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Dam Removals: Gruendyke

MWA led the effort to remove the badly deteriorated Gruendyke Mill dam that partially blocked the Musconetcong immediately upstream from the Route 46 bridge at the border of Hackettstown and Mount Olive Township.  The Gruendyke Mill dam was one of the many obsolete dams blocking the river.  The removal of this dam was the first step in a long-term effort to restore the river's natural flow, improve water quality and enhance fish migration.

Dams and the pools behind them may make a pretty scene to the casual observer with geese floating about amid lovely purple loosestrife flowers and the phragmites that look like feathered cattails.  However, that lovely scene reveals a local environmental mess.  When the dams were built they created an artificial pool that changed the local landscape.  Native plant, fish and bird species lost their natural home.  The pool of standing water created by the dam replaced wetlands, river banks and marshes that could no longer support the flora and fauna that formerly thrived there.  Removing a dam is the first step in restoring the natural environment.

In March 2008, the first notch was cut in the Gruendyke Dam.  On June 16, 2008 removal of the Gruendyke Dam began.

The June 16, 2008 removal of half of the dam revealed something that we never could have guessed.  For the most part, the consequences of damming our rivers are invisible.  High temperature, concentrated pollutants and lower oxygen degrade aquatic habitat.  Which is why river bank restorations and clean-ups are important after any dam removal.

An Emergency clean-up coordinated by Brian Cowden, Trout Unlimited Musconetcong Home Rivers Initiative Coordinator, was held on June 25, 2008 to remove the tires and other debris that were revealed under the former Gruendyke Mill Dam pool.  Trout Unlimited members came out in force from several chapters to help.  MWA Trustees and members, NJ hatchery workers, family of dam owners Rodger and Eileen Cornell and many others came out to help.  Lunch for the volunteers was provided by the Pump House Restaurant.  The entire project is in full view of the outside eating area at the Pump House Restaurant, 2 Highway 46 Hackettstown, NJ 07840.

For an informative video developed by the Hydropower Reform Coalition on the environmental and social impacts of dams on our waterways go to

For information about dam removals across the county check out Clearinghouse for Dam Removal Information

Other Projects





Warren Glen

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