[kolanos]

We don't need to rely on hunches.

> In an average year, about 39% of California's water consumption, or 34.1 million acre-feet (42.1 km3), is used for agricultural purposes. Of that total, 11%, or 8.9 million acre-feet (11.0 km3) is not consumed by the farms for crop production but is instead recycled and reused by other water users, including environmental use, urban use, and agricultural use, yielding net water consumption for food and fiber production equal to 28% of California's water consumption, or 25.2 million acre-feet (31.1 km3). [0]

The 80% figure is false.

> In a normal year the CVP delivers about 7 million acre-feet of water for agricultural, urban, and wildlife use. [1]

Suffice to say the CVP supplies a significant portion of California's water. It is the largest such project in the country.

[0]: https://en.wikipedia.org/wiki/Water_in_California#Agricultur... [1]: https://www.watereducation.org/aquapedia/central-valley-proj...

[diggernet]

From your Wikipedia link:

> Water use in California is divided into approximately 51% for environmental uses, 39% agricultural use and 11% urban uses, though that varies considerably between regions and between wet and dry years. Solely relying on these statewide volumes is controversial because they don't consider the fact that most of the volume of water used for environmental purposes includes flows down Wild and Scenic Rivers in the North Coast where there is no practical way to recover it for either agricultural or urban use because it lacks many connections to the statewide water supply system. It also doesn't factor in the amount of water required to keep salty water from the Pacific Ocean from intruding into the Delta beyond a certain small concentration.

If we set aside the 51% of California's water that isn't actually used by people, that 39% of total water becomes 79.6% of water used. So, yeah, 80% of usage.

[kolanos]

> Solely relying on these statewide volumes is controversial because they don't consider the fact that most of the volume of water used for environmental purposes includes flows down Wild and Scenic Rivers in the North Coast where there is no practical way to recover it for either agricultural or urban use because it lacks many connections to the statewide water supply system. It also doesn't factor in the amount of water required to keep salty water from the Pacific Ocean from intruding into the Delta beyond a certain small concentration.

These are solvable problems, so excluding that water from the ~40 million acre feet of water California uses every year seems like a convenient way to balloon the other uses. Plus as cited earlier, of the 39% of water use attributed to agriculture, 28% of it actually has multiple uses in addition to agriculture and is recycled (the 11% figure). So only 28% of the total is actually exclusively used for agriculture.