Water like oil

Crumbling levee system protects Missouri town: CNN California suffers at least 700 wild fires from a weekend lightning storm, and because of the drought this is going to be a rough fire season. CNN

With all our focus on oil, water is just as important. Why cant we build a dam and water pipeline system so that when the Mississippi rises like this, we send the water west.

What about desalinating sea water?

You think that with all the smart people out there, someone hasn't thought about this?