Ground-Water Recharge in the New Jersey Highlands Region

The Highlands of New Jersey currently supplies a third of the State's drinking water. For over a century runoff from this area has been the primary source of water for the major population centers of northeastern New Jersey. The Highlands Water Protection and Planning Act of 2004 defines the 'Highlands Region' and calls for significant restrictions on new development in order to protect its water resources. One factor that controls water resources is the amount of recharge that occurs in the Highlands Region. This recharge helps to define the carrying capacity, that is, how many inhabitants the region can support on a sustainable basis. The New Jersey Geological Survey's methodology of estimating ground-water is based on an average annual soil-moisture budget for the period 1957-1986. Applying this methodology to the Highlands Region yields an average annual ground-water recharge of 14.6 inches per year. Applying this methodology to the drought of record in New Jersey, the period 1961-1966, gives an estimated drought ground-water recharge of 9.8 inches per year. Four major watersheds drain the Highlands Region - Delaware, Passaic, Raritan and Wallkill. Average annual ground-water recharge estimates for these four watersheds are 14.1, 14.3, 16.3 and 13.8 inches per year, respectively. Drought annual groundwater recharge estimates for these four watersheds are 9.2, 10.2, 10.4 and 9.4 inches per year, respectively.N.J. Geological Survey Open-File Report 08-1Purpose: Quantify ground-water recharge in the New Jersey highland