Diverting the Colorado or the the Green (since the Co. failed) to feed urban growth is a crime. But one that has gone on for decades. Obviously the people in the parched desert of W. Co. or Utah, or S. Wyoming don't need it.And since the Colorado does not reach it's mouth for decades, diverting any of it's tributaries must be good for the river...
Read Cadillac Desert to find out how water follows money. China Town the movie also exposes the ruthlessness of the power brokers in Hollywood fashion. Reality was worse.
That is why Cat is more fun than the Grand tho shorter and not as spectacular it is still a somewhat wild river.