I'm going to be a bit pedantic because I do think it's important that folks get a full understanding of what the water situation in California is that doesn't sound cherry-picked or narrative driven.

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

80% of human consumption is by agriculture and most of that agriculture is not satiating the needs of Californians. It's also important to note that farms are doing significant work on this:

> Higher-revenue perennial crops—nuts, grapes, and other fruit—have increased as a share of irrigated acreage (from 16% in 1980 to 33% in 2015 statewide, and from 21% to 45% in the southern Central Valley). This shift, plus rising crop yields, has increased the economic return on water used for agriculture. Farm production generated 38% more gross state product in 2015 than in 1980, even though farm water use was about 14% lower.

The rest of the economy is outpacing these efficiencies though, so it pales agricultures value to the GDP year over year.

Urban water usage is also falling:

> The San Francisco Bay and South Coast regions account for most urban water use in California. Both rely heavily on water imported from other parts of the state. Total urban water use has been falling even as the population grows. Even before the latest drought, per capita water use had declined significantly—from 231 gallons per day in 1990 to 180 gallons per day in 2010—reflecting substantial efforts to reduce water use through pricing incentives and mandatory installation of water-saving technologies like low-flow toilets and shower heads. In 2015, per capita use fell to 146 gallons per day in response to drought-related conservation requirements. Much of the recent savings came from reducing landscape watering, which makes up roughly half of all urban water use. Per capita use has since rebounded slightly, but a new state law will require further long-term reductions.

Big takeaway here, large urban centers are not in our best interest.

Environment use is split into four categories:

- Water in rivers protected as “wild and scenic” under federal and state laws

- Water required for maintaining habitat within streams

- Water that supports wetlands within wildlife preserves

- Water needed to maintain water quality for agricultural and urban use

> Half of California’s environmental water use occurs in rivers along the state’s north coast. These waters are largely isolated from major agricultural and urban areas, and their wild and scenic status protects them from significant future development. In dry years, the share of water that goes to the environment decreases dramatically as flows diminish in rivers and streams. At the height of the 2012‒16 drought, the state also reduced water allocations for the environment to reserve some supplies for farms and cities.

I think environment needs to be split out into its own categories, one is very farm adjacent, two have to do with maintaining habitats that (our own) interactions have devastated or made dependent on artificial means, and the last is basically "untapped" water.

Fixing water in California isn't going to be as simple as sweeping changes in agriculture, though that is needed as well. It also means dismantling dense urban centers and making them more sustainable and establishing criteria for when we support a habitat artificially and for how long.