True story: I am an engineer involved in the replacement of a 70 year old bridge. It goes over railroad tracks. The railroad has not kept the ditches on each side of their tracks cleaned. One silted in and left water that is 12” to 18” wide, zero to 3” deep, and about 200’ to 250’ long. There is nothing living in it. The water is there after a rain until it soaks into the ground.
The Feds ruled that the ditch is a federally protected wetland. We have to surround it with fencing during construction to keep it from being “damaged”. We have to produce before and after photos, dimensions, and a report showing that we have not damaged it when the construction is done.