CA DWR “Be Well Prepared”  Program for Californians Dependent on Groundwater

(Press Release, California Department of Water Resources; May 17, 2023)

https://water.ca.gov/News/News-Releases/2023/May-2023/DWR-Launches-Be-Well-Prepared-Program-to-Ensure-Safe-and-Reliable-Drinking-Water-for-Households?utm_medium=email&utm_source=govdelivery

Also…

Identifying areas of degrading and improving groundwater quality conditions in the State of California, USA, 1974 – 2014 (JURGENS et al., 2020)

https://link.springer.com/article/10.1007/s10661-020-8180-y