Session A4 - On the Cutting-Edge: Optimizing Fish Passage Mitigation Decisions in California Watersheds

The California Fish Passage Forum is a consortium of state and federal agencies and NGOs whose mandate is to improve fish passage in anadromous waters. The Forum is now embarking on the implementation of a state wide methodology for prioritizing the removal of artificial fish passage barriers. The methodology, which employs highly sophisticated optimization modeling and solution techniques, represents a radical improvement over standard, scoring-and-ranking type procedures commonly used for prioritizing barriers in the US, Canada and other parts of the world. Optimization based methods provide a systematic and objective means of targeting barrier mitigation decisions which maximize restoration gains given available resources. The optimization methodology being implemented by the Forum integrates information on barrier location, passability and cost together with river habitat and quality data for multiple target species in order to identify cost-efficient passage improvement strategies. Critically, the spatial structure of barriers and the interactive effects of passage improvement on longitudinal connectivity are explicitly taken into consideration. Another key feature of the Forum\u27s prioritization methodology is its ease of use. A user-friendly Windows based program, replete with a graphical user interface, has been implemented, allowing Forum members to quickly and easily generate optimized solutions as well as perform basic what-if analyses in terms of running different budget scenarios and or varying the relative weightings placed on individual target species