A census of fish passage facilities at US hydropower developments across the conterminous United States

Journal Article · Fri Jul 18 00:00:00 EDT 2025 · Journal of Environmental Management

DOI:https://doi.org/10.1016/j.jenvman.2025.126623· OSTI ID:2574467

Matson, Paul G. ^[1]; Bozeman, Bryan B. ^[1]; DeRolph, Chris R. ^[1]; Oladosu, Gbadebo A. ^[1]; Singh, Debjani ^[1]; Richie, Diandre ^[1]; Morales, Jesus ^[2]; Pica, Jessica ^[2]; Sojkowski, Bryan ^[2]; Lake, Bjorn A. ^[3]; Anderson, Nicholas B. ^[3]; Bellerud, Blane ^[3]; Dionson, Simon ^[3]; Ames, Shannon ^[4]; Fischer, Maryalice ^[4]

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1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
2. U.S. Fish and Wildlife Service, Hadley, MA (United States)
3. National Marine Fisheries Service, NOAA, Silver Spring, MD (United States)
4. Low Impact Hydropower Institute, Boston, MA (United States)

Hydropower provides reliable and secure electricity and contributes significantly to the flexibility and stability of the US electricity grid. Hydropower dams generally are aquatic barriers and hazards to migratory fish in rivers. Fish passage facilities mitigate risks from hydropower to migratory fish, but information on these facilities is incomplete for the conterminous United States (CONUS). Here, we present the first CONUS-scale dataset of fish passage facilities at US hydropower developments in over 30 years. The existence of fish passage facilities (presence or absence) was specified for 1909 hydropower features, 390 of which had at least one facility. Most features had a single passage facility that provided passage in only one direction, with downstream being more common than upstream passage. Bypasses and ladders accounted for 60 % of the fish passage facility types. While we documented 659 fish passage facilities across CONUS, facilities were most common in the New England, Pacific Northwest, Mid-Atlantic, and Great Lakes regions. In general, fish passage facilities were more common at features that were closer to the ocean, at lower elevations, and at shorter dams, but not related to installed electrical generation capacity. Hydrologic sub-basins containing salmonids also contained the largest number of hydropower features, but the proportion of features with passage was generally higher in sub-basins containing multiple migratory taxa. This census provides valuable information on existing fish passage mitigation and is a benchmark to gauge progress toward a modernized hydropower fleet that provides affordable, reliable energy while protecting fishery resources and river ecosystems.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Water Power Technologies Office
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 2574467
• Journal Information: Journal of Environmental Management, Journal Name: Journal of Environmental Management Vol. 391; ISSN 0301-4797
• Publisher: Elsevier
• Country of Publication: United States
• Language: English