But corporate agriculture is free to plant all the water-gulping nut orchards it desires, even in a semi-desert.
This is the essence of the governor's new long-term drought policy that he announced Monday.
Brown intends to make permanent some urban water conservation rules that had been temporary. He also plans to give communities more flexibility to decide how much water they should save, depending on local conditions. But it's basically hands off agriculture.
The governor issued an executive order declaring that the state must "move beyond temporary emergency drought measures and adopt permanent changes to use water more wisely and prepare for more frequent and persistent periods of limited water supply."
He directed the State Water Resources Control Board to, among other things, "eliminate water waste" in urban areas. He specifically mentioned hosing off sidewalks and driveways, washing cars without a shut-off nozzle, sprinkling lawns in a way that causes runoff and irrigating grass on public street medians.
Well, OK. Everyone needs to do their part.
But let's not forget: Residential lawns soak up only about 5% of developed water in California. All residential outdoor use — including pools, shrubs, trees — amounts to less than 7%. Total urban use — showers, washers, business landscaping, golf courses, ball fields — account for just 20% of human water consumption.
Agriculture slurps up 80%, much of it in the semiarid San Joaquin Valley, where growers increasingly have been planting thirsty nut orchards, mainly for profitable export overseas.
But while agriculture devours 80% of the developed water, it accounts for only 2% of the state's gross product, according to the nonpartisan Public Policy Institute of California.
Last year, as Californians dealt with the fourth year of drought, growers planted an additional 60,000 acres of almonds, mostly in the San Joaquin Valley, according to state agriculture officials.
That was a 6% increase in almond acreage over the previous year, bringing the total to 1.1 million acres. That's nearly double the number of almond orchards that existed 12 years ago.
Unlike carrot, tomato and other vegetable plants, nut and fruit trees cannot be temporarily fallowed during dry years.
So when government reduces water deliveries through the giant aqueducts, farmers feel compelled to drill deeper wells, further draining aquifers. The result is that land in much of the San Joaquin Valley has been sinking, damaging roads and canals and drying up water supplies for hardscrabble local communities.
The state lists 21 "critically overdrafted" water basins, covering practically the entire San Joaquin Valley. The Paso Robles area and Oxnard also are on the list.
In 2014, Brown signed landmark groundwater management legislation — California's first. But it basically punted the chore of refereeing water use to local agencies. And the rules won't fully take effect for another generation.
Back to almonds. Not all of them are equally thirsty. It depends on their location.
In the wetter Sacramento Valley — the northern part of the Central Valley — one acre of these nuts requires 2.4 acre-feet of irrigation water annually, according to the UC Davis Center for Watershed Sciences. In most of the San Joaquin Valley, they need 3.4 acre-feet. But in the lower valley, they gobble up 4 acre-feet.
Roughly 85% are in the parched San Joaquin. Do the math: Those additional 60,000 acres of almonds require more than 200,000 acre-feet of water per year, enough for 400,000 households.
Making this really simple, one gallon of water is generally needed to grow one almond.
Yes, the water produces food, but most of it isn't for us. It provides snacks for other countries, primarily in Asia.
"I believe farmers should grow whatever they want," Brown told me last year.
Never mind that government regulates practically all other land use. A property owner can't just willy-nilly build an apartment house, develop a mall or carve out a dump.
Brown did, however, pester farmers a little in his executive order.
Irrigation districts serving at least 25,000 acres currently are required to develop drought management plans and monitor groundwater levels, reporting the numbers to Sacramento. The governor's new edict lowers the acreage threshold to 10,000, covering an additional 1 million acres of farmland.
But there's no enforcement of the current regulations.
"There should be," says Mark Cowin, director of the state Department of Water Resources. He says enforcement legislation will be proposed by next year.
"What we're trying to do is see how efficiently agriculture uses water," Cowin says. "We're staying away from mandating land use and types of agriculture."
But agriculture is going to be constrained anyway eventually — by nature and by groundwater regulations — predicts one expert.
"There's not enough water," says Jay Lund, director of the UC Davis watershed center. "It's inevitable."
Lund says less water will be exported south from the deteriorating Sacramento-San Joaquin River Delta. Groundwater is being depleted and contaminated. Seas will rise because of climate change, pushing more saltwater inland. Less snow will fall in the Sierra. San Joaquin Valley soil will become more toxic because of irrigation runoff and imported salty water. And urbanization will eat up cropland.
He says up to 2 million of the San Joaquin Valley's 5 million irrigated acres will need to be fallowed.
"That looks right to me," Cowin says.
Not hosing down your driveway won't amount to a hill of beans.
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