top of page

Cedar Grove Dam Removal

Project Purpose:

Removal of the Cedar Grove dam from the Pequest River will amplify the impact that the removal of the three most downstream dams (work currently in progress) will have on restoring aquatic connectivity and improving water quality for the benefit of Delaware
River Basin (DRB) trust species. Dam removals yield important ecological benefits, increase recreational opportunities, and can reduce public safety risks. These benefits are magnified when seen through the lens of climate change: dam removals will help ensure that fish and wildlife corridors are connected as species are forced to migrate, and they contribute to the restoration of
floodplain functionality, which is increasingly important in light of more frequent and intense storms. A limited number of dam removal experts is inhibiting the pace of removals and the accompanying ecological benefits in the DRB. In addition to the ecological benefits, this project also engaged with new engineering and construction firms and is providing them with experienced advisors, and in turn this project is helping to build dam removal capacity in the Delaware River Basin and throughout New Jersey.

 

Brief Description:

We are requesting $25,000 to help cover a portion of construction costs. This project is funded in part via NFWF’s Delaware Watershed Conservation Fund (NFWF-DWCF total $266,060) and with private funding via TNC’s donors ($269,493). This project is the fourth in a series of removals on the Pequest River and we are working with a “new to dam removal” engineering firm, EHS Support on the engineering design and permits. We anticipate hiring a new construction firm next summer to lead the construction work. Currently, our NFWF-DWCF funding ends November 2024 and so it is critical that we complete all construction activities by
the November deadline.


Resource Values/Project Outputs:

In 2021, The Nature Conservancy (TNC) in New Jersey began to advance the removal of two dams on the Pequest River, the Upper and Lower E.R. Collins Dams. These two dams are within 1,500 feet of the confluence of the Delaware River and, in addition to blocking fish migration and degrading instream habitat, contribute to the flooding of homes and businesses in the town of Belvidere. Removal of the Upper and Lower E.R. Collins Dams will help to reconnect approximately three miles of stream for migratory fish to return to their historic spawning runs, improve water quality for resident fish and other aquatic species, enhance recreational opportunities for anglers and paddlers, and help to mitigate flooding in downtown Belvidere. TNC proposes to build upon the restoration impact of these removals, by continuing this critical conservation work further upstream; removal of the next two dams, the No Name and Cedar Grove Dams, will open an additional 57.8 miles on the main stem Pequest River (7.8 miles) and its nearby tributaries (50 miles). The No Name and Cedar Grove Dams, both of which are privately owned, are in poor condition and partially breached; all landowners would like to pursue dam removal. Once the three existing downstream barriers (E.R. Collins Dams and No Name) are removed, the Cedar Grove Dam will become one of the highest priorities for removal in the Northeast in terms

of its importance to reconnecting critical habitat (tier 1, severe barrier) according to the Northeast Aquatic Connectivity Tool Analysis
(Martin, E. H. and J. Levine. 2017. Northeast Aquatic Connectivity Assessment Project - Version 2.0: Assessing the ecological impact of barriers on Northeastern rivers. The Nature Conservancy, Brunswick, Maine). The removal of these two dams, in addition to the two E.R. Collins Dams, would open approximately 10.8 miles along the mainstem, and reconnect 50 miles of nearby tributaries for resident and migratory fish and other aquatic organism. Specifically, these removals will restore and reconnect habitat for diadromous fish species listed in the 2015 New Jersey State Wildlife Management Plan: American shad (Alosa sapidissima), blueback herring (Alosa aestivalis), alewife (Alosa pseudoharengus), American eel (Anguilla rostrata) and native sea lamprey (Petromyzon marinus). Also, these removals will help to improve water quality and allow for new and increased recreational opportunities on the Pequest River.


Cost/Budget: $25,000

Total Cost for Cedar Grove removal project is estimated to be $419,080.00. The $25,000 in CWRP will be used only for construction costs associated with this project. Other activities for this removal project as well as the No Name Dam removal will be covered by the NFWF-DWCF grant ($266,060) and TNC private funding ($269,493).


Activities Total Cost:

  • Freshwater Mussel Monitoring - $2,500

  • Engineering - $226,580.00

  • Construction Estimates - $190,000.00

  • Total - $419,080.00

Schedule: Initiation of project in month/year - a timetable for completion of 10 months

 

Activity (for each dam removed) and Time Period (proposed):

 

  • Pre-Application Meetings with Regulators - August 2023 

  • Data Collection and Review; Field Survey, Base Mapping, and Bathymetry (*includes initial freshwater mussel surveys) - June –August 2023

  • Engineering Design: Hydraulic & Hydrologic; Fish Passage Assessment - August – September 2023 

  • Engineering Design: Preliminary Engineering Design Plans (60%) - September – November 2023

  • Engineering Design: Final Engineering Design Plans (100%) - June 2024

  • Submission of Permit Package to Regulatory Agencies - November 2023

  • Anticipated Receipt of Permits - June 2024 

  • Bid Process - May – June 2024

  • Construction - July – Nov 2024 

  • Construction Oversight - July – Nov 2024

 

Permit Status: Application submitted November 2023

 

List of Partners: USFWS, Princeton Hydro

 

What is requested from the CWRP/Contribution: $25,000

 

Point of Contact: Michelle DiBlasio, (908)955-0342, michelle.diblasio@tnc.org

 

Map: Pequest Watershed with the four dam removals TNC is working on, including the Cedar
Grove Dam which is shown by the red triangle below.

Screenshot 2024-05-02 at 10.16.32 AM.png
bottom of page