It’s outlandish, urban critics note, for big farm units to be growing alfalfa — which consumes about 20 percent of the state’s irrigation water — or raising cattle, in a place with a third of the rainfall of other states. And by exporting that alfalfa and other thirsty crops overseas, the state is essentially shipping its precious water to China.

Still, casting California farmers — who produce about half of the nation’s fruits, nuts and vegetables — as crony capitalist water gluttons may not be entirely fair. Yes, the water is subsidized, through taxpayer-funded dams, canals and pumping systems. But that water, in some cases, ends up as habitat for birds and wildlife. As it drains away, it can recharge badly depleted underground aquifers. Farmers have already let more than 400,000 acres go fallow and took a $2 billion hit last year. They may add 600,000 acres to that total this year. Almonds, after all, are a healthy food source.

The new morality tale becomes further muddled when you consider that San Francisco, praised for its penurious water ways, gets its life-supporting liquid from the Hetch Hetchy dam, in Yosemite. Many people, dating from the sainted John Muir, believe that flooding that mountain valley was one of the bigger crimes against nature in California history.

And not every city is Spartan with its water. On any given day you can find, as I did in a new housing development in the foothills east of Sacramento, water running down the street — at a flow rate that looked bigger than that coming from the anemic Merced River. It was pouring onto a grass median strip, and then spilling over, in a development called the Estates at Blackstone.

Or consider that wealthy communities — say, Portola Valley, woodsy home to many an environmentally conscious tech multimillionaire — use far more water per capita than do the poor of Compton, in the Los Angeles area. When cost is no object, there is very little incentive to cut back.

But there is no getting around the fact that agriculture, for all its water needs, still produces barely 2 percent of the state’s gross product, and employs only about 3 percent of its workers.

Fair or not, it seems incongruous that farmers in the San Joaquin Valley are still planting new almond trees — they’ve nearly doubled the crop since 2005 — while people in the cities kill their lawns and dash in and out of low-flow showers.