Design of a Fish Barrier for San Bernardino NWR

A feasibility study and fish barrier design is being conducted for the U.S. Fish and Wildlife Service in support of the San Bernardino National Wildlife Refuge, located east of Douglas, Arizona.    The barrier has three goals: The first and primary goal is to prevent the upstream migration of non-native and invasive fish species from entering the refuge which currently houses threatened and endangered fish species.  The second goal is to design the structure to support the accumulation of sedimentation upstream, therefore raising the bed elevation to support a long term re-establishment of the historic cienega features.  The third goal is account for native fish species travel downstream during storm events and minimize the potential for fish mortality within the region of the proposed fish barrier.

 This presentation will include site photography, a review of the feasibility assessment, a review the design considerations, and show the resulting design for the fish barrier.  Design elements that will be discussed include the species of invasive fish, their swimming and burst rates, and the fish jumping heights which govern the barriers crest elevations. Additional engineering elements to be discussed include the geotechnical characteristics of the site and structural considerations for the barriers design life.