ABSTRACT
Box culverts are generally considered more effective for fish passage than circular pipes. While there are a broad range of culvert designs resulting in a wide diversity in turbulent flow patterns, there are still ongoing discussions regarding how the flow turbulence characteristics might interplay with fish passage and fish behavior. Simply, the fish—turbulence interactions are extremely complicated, and naive “turbulence metrics cannot explain all the swimming path lines or behavior”. A laboratory model is designed to provide reliable predictions of the full-scale hydraulic structure. Physical modeling is a classical tool in hydraulic engineering to analyze complex flow. Fish kinematics, based upon high-speed video movies deliver seminal insights into fish behavior and trajectories, fish speed and acceleration, tailbeat frequencies, and fish swimming energetics. The fish speed auto-correlation time scale gives some information on the reaction time of the fish, while the fluid velocity auto-correlation time scale is a rough measure of the longest connection in the turbulent behavior.
