National

Aquatic Barrier Inventory & Prioritization Tool

Aquatic Barrier Tool

Photo: Adam Bouse

Great Lakes Region

(in development)
Great Lakes region map
Map of 15,573 inventoried dams and 10 road-related barriers likely to impact aquatic organisms in the Great Lakesregion.

Includes 7 states with:

15,573 inventoried dams, including:

  • 30 that have been reconned for social feasibility of removal
  • 695 that have been removed or mitigated, gaining 18,338 miles of reconnected rivers and streams

867,994 or more potential road-related aquatic barriers, including:

  • 10 that have been assessed for impacts to aquatic organisms
  • 10 that are likely to impact aquatic organisms
Explore how many dams or road-related barriers there are in a 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
Illinois1,62810
Indiana1,09000
Iowa4,4312710
Michigan1,07110
Minnesota1,23910
Ohio1,44900
Wisconsin4,66500
Total15,5733010

2,575 inventoried dams and 0 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 Great Lakes region.