New Jersey Aquifer System
The New Jersey Aquifer System refers to the interconnected network of underground water-bearing rock formations and sediment layers that extend throughout New Jersey and supply a significant portion of the state's freshwater resources. These aquifers, which include the Potomac-Raritan-Magothy aquifer system, the Kirkwood-Cohansey aquifer system, and several regional formations, represent critical infrastructure for public water supply, agricultural irrigation, and industrial processes across the state. The aquifer system is geologically complex, with water-bearing strata ranging from Cretaceous-age formations to more recent unconsolidated sediments, varying in depth from near the surface to over 1,000 feet below ground level. New Jersey's reliance on groundwater aquifers is substantial, with approximately 40 percent of the state's population depending on groundwater for drinking water supply, making the management and protection of these aquifers essential to the state's environmental and economic health.[1]
Geography
The New Jersey Aquifer System extends across multiple hydrogeologic provinces that reflect the state's diverse geological history. The most significant aquifer formations include the Potomac-Raritan-Magothy (PRM) system, which underlies a large portion of central and southern New Jersey and consists of three distinct aquifer units separated by confining clay and silt layers. This system extends from northern Middlesex County southward into Atlantic and Burlington Counties, with the aquifer units dipping progressively deeper toward the coast. The Kirkwood-Cohansey aquifer system, located primarily in southern New Jersey, comprises multiple sandy units that are generally unconfined near the surface and become confined at greater depths. These formations collectively represent one of the most productive aquifer systems in the northeastern United States, with yields in some areas exceeding 1,000 gallons per minute in individual wells.
The geographic distribution of New Jersey's aquifers reflects the state's position at the margin of the Atlantic Coastal Plain. In northwestern New Jersey, Paleozoic bedrock formations containing limited groundwater supplies underlie the ridge and valley topography. Moving eastward and southward, younger Mesozoic and Cenozoic sedimentary formations become increasingly important sources of groundwater. The depth to water in New Jersey aquifers varies considerably by location, ranging from less than 10 feet below the surface in some coastal and inland areas to over 300 feet in other regions. The hydraulic properties of the aquifer system, including transmissivity and storativity, also vary significantly among formations, with confined aquifers generally exhibiting higher transmissivity values than unconfined units.[2]
History
The scientific understanding of New Jersey's aquifer system developed gradually over the twentieth century as groundwater became increasingly important to the state's water supply. Early investigations in the 1920s and 1930s by the United States Geological Survey (USGS) identified major aquifer formations underlying central and southern New Jersey, establishing the foundation for hydrogeologic research in the state. These pioneering studies documented the extent and productivity of the Potomac-Raritan-Magothy aquifer system, demonstrating that vast quantities of freshwater could be extracted from deep sedimentary formations. The recognition of these renewable groundwater resources encouraged agricultural development and municipal water supply expansion throughout the twentieth century.
Intensive groundwater development accelerated after World War II, with New Jersey communities increasingly turning to aquifer systems to meet growing water demands. By the mid-twentieth century, groundwater supplied water to numerous municipalities and agricultural operations, particularly in areas lacking surface water sources. However, increased withdrawals also led to documented problems including aquifer depletion, saltwater intrusion in coastal regions, and groundwater quality degradation from industrial and agricultural contamination. The recognition of these challenges prompted the New Jersey Department of Environmental Protection, established in 1970, to implement comprehensive groundwater monitoring programs and regulatory frameworks. The Comprehensive Statewide Groundwater Protection Act of 1983 represented a major policy initiative to address contamination and ensure sustainable use of aquifer resources. These regulatory developments reflected growing awareness of the aquifer system's importance and vulnerability to both depletion and contamination.[3]
Economy
The New Jersey Aquifer System supports substantial economic value through its provision of freshwater for municipal supply, agricultural use, and industrial processes. Approximately 2 billion gallons per day of groundwater are withdrawn from New Jersey aquifers annually, supporting public water systems serving millions of residents and visitors. The cost of developing alternative water supplies through desalination, surface water treatment, or importation would far exceed the value of aquifer-derived groundwater, making groundwater development central to the state's water supply economics. Many municipalities, particularly those in central and southern New Jersey lacking reliable surface water sources, have developed comprehensive groundwater-dependent infrastructure representing substantial capital investment.
Agricultural operations in southern New Jersey, historically the state's agricultural heartland, depend significantly on aquifer system water for irrigation and livestock watering. Horticultural operations, cranberry and blueberry farming, and vegetable production all require substantial water supplies that groundwater has traditionally provided. Industrial facilities, including food processing plants, chemical manufacturers, and pharmaceutical operations, also utilize groundwater for production processes and cooling water. The economic value derived from these agricultural and industrial uses, combined with the cost avoidance of developing alternative water supplies, demonstrates the aquifer system's critical importance to the state's economy. Water utilities operating throughout New Jersey maintain groundwater extraction infrastructure and monitoring systems representing billions of dollars in accumulated investment, underscoring the economic significance of sustainable aquifer management.[4]
Education
Research institutions throughout New Jersey have contributed significantly to understanding the state's aquifer system through hydrogeologic investigation and water resource management studies. Rutgers University, the New Jersey Institute of Technology, and Princeton University have conducted extensive groundwater research addressing contaminant transport, aquifer characterization, and sustainable water supply management. These academic investigations have informed state policy decisions and provided technical expertise supporting aquifer protection initiatives. University researchers collaborate regularly with the USGS New Jersey Water Science Center, which maintains long-term groundwater monitoring networks and conducts detailed hydrogeologic assessments of aquifer systems.
Professional education and training in groundwater science, hydrogeology, and water supply engineering are available through multiple New Jersey institutions, preparing professionals to manage the state's groundwater resources. Professional licensing requirements for groundwater professionals, including hydrogeologists and water supply operators, ensure that individuals managing aquifer systems possess appropriate technical knowledge and qualifications. Public education initiatives by the New Jersey Department of Environmental Protection, county cooperative extension services, and environmental organizations promote awareness of aquifer protection among landowners, farmers, and municipal officials. Educational programs addressing groundwater contamination prevention, proper well construction and maintenance, and sustainable water use practices have contributed to improved groundwater stewardship throughout the state.