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Research about Cumberland County, New Jersey

Source-linked reports with geographic coverage including Cumberland County, New Jersey.

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Stratigraphic and hydrologic relationship of the Piney Point aquifer and the Alloway Clay Member of the Kirkwood Formation in New Jersey

Coarse quartzose (clastic) sediments of middle and late Eocene age in the subsurface of southern New Jersey are identified in this report as the Piney Point aquifer. The sediments are as thick as 220 feet (67 metres) and form a freshwater aquifer which is laterally continuous with the Piney Point aquifer of the Delmarva Peninsula. The Piney Point aquifer, in the area of Newport in Cumberland County, consists of fine to coarse glauconitic sand that is suggestive of deposition in a marginal marine beach environment. The aquifer tends to become finer grained with depth; coarse sand is dominant near the top of the aquifer, whereas, silt and clay are dominant near the base. The top of the aquifer- is marked by an angular unconformity. The hiatus between the upper Eocene sediments and the overlying Kirkwood Formation of middle Miocene age represents erosion during Oligocene and early Miocene time. The Alloway Clay Member, the basal unit of the Kirkwood Formation, rests unconformably on the Piney Point aquifer. It is a silty clay, dark brown to light tan, and contains abundant shell fragments and reworked greensand from the underlying Piney Point aquifer. The Alloway Clay Member, where present, acts as a confining unit for the Piney Point aquifer in southern New Jersey. Chemical analyses of water samples from the Piney Point aquifer in Cumberland County indicate a potential chloride problem in the aquifer near Delaware Bay. A water sample taken in 1973 at the Gandys Beach well contained 516 milligrams per litre of chloride, and a water sample taken in 1973 at the Money Island Marina well contained 73 milligrams per litre of chloride. Scant water-level data indicate the possibility of declining water levels in Cumberland County near Delaware Bay due to pumping from the Piney Point aquifer in Delaware. The altitude of the water level at well 16 is -3 feet (-1 metre), and the water-level altitude at well 11 is +23 feet (+7 metres).

New Jersey

Ground-water resources: Cumberland County, New Jersey

Cumberland County is located in the Atlantic Coastal Plain physiographic province along the northeastern shore of Delaware Bay in Southwestern New Jersey. An average annual hydrologic budget was computed for Cumberland County. Water gains are: precipitation, 1,050 mgd (million gallons per day); surface-water inflow, 142 mgd; ground-water inflow negligible. Water losses are: evapotranspiration, 685 mgd; surface-water outflow, 370 mgd; ground-water outflow, 137 mgd. Unconsolidated and semiconsolidated Coastal Plain sediments, 2,500 to 4,500 feet thick, and ranging in age from Cretaceous to Holocene, consist of layers of clay, silt, sand and gravel. Aquifers composed mainly of sand and gravel occur in the Potomac Group and Raritan and Magothy Formations, the Wenonah Formation and Mount Laurel Sand, the Piney Point Formation, and the Kirkwood Formation and Cohansey Sand. Aquifers in the Potomac-Raritan-Magothy sequence contain saline water and are not currently utilized in Cumberland County. However, they may be utilized in the future for underground storage of fresh water, or possibly other uses when more is known about this aquifer system. The aquifer in the Wenonah Formation and Mount Laurel Sand is not presently utilized in Cumberland County. It is probably suitable for future development, however of wells yielding as much as 300 gpm (gallons per minute) of good quality water in the northern part of the county. The Piney Point Formation is tapped in Cumberland County by only a few wells; each of these generally yield less than 100 gpm. Additional small supplies can be developed from this aquifer. Water from this aquifer requires little or no treatment for domestic use. Two principal aquifers occur in the Kirkwood Formation and Cohansey Sand: (1) the lower Kirkwood aquifer and (2) the Cohansey-Kirkwood aquifer. Most wells tapping the lower Kirkwood aquifer yield less than 50 gpm but are capable of yielding as much as 400 gpm. Wells in the lower Kirkwood range in depth from 200 to 370 feet. The Cohansey-Kirkwood aquifer is the shallowest and most important source of ground-water in the county but is highly susceptible to surface contamination. This aquifer is highly permeable; analysis of data from two pumping tests indicates permeabilities of 1,200 and 2,700 gpm per square foot. It generally yields large supplies of water (300 to 1,200 gpm) to wells from depths of less than 180 feet. Water in the Cohansey-Kirkwood aquifer is characterized by 1mv dissolved-solids content (63 mg/l, median), low hardness (21 mg/l, median), and low pH values (5.5 pH units, median). Water use in Cumberland County varies and is highly seasonal, mainly because of increasing requirements for irrigation and the food processing industries in the county. In 1964 seasonal use ranged from 27 mgd in March to 145 mgd in August. This is much higher than withdrawals in neighboring Salem and Cape May Counties. In 1964 withdrawals in Cumberland County averaged about 51 mgd; almost all of this, 49.4 mgd, was from ground-water supplies. The total annual water use in 1964 according to type of use was: for public supply, 10.6 mgd; for industrial uses, 19.0 mgd; irrigation, 15.4 mgd; suburban, rural, residential, institutional, farm, and commercial, 5.9 mgd.

New Jersey