Water levels in major underground water sources in New Jersey were studied in 1983. The researchers measured water levels in over 1,000 wells and compared them to measurements from 1978. They found that increased pumping of groundwater has caused significant drops in water levels, creating large depressions in the underground water systems. The study identified specific areas, like Camden and Middlesex-Monmouth County, where water levels decreased by as much as 23 feet. In coastal areas, such as Monmouth and Ocean counties, water levels dropped by up to 29 feet. This decline is due to a connection between different underground water sources. Overall, the study shows that water levels in various aquifers in New Jersey have decreased significantly over the years due to increased water withdrawals.