Warren County will soon have one less lake.

Starting Monday, the state environmental department is scheduled to begin drawing water from Columbia Lake in Knowlton Township, dropping the level about a foot a day until it can remove structures including the dam that formed the lake on the Paulins Kill.

Destruction of the 18-foot high, 330-foot long Columbia Lake Dam will allow shad and eels to move more freely toward spawning grounds, according to the New Jersey Department of Environmental Protection, which has owned and managed the dam within the 1,098-acre Columbia Wildlife Management Area since 1955.

The dam is about a quarter-mile up the Paulins Kill from the confluence with the Delaware River. The lake itself covers 43 acres.

The dam was built in 1909 by the Warren County Power Co. to harvest ice and supply energy, according to the DEP and The Nature Conservancy, which is leading the project as part of a larger plan to improve the Paulins Kill watershed. By slowing the water's flow, the dam creates warm ponds where sediment fills in, detracting from the overall health of the waterway, the conservancy says.

The area around the lake will be closed to the public during the work. Fish and mussels will be removed during the drawdown and relocated to the Delaware River, the DEP said in an email announcement.

(MORE INFO: A state summary of the dam removal project)

Once the lake is drained, the removal of a smaller "remnant dam" downstream from the main dam is expected to commence about June 18. After that, an old powerhouse will be demolished, followed by the Columbia Lake Dam itself. In the fall, modifications to an I-80 culvert may be needed to allow shad and other fish to pass.

Officials in Knowlton Township have had a number of complaints with the DEP over the last several years, and this project is no exception. In 2016, the township's elected leaders criticized the dam-removal plan, saying the lake is an attraction for outdoor activities and was used by firefighters as an emergency water source.

Steve Novak may be reached at snovak@lehighvalleylive.com. Follow him on Twitter @type2supernovak and Facebook. Find lehighvalleylive.com on Facebook.