In early June, 2018, NJDEP Fish and Wildlife began the drawdown of Columbia Lake, located within the Columbia Wildlife Management Area 1/4 mile upstream of the Paulins Kill River’s confluence with the Delaware River in Knowlton Township, Warren County. The drawdown was in preparation for the removal of the obsolete dam which blocked American Shad to their historic spawning grounds, and impedes the movement of American Eel.

The 18-foot high, 330-foot long dam was constructed in 1909 by Warren County Power Co. and impounded a 43-acre lake that stretched more than 1.5 miles upstream of the dam. The dam and the lake (sold by NJ Power & Light Co. in 1955) became part of the 1,098 acre Columbia WMA.

The removal of the dam now allows fish passage to more than 10 miles of river by restoring the natural flow regime, and it reclaims 1.5 miles of stream habitat. The project has caused the area of the lake to remain closed to the public. The area is patrolled and trespassers will be prosecuted. The river below Warrington Road is also closed to all boating.

The dam removal project is just one aspect of a larger initiative led by The Nature Conservancy with the goals of improving riparian and in-stream habitat throughout the Paulins Kill watershed.

A Tale of Two Fishes: Removing the Columbia Dam – The Nature Conservancy, January 2019