Man-made barriers to fish passage include road/stream intersections, pipeline or other infrastructure crossings, erosion control/flood control structures (rip-rap, concrete channels, etc), and dams which block or delay the migration of salmonids upstream. These barriers impact both adult and juvenile fish by preventing full use of available habitat or altering habitat, hydraulic conditions. Road/stream crossings are extremely numerous and often cross multiple road ownerships within a watershed. Passage impediments and delay in migration affect adult and juvenile fish, preventing the useful use of available habitat, as well as inflicting injury or death of fish attempting to migrate upstream. A comprehensive California fish passage program is vital towards identifying, prioritizing, and treating migration barriers so that unimpeded migration of California’s salmonid populations is achieved. Through coordinating

Prior to replacement, the culvert shown above, located on South Fork Anker Creek in Humboldt County, not only served as a complete barrier to all life stages of salmonids, but was also extremely undersized.

resources and authorities and creating the Fish Passage Forum, a comprehensive program will be achieved. The Five Counties Program has aggressively targeted Migration Barrier Removal on County Roads as one of it's top priorities since 1998. Through the Five Counties Migration Barrier Inventory, consulting biologist Ross Taylor identified stream crossings on County Roads that prevent the upstream migration of salmonid species. These barriers were prioritized in our Migration Barrier Ranking Matrix and the implementation stage of the program has been well underway for several years. As our Migration Barrier Removal Progress Matrix indicates, the program has completed 50 barrier removal projects on County Roads, restoring access to over 124 miles of habitat for coho and Chinook salmon as well as for steelhead and cutthroat trout. Nine additional projects are slated for construction in 2008 -2009. For information on completed barrier projects in
individual counties, click on the County links above.

An inventory of the Russian River migration barriers was also completed by Ross Taylor & Associates. Download the invenotry (PDF file): Russian River Migration Barrier Inventory. Margaret Lang completed a barrier inventory of Caltrans District 1 crossing structures. Download the inventory (PDF) file: Caltrans District 1 Pilot Fish Passage Assessment Study: Volume 1 - Overall Results.