Barriers preventing the upstream movement of nonnative salmonids are a keystone practice in the conservation of southwestern native trout. Arizona Game and Fish Department manage dozens of barriers throughout the state. However, monitoring showed that many of the barriers were ineffective. We were asked to develop an assessment protocol, assess problem barriers for fish passage, propose, design and oversee the construction of repairs and additions and design new barriers as needed. NCD Engineering provided hydraulic, structural and geomorphic stability assessments for over twenty barriers. Concept designs were developed for approval by AGFD and the USFS. Designs had to be implemented in remote areas only accessible by foot, pack animal or helicopter. Final designs and construction drawings have been completed and 6 projects have been implemented. Several large barrier designs are currently underway and assessments are ongoing as a result of severe wildfire and consequent changes in hydrology.
NCD Engineering was the lead design consultant for this project.
We ultimately developed design criteria for successful fish barriers to help achieve conservation goals and the delisting of endangered southwestern salmonids.