I don't mention it because it's not true. The idea that if a river originates in one state, then that state owns all the water from the river is not how ownersh

I don't mention it because it's not true. The idea that if a river originates in one state, then that state owns all the water from the river is not how ownership of river water works. And in America, rivers often form the border of states, so there are always competing claims about which state gets which percentage of the river. These are generally settled through treaties and agreements among states, and those agreements were made also for the Colorado river. Arizona is only taking its share of the water as per the treaty, not someone else's share.