We live by a huge river Julian and up above a bit, close to its outlet and the ocean. Therefore we have no trouble as the house is built on solid mountain where drainage is very good. On the other hand, up stream they have problems, even newer establishments whose calculations have been quite diasterous! Where other rivers, lakes and valleys are flooded. I'll show you all some samples after I come back to the flatlands from climbing heights of 2000 meters and so.
Now I'm halfway down and I assume it shall take som days to get back down, as branches, brushes, trees and certain boulders has to be removed by my bare hands and my axe from my scouting days!
Appreciate your concern!