A first step in recovering anadromous fish populations is determining how many barriers exist and where they are located. This information allows us to analyze fish passage barriers in relation to each other and in the context of the watershed where they are found. The California Passage Assessment Database (PAD) project was initiated as a statewide map-based inventory of known and potential barriers to anadromous fish in California. The PAD was developed in 2002 with guidance from the Forum, and the Forum, and in particular the Forum's Science & Data Committee, continues to guide the development and maintenance of the PAD.


The PAD is an ongoing project maintained through a cooperative interagency agreement that compiles barrier data from over 100 data sources, allows past and future barrier assessments to be standardized and stored in one place, and enables the analysis of cumulative effects of barriers in the context of overall watershed health. Read more about the PAD project or access the PAD data in an interactive map viewer.


The Database Online Review Tool allows users to review the PAD records in a map format and to provide feedback and editing comments back to the PAD team. Please take a moment to review barriers and potential fish passage sites in your area, and help update the PAD. ENTER THE PAD REVIEW TOOL HERE! Please use Firefox for best performance.

PAD Plan Implementation

In 2021, the Forum's Science & Data Committee contributed to the review and updating of the PAD Methodology & Data Standards (June 2021) and launched a major effort to review and update records in the PAD - an important tool used by restoration practitioners, decision-makers, funders, and fish passage professionals across the state to improve fish passage in California. The effectiveness of the PAD is dependent on how accurately its data depicts fish passage barriers in California (including information on their location, status, and other attributes), and representatives from the PAD and the Forum's member organizations are working collaboratively toimporve this information for the benefit of partners across the state. 

This comprehensive effort, also referred to as the "PAD Plan", is being implemented from south to north according to California Department Fish and Wildlife (CDFW) regions and is focused on non-Caltrans locations within priority (core and candidate) watersheds identified in NOAA Recovery Plans (Caltrans has implemented complementary efforts to update PAD records for barriers in their jurisdiction). A key component of the PAD plan in each CDFW region is the verification of barrier records by local experts. 

Building off lessons learned during the successful review of barriers in CDFW Region 5 (South Coast Region), on Tuesday, August 16th, the Forum hosted a webinar for practitioners with interest and/or knowledge of fish passage barriers in CDFW Region 4 (Central Region). This webinar introduced participants to the PAD Plan effort, the PAD, the Forum, and provided participants and opportunity to discuss current fish passage issues in the region.







If you are interested in contributing to the PAD Plan in CDFW Region 4, or other parts of the state, please contact Anne Elston (PAD Manager) or Neal Scheraga (PAD Data Management Specialist).


Additional Information

Inventory of Barriers to Fish Passage in Coastal Watersheds (13 MB)

Inventory of Barriers to Fish Passage in Coastal Watersheds - Appendices (7 MB)

Fish Passage Assessments