I'm with you on the water usage. I think it is just sheer numbers. The City of Phoenix has this optimistic page about how per capita use is down, but they obfuscate the total usage by saying there are 1.5 million people in Phoenix. https://www.phoenix.gov/waterservices/resourcesconservation/yourwater/historicaluse Yes, in the city limits, but we are surrounded by a lot of other little cities. There are 4 million people just in Maricopa County. You could take the City's per capita use and multiply that by about 4 (for the other counties drawing mainly from the Colorado) and have a better idea of the actual use. Agricultural use is mostly irrigation from the CAP. Their excess is dumped at the end of the line in the desert, where it is building up an aquifer, but it's coming from the river.

I also believe the less snowfall part, because we have had fewer storms too. It really is dry all over, just when everyone decided to move to a warm climate, and it isn't the result of a few planes spraying anything, no matter how much people want to believe in the butterfly effect. This covers hundreds of thousands of square miles. It might be related to a lot of commercial jets putting out their stuff though. It seems a tad cleaner and cooler now that there are noticeably fewer flights. It might also be related to the fact that these big cities like Phoenix and Las Vegas are heat islands, an effect no one knew about when the cities were being developed nor did they plan ways to reduce it. The result is that storms tend to wither and go around the populated areas and the cities get hotter and the residents want more swimming pools and iced tea. We have had two thunderstorms in the last two weeks that were the way I remember them being from 20 years or more ago. If we had them weekly like then it wouldn't be necessary to water the grass, which is mostly Bermuda grass and will survive anything.