Assessing Fish Passage

Photo: Erika Bailey, TNC
The objective of most road-stream crossing assessments is primarily to identify stream crossings that are problematic from a fish passage perspective. Some assessments can help identify structures that are vulnerable to flooding or failure; these are described in assessing vulnerability section of the toolkit. Field assessments are not decision-making tools; they are means for collecting initial information about conditions at road-stream crossing sites.

Various regional field assessment protocols have been developed and revised over the years. Using an existing regional protocol has many advantages, including access to regional databases that are already created and maintained, contributing to larger scale prioritization, and saving time and resources.

If the forms and questions do not fit your needs exactly, we recommend that you follow the relevant regional protocol and add a separate data sheet to answer additional questions of importance. This will allow your data to still fit into one of the existing regional databases.

Regional Stream Crossing Assessment Protocols

Northeastern U.S.:  The North Atlantic Aquatic Connectivity Collaborative (NAACC) is a network of individuals from universities, conservation organizations, and state and federal natural resource and transportation departments focused on improving aquatic connectivity across a thirteen-state region, from Maine to West Virginia. The NAACC has developed common protocols and training for assessing road-stream crossings for aquatic organism passage and developed a regional database to store and organize this field data.

Great Lakes Region: The road-stream crossing survey protocol for the Great Lakes region is a screening-level assessment tool developed by state and federal agencies in Wisconsin and Michigan and several conservation organizations. Information collected at each site provides an estimate of passability by fish, and an estimate of the cost of replacing the existing structure with a fully passable structure.

State and Agency-Specific Assessment Protocols

California Fish Passage Forum:  

Oregon Department of Fish and Wildlife:

Washington Department of Fish and Wildlife:

Alaska Department of Fish and Game:

U.S. Forest Service:

  • National Inventory and Assessment Procedure for Identifying Barriers to Aquatic Organism Passage at Road-Stream Crossings
  • Road-Stream Crossings  
  • FishXing software tool

Additional Resources

Scientific Basis of Road-Stream Crossing Assessments in the Ashuelot River Watershed