Thanks for the reply! Good point about the spillway. What is the ideal slope for an emergency spillway? In the "worst but not best case scenario" of having a poor ribbon test, but at least not hitting bedrock.. is a secure dam still feasible? While the obvious answer would be a pond further down the hill, the "open field" is livestock pasture and the further up I can build a pond, the better gravity feed potential I have for irrigation use, etc. Ideally, I would also like to construct a second pond on the east property line, where there is a gully forming in that valley from a spring that is flowing down the channel and causing erosion. This second dam would have to stretch across the property line onto the neighbor's land, but it might one day be possible. Assuming I could get these two ponds to a fairly decent size, I would then want to wrap thin, long ponds around the hillside on contour with interconnecting swales and terraces for growing various crops and trees. That is my fantasy, at least.
