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Project Purpose:  The goal of the project is to restore approximately 5.5 miles of the Millstone River to migratory fish spawning in Hillsborough and Franklin Townships, Somerset County, New Jersey.   


Brief Description:  The dam is owned by the New Jersey Department of Environmental Protection (NJDEP) and is the second blockage on the Millstone River.  The first blockage, the Weston Causeway Dam is currently being considered for dam removal.  The existing Blackwells Mills Dam is a concrete dam was likely constructed in early 1900s and is 5 feet high and 90 feet wide.  Breaching the Blackwells Mills Dam would involve removal of approximately 90 feet of total structure and stabilizing and restoring approximately 500 feet of the Millstone River upstream of the dam.  Only the spillway of the dam will be removed; the abutments, remains of the original mill, and the remnant millstones will not be disturbed in order to preserve historic structures.  The Blackwells Mills Dam flows directly into the Raritan River and then the Raritan Bay, a priority restoration site. 


Resource values / Project Outputs: The proposed project would involve breaching the dam to restore approximately 9 miles of migratory fish spawning habitat, which will include restoration of 1.7 miles of natural stream habitat in the Millstone River.  The primary target fish include American shad, alewife, blueback herring, and American eel.  In addition, restoring stream connections within the Millstone River will improve habitat for a variety of wetland dependent wildlife including a variety of warblers, wood duck, woodcock, and flycatchers. 


Cost/Budget: $125,000.00 total budget


Schedule: Construction anticipated for Summer to Fall 2013, once all permits are secured. 


Permit Status: On-going


List of Partners: U.S. Fish and Wildlife Service, NJDEP, Stony Brook Millstone Watershed Organization, NOAA, American Rivers.

What is requested of CWRP: $25,000 to contribute to the restoration effort.  Specifically funds will be used for mitigation of impacts to historical resources and for required adjustments to the USGS Gage at Blackwells Mills.  The Watershed will be required to mitigate for the impacts to the dam and its impoundment- most likely through development and erection of signage and the presence of a historian on site during the removal to document any artifacts that are exposed.  In addition, the Watershed will be required to cover costs associated with adjustments to the USGS Gage at Blackwells Mills, through relocation of the intake instruments for the gage and/or recalibration of the gage.

Blackwells Mills Dam Removal

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