That's how much Ian Roth, the owner of the Seagull Inn, a bed-and-breakfast in this tourist town three hours north of San Francisco, spends on water every time a guest washes for five minutes under the shower nozzle.

Water is so scarce in Mendocino, an Instagram-ready collection of pastel Victorian homes on the edge of the Pacific, that restaurants have closed their restrooms to guests, pointing them instead to portable toilets on the sidewalk.

And the fire department has asked sheriff's deputies to keep an eye on the hydrants in response to a report of water theft.

"We've grown up in this first-world country thinking that water is a given," said Julian Lopez, the owner at Café Beaujolais, a restaurant packed with out-of-town diners in what is the height of the tourist season. "There's that fear in the back of all our minds there is going to be a time when we don't have water at all. And only the people with money would be able to afford the right to it."