National

Aquatic Barrier Inventory & Prioritization Tool

Aquatic Barrier Tool

Photo: John Holm

Northeast Region

Northeast region map
Map of 29,595 inventoried dams and 67,250 road-related barriers likely to impact aquatic organisms in the Northeastregion.

Includes 11 states and Washington DC with:

29,595 inventoried dams, including:

  • 158 that have been reconned for social feasibility of removal
  • 1,009 that have been removed or mitigated, gaining 17,160 miles of reconnected rivers and streams

458,178 or more potential road-related aquatic barriers, including:

  • 121,578 that have been assessed for impacts to aquatic organisms
  • 67,250 that are likely to impact aquatic organisms
  • 142 that have been removed or mitigated, gaining 398 miles of reconnected rivers and streams

Progress toward restoring aquatic connectivity:

year removed
show:miles gained|number removed
2024
16 miles
2023
708 miles*
2022
1,060 miles
2021
331 miles*
2020
244 miles*
2010-2019
4,946 miles*
2000-2009
5,398 miles*
before 2000
2,736 miles*
unknown
2,119 miles*
dams
road-related barriers
* includes 49 dams and / or road-related barriers that could not be correctly located on the aquatic network or were otherwise excluded from the analysis; these contribute toward the count but not the miles gained.
Note: counts above may include both completed as well as active barrier removal or mitigation projects.
Explore how many dams or road-related barriers there are in a state, county, or watershed.
Explore dams and road-related barriers that have been removed or mitigated by state, county, or watershed.
Identify and rank dams or road-related barriers that reconnect the most high-quality aquatic networks.

Statistics by state:

Inventoried damsReconned damsAssessed road-related barriers
Connecticut4,369295,001
Delaware132058
District of Columbia1214
Maine1,0571023,993
Maryland1,209283,159
Massachusetts3,05537,475
New Hampshire4,729020,370
New Jersey1,95202,352
New York7,5456033,132
Pennsylvania3,8122510,586
Rhode Island6460598
Vermont1,077214,850
Total29,595158121,578

6,324 inventoried dams and 33,225 assessed road-related barriers were not analyzed because they could not be correctly located on the aquatic network or were otherwise excluded from the analysis. You can optionally include these in your download.

Note: These statistics are based on inventoried dams and road-related barriers. Because the inventory is incomplete in many areas, areas with a high number of dams may simply represent areas that have a more complete inventory.


You can help!

You can help improve the inventory You can help improve the inventory by sharing data, assisting with field reconnaissance to evaluate the impact of aquatic barriers, or even by reporting issues with the inventory data in this tool.

Contact us to learn more about how you can help improve aquatic connectivity in the Northeast region.