For structures with natural or embedded bottoms, should outlet grade be considered "at grade"? We had a couple of structures that seemed to have a "cascade" at the outlet, however, it appears to have been a natural condition of the stream bed.
Tried to capture in the attached photo.
Thanks for providing a photo with your question- very helpful. That would be considered "at grade". Those large boulders/cobbles are part of a riffle at the outlet. In these higher gradient, boulder- dominated mountain streams your team is working in, I think your team will come across this quite often.