"dropping underground water levels"
I'm positive you know more about this subject than I do given your area and the farmland. I had a hydrologist tell me once that the only true way they know how much water is being lost from aquifers is by measures taken from satellites. The problem is that measures how much water is being lost not how much there is left. That they can't determine.
Water and the entire central valley is a subject that has been at the forefront of California since statehood and obviously will continue with greater emergency in the near future.
