There is a dam along one side of the pond, and fairly steep. At the edge of the dam is the spillway, also with lowering terrain for good outflow.
I think I need to look at the 4" thinwall pvc idea. My water pump only has about a 1 gallon gas tank. If it would need 24 hours to drop two inches-- yikes! No sleep ha ha.
The valve is part of an irrigation system. It was damaged but never repaired. Next spring, when I want to pressurize the irrigation (gravity flow) this broken pipe/valve will be compromising that. At a minimum I just need to cap the pipe and do a full repair in fall when water levels are down. I'm also considering digging along the shore to find it and cap it ... out of the water. Of course, there are no plans whatsoever .... so I'd be having to guess where to dig.
