It's really not. https://droughtmonitor.unl.edu/

California is not in any drought right now and our reservoirs last 10 years in the absolute worst case. Most of our water goes into the ocean.

I have no dog in the race in terms of what trees there are but if you take them down it'll be invasive South American pepper trees or mustard grass. As long as it's used and sequestering carbon it's all gravy.