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Aquatic Connectivity and Barrier Removal

Restoring Free-Flowing Rivers in the Hudson River Watershed for Human and Fish Communities

A dam on the Mill Creek cuts off a family of ducks from trvaeling upstream
The first barrier from the Hudson on
the Mill Creek, City of Rensselaer, is a
barrier to many kinds of organisms.

Reconnecting Our Streams

Fish and many other organisms use rivers and streams as pathways to move between feeding, nursery and breeding grounds. Long stretches of connected stream habitat can be resilient to changes in climate and land use. Dams and many culverts are blocking those pathways and dramatically shrinking the habitat available. At the same time, dams and culverts that are too small affect hydrology, sediment transport, and water quality of streams, and cost money for towns and the state to replace and maintain.

A Student Conservation Association Excelsior Corps member records dimensions of a culvert
A Student Conservation Association Excelsior Corps
member records dimensions of a culvert. This culvert
is perched: water drops out of the structure and into
the stream, disconnecting the stream.

The Hudson River Estuary Watershed has more than 1500 dams, and likely more than ten thousand culverts. The Hudson River Estuary Program and many partners are working towards restoring free flowing tributaries to the Hudson River. Several projects are helping to prioritize which aquatic barriers are the most detrimental to our fish and human communities, so we can focus our limited resources at the most beneficial locations. Culvert assessments for 25% of the Estuary Watershed have been done so far. The map below shows where assessments have been done and what partners are working with the Hudson River Estuary Program on these barrier projects.

Dam Removal and Barrier Mitigation in New York State (PDF 3.49 MB) is a resource for private and municipal landowners with an interest in removing a dam or implementing an aquatic barrier mitigation project.

For the most up-to-date information about known aquatic barriers, please visit Cornell Water Resources Institute Aquatic Connectivity and Barrier Removal web page (link leaves DEC website). Please contact the Hudson River Estuary Program if you have any questions about dam removal, culvert mitigation, or aquatic connectivity.

A progress map of the Culvert Prioritization Project
Progress on the Culvert Prioritization Project, purple areas have
information available on culverts that are aquatic barriers.

Barrier Mitigation in the Hudson River Estuary Watershed

In the summer of 2016, 5 miles of upstream habitat was reconnected on the East Branch Wappinger Creek in Dutchess County with the removal of the Shapp Pond Dam. Watch a short video to learn more about the dam removal (link leaves DEC website).

More about Dam Removal and Culvert Mitigation