See? Even this cow has a better grasp of the English language than trump. "Cows_are_underrated" don't think I didn't see through your pro-bovine propaganda.
Basically, he's talking about rerouting the water coming from the Rockies that go into the Pacific and moving it into the drought ridden bits of California.... I think.
He's doing this with the phrasing you'd use to explain how the water cycle works to a toddler, mind you. So, if that's how he's trying to explain it to adults, that would suggest it's the only way he can understand it.