[thephyber]

Water rights is complicated in California.

The movie Chinatown was a "based on true events" kind of deal relating to California water rights when the state was going through growing pains in the post-WW1 boom.

The best I can figure, water rights (basically a contract which establishes how much water you have a right to use from which surface water sources) has to do with seniority. In 2015, the state regulators adjusted the coefficients in an effort to prevent starvation of downstream water rights[1].

I don't know how residential water districts compete with legacy water rights ownership, but I do know that residential water districts for the vast majority of the state's population get their water from just a small handful of inland reservoirs.

[1] http://www.nytimes.com/2015/06/13/us/california-announces-re...

[rconti]

This is the absolute best long read I've seen on the Colorado River and California water rights.

Interestingly, many forms of water conservation for agriculture actually have a negative impact. If farmers keep the same allocation but use it more efficiently, they're able to grow more, and there's less runoff so less groundwater recharge and less return to the river.

http://www.newyorker.com/magazine/2015/05/25/the-disappearin...