passage of this water between reservoirs can occur in as rapidly as two to three hours.
On March 11, 2003, New Jersey Governor Jim McGreevey visited the reservoir and proposed protecting it as well as the nearby Woodcliff Lake Reservoir and their tributaries with Category 1 water purity status.
The reservoir is owned by United Water, a private utility.
Lake Tappan is a local fishing spot as well, serving as a habitat for bluegill, bass, perch, catfish and carp.