AESI (prime consultant) collaborated with ERM (sub-consultant) to perform 2D hydraulic modeling and fish habitat modeling on several streams in the Intermountain Region (Region 4) of the US Forest Service. The 2-dimensional hydraulic modeling computer program River2D was used to develop steady state hydraulic models and estimate reach level fish habitat characteristics for fry, juvenile, adult, and spawning life history stages of the following fish species: Chinook salmon, steelhead, bull trout, cutthroat trout, and brook trout. The team applied calibration and sensitivity analyses to fine tune the hydraulic model. Fish habitat modeling was completed to develop relationships between weighted usable area (WUA) and discharge. The team also explored the relationship between cover and habitat calculations through a macro developed in VBA.
The final product included a report detailing methodologies and results as well as all files produced during the project. AESI worked closely with the USFS to create the report, and the results are critical to future planning efforts for streams in Idaho and Montana. Procedures were carefully documented to ensure that the project will stand up to future scrutiny.