did not meant to send that yet....

as I was saying about calculating runoff area. I have some questions

Does the surface area of the water body count in the runoff formula? ie does a 1:1 ratio imply there is no runoff other than the surface itself or does it imply a runoff equivalent to the surface area outside of the water body? (sorry if that is not as clear as it could be)

Does the land need to be a certain slope or can a mostly flat plateau area or hilltop count also in the consideration?

My initial calc of 3:1 is based off my visual estimation of where the slope starts. After going back and using better tools it seems that maybe I could count much more that has a subtle and gradual slope.