Kirkwood-Cohansey Aquifer: South Jersey’s Water Supply

The Kirkwood-Cohansey Aquifer is the source of drinking water and water in our rivers and lakes.

SHARE:

South Jersey is made up of three distinct ecological regions: the Bayshore, the Pinelands, and the outer coastal plain along the Atlantic coast, all of which are uniquely tied to water. Between the Delaware Bay, the ocean, and the many rivers and streams that crisscross our landscape, there’s a lot of water all around us. But there may be even more than you realize.

The Kirkwood-Cohansey Aquifer holds 17 trillion gallons of fresh, clean water beneath your feet, running in your tap, flowing through your communities and it covers almost a third of the state! An aquifer is an underground sediment layer that can store and move water through the ground. The Kirkwood-Cohansey aquifer is a superficial aquifer, which means the water table is close to the land surface and that surface and groundwater are connected.

Ninety percent of the water in South Jersey wetlands, creeks, rivers and lakes is water that flows out of the ground from the Kirkwood-Cohansey aquifer. ©Robert Barnes

The aquifer provides drinking water for about one million people in South Jersey. Chances are when you turn on your faucet or hose, the coffee pot, the shower, or the garden hose, that’s Kirkwood-Cohansey Aquifer water. The aquifer is also the source of water for farmers, who use it to irrigate hundreds of thousands of acres of cropland every year. It’s not just Jersey-fresh produce that relies on the aquifer — businesses all across South Jersey, from breweries to hospitals and food processors and manufacturing businesses need an abundant and clean water supply to thrive.

Most water in wetlands, lakes, streams, and rivers in southern New Jersey is water that seeps or flows directly from the ground from the Kirkwood-Cohansey aquifer.

kirkwood-cohansey aquifer map

By supplying the water that flows through its rivers and streams, the aquifer also provides critical, fresh water to coastal estuaries, like Barnegat Bay, and to the Delaware River and Delaware Bay. Rivers that flow into the Atlantic Coast estuaries from the Kirkwood-Cohansey aquifer include the Mullica River, Great Egg Harbor River, Oyster Creek and dozens more. The Rancocas Creek gathers water from a broad area and flows into the Delaware River above Philadelphia and Camden. The Maurice and Cohansey Rivers flow south from the aquifer into Delaware Bay. In these ways, the aquifer sustains water supply and ecosystems far beyond its own boundary.

kirkwood cohansey aquifer illustration aquifers of new jersey

Because it is so shallow, it is easily polluted by fertilizers, herbicides, pesticides and chemicals that are spread or spilled on the ground’s surface. Also, over-pumping or excessive withdrawals of fresh water harms wetlands and unique plant and animal species that rely on the special characteristics of pure Kirkwood-Cohansey water.