About HydroPASSAGE

There are more than 80,000 dams in the United States, over 2,000 of which are used to produce hydroelectric power. These structures can significantly impact millions of migratory fish, including salmon, American eels, and American shad.

Improving downstream passage of fish traveling through dams and other hydropower structures poses considerable environmental challenges for hydropower. The HydroPASSAGE project has been working to develop toolsets for the hydropower industry that can mitigate environmental impacts on fish passage. These toolsets are designed to provide information that will assist in design, operation, and evaluation of hydropower facilities that support fish habitats.

The HydroPASSAGE project is a research and development collaboration between engineers and biologists from the U.S. Department of Energy's Pacific Northwest and Oak Ridge National Laboratories that is finding solutions to improve downstream fish passage conditions through turbines and other hydropower structures. For more information on participating team members, please visit our Team page. 

Advancing hydropower for fish and industry 

The focus of HydroPASSAGE is to provide information and toolsets to increase fish survival through turbines and other hydropower structures across the United States and around the world. HydroPASSAGE toolsets enable us to:

  • Quantify the physical stressors at hydropower dams and assess effects on fish, such as injury and mortality, to support downstream passage evaluations of over 20 different fish species including American eel, Chinook salmon, and American shad.
  • Better understand how fish respond when exposed to hydraulic and physical stressors associated with turbines and other hydropower structures, such as spillways, sluiceways, and bypass systems. 
  • Support the development of new hydropower turbines, evaluate the performance of installed units, and understand the effects of changing operations on fish passage.


Tools and technologies for next-generation hydropower

The HydroPASSAGE toolsets include:



The Biological Performance Assessment (BioPA) tool relates computational models of hydraulic conditions to known effects to fish to inform the design and operation of hydropower turbines.



The Hydropower Biological Evaluation Toolset (HBET) analyzes hydraulic conditions and offers measurable estimates of the physical stressors fish may experience at hydropower dams.

Sensor Fish prepared for deployment

Sensor Fish

The Sensor Fish is a small, cylindrical tube that contains a variety of sensors. This can be used on-site to measure the hydraulic conditions that fish might experience during passage.

Research Priorities 

Research priorities for the HydroPASSAGE project are described below.

1. Improving the biological performance of hydropower turbines and understanding fish resiliency to turbine passage.

Experiments conducted for this project provide important biological response information, such as impacts to fish from exposure to forces that may be encountered in the turbine environment. Fish species prioritized for investigation were those that possess traits that increase their likelihood of going through turbines (e.g., migratory habits), sensitivity of response to turbine stressors (e.g., scale type for fluid shear, swim bladder type for rapid decompression), regulatory or conservation concern, or presence in river systems where new hydropower construction is scheduled.

Future HydroPASSAGE research in this area will:

  • Support data collection efforts that evaluate downstream fish passage baseline conditions and provide tools to suggest and validate improvements.
  • Summarize and consolidate information on turbine impacts to fish.

2. Continuing to apply tools and technologies for next-generation hydropower: 

The HydroPASSAGE project has focused on the development of toolsets and information that can be used to mitigate the impacts of hydropower turbines.

Future HydroPASSAGE activities in this area will:

  • Seek industry partners to use, demonstrate, and increase the utility of HydroPASSAGE tools.
  • Support decision-making within the hydropower community by clarifying design requirements, constraints, and methods to evaluate and improve fish passage.
  • Establish lessons learned and best practices to accelerate technology transfer of HydroPASSAGE toolsets, information, and data.
  • Understand end-user needs and quantify value of HydroPASSAGE applications through the transfer of the HydroPASSAGE toolsets and technologies to the hydropower community through industry collaborations.
  • Identify near-term market applications of HydroPASSAGE toolsets that support hydropower modernization and sustainability efforts and to enable high rates of fish survival through hydropower turbines and facilities.