Does anyone know of a source of information on the velocity distribution in corrugated metal pipe or pipe arch culverts ? The concern is for fish passage. In a CMP or CMPA one would expect the velocity at the walls and along the bottom to be lower than the average velocity in the pipe. It would be very useful to know how much lower for any depth flow since fish cannot swim for very long if the velocity of flow is much above 5 ft/sec according to what I've read.