My pond is going to be excavated and not have a regular dam, just an overflow drain and emergency spillway. I’m going to repurpose the current drain in the area that’s currently used for downspout and sump pump discharge and runs down to a culvert. The downspout and sump will be rerouted into the pond. My concern is the elevation of everything, especially since the line for sump and pond drain are at basically the same depth. How do I have the pond pipe drain and emergency spillway drain without back flowing into the sump/downspout line?
I had considered having the sump at or very near the water surface with a back lower preventer but wasn’t sure that would consistently drain the pipes and/or be safe in flood times if the emergency spillway was in use.
Never say never but the pond will be about 1/4 acre and will only be fed through runoff (about 2 acres of watershed) and the sump/downspout so I don’t expect the emergency drain drain would be used much at all.