Lake Information for Round Valley Reservoir

Round Valley Reservoir in Clinton Township was formed in 1960 when the New Jersey Water Authority constructed two large dams and flooded a volcanic crater in the state's Hunterdon County. The Reservoir is named after the naturally formed circular valley surrounded by Cushetunk Mountain. The deep Valley was caused by erosion of the soft sedimentary rock that had filled in the crater. The surrounding ridges of Cushetunk Mountain endure because they were underlaid with dense and durable volcanic rock diabase that cooled slowly under the surface of the earth.

Reaching depths of 180 feet, this 2,000-acre (8 km²) reservoir is best known for its pristine clear blue waters. The reservoir contains 55 billion gallons of water for use in central New Jersey, and is distributed during times of drought via the nearby south branch of the Raritan River . The New Jersey Division of Wildlife (a department of the New Jersey Department of Environmental Protection) claims the reservoir is the southernmost body of water that contains naturally reproducing lake trout. The park also has a wilderness area for camping, swimming facilities, a boat ramp and nature hiking and biking trails.

The reservoir has been called the Bermuda Triangle of New Jersey, and over 25 people have drowned there since 1971. 6 of them have never been found.