I am modeling a simple 300ft wide terrain about 1,5000 long (normal depth downstream BC) with a (Upstream hydro graph BC) 500 cfs design flow Tp 45 minutes (Everything else is pretty much default settings). However, my flow depth is 15 feet. I reduced the default “n” and got a depth of 10 feet.
The terrain is mostly flat with a shallow slope of about 1%.
Any idea what could make the water pond so high? Or any idea on a process to discover the issue will be greatly appreciated.