.....arizona is not totally just dessert
flagstaff for instance has seasons...even snow
and theres pine top which that and flagstaff both have amazing forests *shrugs* just saying
technically putting rivers and such wouldn't change the climate of the desert...it would just cause for there to be water and dried up plants since plants that are not accommodated to the desert would die (except for mesquites...those are our invasive plants...and in this case plantoids)
I'm probably overthinking it and getting really technical which isn't necessary, but sometimes i can't help it...it just rolls out occasionally