No, start with modifying the Colorado River Compact and other underlying agreements to allow more upstream retention than is currently allotted.
Could you save on pumping energy by sending the water to underground aquifers rather than the surface?
Just install some additional solar powered pumps along the way
The amount of energy needed to pump enough water for ag uphill is insane. Well beyond "just" throwing some solar panels out there. If it was that easy we'd pump Mississippi water into west Texas (which there was a plan to do in the 60s with nuke plants, but I cannot find the name right now).
i left off the /s as to me anytime someone starts a comment off with "just ____" is usually a farcical idea. like just remove the salt from water and boom, done.
Hah! It can be a very HN comment to "just" something especially around physical engineering.