i have a well ...and with the property being so close to the lake i dont see it ever running out .....with the bills that are in congress the gov want to vote in all the rites to everybodys water supply as an attemp to steel private water sypply so your ideal is not a bad ideal at all especaly since the building has a natural fall with the grade that would make collecting water a snap like it was design for it ......thanks rhino i hadnt thought about how easy this could be done and the fact that gravity could power the system to most other parts of the dwellings on the property......it would be a great supply of water in times of no power....