The purpose of this project is to evaluate how the size of hydraulic structures used at crossings over waterways relates to the initial investment, operations and maintenance effort, and impacts to fish passage and stream function.  This effort will better inform future road-stream crossing designs with the goal of achieving cost-effective designs that provide proper fish and other aquatic organism passage, stream function and resilience to changing climates without excessive initial investment.

This research will attempt to answer the following question: Do larger crossings that better accommodate stream function than smaller crossings, such as those sized less than the bankfull width of a stream, require less operations and maintenance effort?  The research approach will combine field studies at culvert crossing locations in a cold region with analysis of relationships between the size of culverts, stream characteristics, crossing function, and operations/maintenance effort.