Project Description
The Rockafellows Mills Dam, located on the border of Readington and Raritan Townships in NJ, is a 14-foot high concrete and rock-fill dam. The date it was first constructed is unknown, but it was rebuilt in 1919 to power a small mill. Dam failures had been recorded in 1930 and 1978 though all of the damage has since been repaired. The dam is the downstream-most barrier to fish passage on the South Branch Raritan River. It forms a 12.5-acre impoundment that has become shallow due to sediment accumulation. This has also led to an increase in water temperature and decline in overall water quality in the impoundment and downstream of the dam.
The proposed restoration activities include removing the Rockafellows Mills Dam, managing the upstream sediments, and restoring the riparian corridor by stabilizing the shoreline and planting native vegetation. In combination with the intended removal of the Headgates Dam and improvements to fish passage at Island Farm Weir, the removal of this dam would improve aquatic connectivity and allow migratory fish, such as American eels, river herring, and striped bass, to access approximately 55 miles of the mainstem and South Branch from Raritan Bay to Clinton, NJ. The improvements to aquatic habitat would benefit trout and other coldwater fish, as well as several species of freshwater mussels. The removal of the Rockafellows Mills Dam will also enhance recreational kayaking and canoeing on the river.
In 2023, 16 acres of land including the dam was purchased and preserved in perpetuity, transitioning from private ownership to public open space. The CDE Trustees coordinated with the purchasing parties to initiate the transaction that sets the dam removal process in motion. In all, eight conservation partners were involved in seeing this effort through. The dam removal and restoration project is ongoing and will include a feasibility study, engineering and design, permitting, construction, and restoration monitoring.
Parties Implementing Restoration
New Jersey Department of Environmental Protection; NOAA; Raritan Headwaters Association; U.S. Fish and Wildlife Service
DOI Project Representatives
Fish and Wildlife Service