What this basically means is the end of most irrigated farming west of the Continental Divide until further notice. Farmers will scream but they're outnumbered by city dwellers 50 to one.
The way water rights have been structured, there is a disincentive to save water; if you don't use all of your allotted rights, you can lose them! Naturally, that has put a real crimp in efforts to promote water conservation. Farmers use 80% of the water drawn from the Colorado River (similar to most places), so they'll be the ones asked- told- to cut back.
There are some amazing water conservation technologies out there, from drip irrigation to semipermeable mulching systems, etc. Some way must be found to encourage the adoption of these approaches.
This is already the worst drought in 1200 years. It's not getting better so adaptation or death is the choice.