Greenwood Lake is located in Orange County, New York and Passaic County, New Jersey. Greenwood Lake, known as "Quampium" at the time, was purchased by the Europeans from the Minsis subtribe of the Lenni-Lenape Indians in 1707 and renamed "Long Pond". In 1765, a small dam was constructed to utilize the water power to run local iron mills.

The lake was extended again in 1836 by the creation of the dam located at Ringwood State Park which raised the water level 12 feet. The dam was built to supply water to the Morris and Essex Canal. These canals were traveled on by Pennsylvania coal barges, giving the lake a key role in the progress and development of the East Coast. The expansion of Greenwood Lake also attracted tourists to the area; however, the tourism rates dropped post-World War II and seasonal housing soon became permanent (Clean Lake Study, 1989).