This New York Times story is worth a read. To me it hints at a possible solution to a lot of the West's water problems.
The story explains why one family in California's San Joaquin Valley has decided to lease their ranch to a solar power company instead of continuing the uphill battle of growing almonds and pistachios.
Irrigation and drainage problems have left some soil too salty to farm, and environmental conflicts over providing water for salmon have reduced water deliveries for agriculture. Meanwhile, the Sacramento River salmon runs are still in pretty bad shape and probably need even more water if they're going to recover.
Here's a good bit from the NYT story:
In other parts of California, the prospect of covering square miles of farmland with solar panels has stirred outrage among some rural residents. But Mr. Shannon and Westlands officials don’t expect any significant opposition in the San Joaquin Valley.
The reason: if farmers such convert their land to solar farms, their water allocations will be redistributed to their neighbors.
“Our family had to get over the broken heart of losing this ranch,” said Mr. Shannon, who plans to continue farming on land his family owns on the east side of the San Joaquin Valley. “But if we can shift the water supply off, say, 15,000 acres, that’s a win-win for the growers left behind.”