Re: Biggest problem.
But they do NOT have the water.
I owned an 80 acre parcel out that way. It included the last twelve years of a 99 year water lease. For seven years I grew pumpkins and other squash on it. It was very profitable. I spent most of those 7 years trying to figure out how to extend the water lease, but the State of California was adamant: NO! Most of the locals were in the same boat. Basically, it's scrub land that is good for not much more than grazing a few cattle on. You don't need as much water for cattle as you might think ... consider that most of the BLM land in California's southern deserts is cattle grazing land.
So I sold the place to a friend who had been helping me in the squash business. He knew that he'd be out of water in 5 years, but figured he'd be able to pocket enough loot to purchase land on one of the islands in the Delta to keep the farm going. He was successful, and sold the original property to a developer[0] who didn't care about the lack of water. It has been sitting empty ever since (25+ years now).
To see what the place looks like, try this map:
https://www.google.com/maps/@38.2135488,-121.8026745,11278m
It's the bit in the middle, north of Hwy 12. Not the extreme lack of much of anything. No row crops, no signs of major grazing, no signs of harvesting, etc. That's what no water gets you.
[0] No, not these yahoos. Although that guy may have unloaded the parcel on them. I can't be arsed to find out.