South Branch River Restoration Project

Below is taken directly from the Raritan Headwaters Association’s website at https://www.raritanheadwaters.org/south-branch-river-restoration-project/

Cole’s Mill Dam 

Coles Mill Dam in Califon, NJ was constructed during the 1800s to power a gristmill., Credit: Steve Luell, USFWS

Raritan Headwaters Association (RHA) is collaborating with conservation partners, including the U.S. Fish and Wildlife Service, National Oceanic and Atmospheric Administration (NOAA), and NJ Department of Environmental Protection (NJDEP), to restore a section of the South Branch of the Raritan River through the proposed removal of the Cole’s Mill Dam in Califon, Hunterdon County, New Jersey. This project aims to restore habitat for fish and wildlife, improve water quality, and address local flooding. The dam, located on private property and originally built between 1830 and 1840, was later operated as a flour mill but has since become obsolete. Over time, the reach of the river impounded by the dam has become shallow and often has poor water quality in the warmer months of the year, causing degraded habitat for fish and other wildlife, both above the dam and downstream.  Following a partial breach of the dam in 2018, the NJDEP Bureau of Dam Safety mandated either its repair or removal. The property owner bears the responsibility for the dam’s liability, financial management, and maintenance, and was faced with the decision  whether to undertake the costly repairs or proceed with removal and restoration of the natural river. The landowner is working cooperatively with the project team to implement the restoration, which  includes removing the dam, stabilizing and strategically planting adjacent streambank and riparian areas, managing upstream sediments, and implementing scour protection measures to protect nearby property and infrastructure. The project will also include monitoring during the period after construction to ensure successful establishment of the new river channel and corridor.

The project is being funded by the settlement associated with the natural resource damage assessment and restoration claim for the Cornell-Dubilier Electronics (CDE) Superfund Site in South Plainfield, New Jersey. The Califon (Cole’s Mill) Dam Removal project is  one of 20 projects selected through a watershed-wide scoping effort that took place to solicit project ideas that would restore or replace natural resources that were injured as a result of the release of hazardous substances at the CDE Site. All projects were evaluated and selected in a restoration plan that went out for public comment and was finalized in August of 2021. Now, the Natural Resource Trustees for the CDE Site (NJDEP, NOAA, USFWS) are working with partners to implement these projects, in this case, RHA and Princeton Hydro, who are contracted to conduct the feasibility, engineering, and design for the project.

Public outreach efforts have begun to engage the Califon Borough community and gather input on the project as it moves forward. Technical investigations and feasibility studies are currently underway to assess the impacts of the project, which will help determine the best course of action. The project team plans to continue to accept feedback and engage with members of the community as the project advances. 

While the project may lead to changes in the local environment and viewshed, there will be many long-term benefits. The removal of the Cole’s Mill Dam is expected to bring significant environmental and recreational enhancements, including improved fish and wildlife habitat, enhanced water quality, and a safer, free-flowing river that will remain a focal point of the Borough of Califon. Regulatory oversight and approval from multiple agencies, including the NJDEP Bureau of Dam Safety, will be required before the project can proceed, ensuring that any potential impacts, including those related to flooding and historical resources, are carefully managed.

Please review this list of Frequently Asked Questions and the resources shared below for more information. This dam removal and associated restoration  are part of a state-wide and national movement to restore degraded river ecosystems. To learn more about this, see links below.

Last modified: October 18, 2024