Agriculture uses 90% of the water in California growing cotton, alfalfa and almonds, which are all very water intensive, Humans watering their lawn, drinking water and bathing, use a fraction.

Note: The way they divide up water usage. They have a third category, listed As environment, but that’s misleading because the people who have the water rights can always use a lot more water at their discretion at any time. where as the common citizen cannot.

https://en.wikipedia.org/wiki/Water_in_California

https://www.ppic.org/publication/water-use-in-california/