This urbane city, which prides itself on its good life-style and patrician ways, is about to become the home of the recycled bathwater, the unwashed executive and, horror of all horrors, the unflushed toilet.

Capitulating at last to the necessities of water conservation in the midst of the West's worst drought on record, officials today prepared the final touches on the first mandatory water-rationing plan imposed on a major U.S. city.

The plan will place a 25 per cent cut in water use on all of San Francisco's 670,000 residents. The same rules will apply to hotels, most offices and all industries except those such as car washes or breweries that can demonstrate that water is essential to their operation. Industries in this category will lose 10 per cent of their water supply.

The regulations require that all new construction be equipped with water-saving devices and ban the watering of cemeteries and golf courses. Residents won't be allowed to wash their cars or their sidewalks with hoses and no outside watering that allows runoffs down the sewer or gutter will be allowed.

"We need a 25 per cent cut in the city's water use right now or there won't be any water coming out of the faucet by next January," said Kenneth Boyd, general manager of the San Francisco Water Department.

The city has been the last holdout in the general water rationing in effect throughout the San Francisco Bay area. Some suburbs, such as those in Marin County north of San Francisco, have cut water use to as low as 42 gallons a day per person, a more than 50 per cent reduction.

Despite the cutbacks here, which are scheduled to begin within the week as the water department mails out water quotas to its customers, there was a certain before-the-siege jauntiness among some city officials today. "The Scotch-and-water drinkers will just have to shift to drinking it on-the-rocks," said an aide to San Francisco Mayor George Moscone.

The mayor, on his way from City Hall to a waterless luncheon engagement, said the water restrictions might not harm the city's image. "It's really a state of mind we're after," he said. "The real essentials to the lifestyle San Francisco projects aren't going to change."

Nevertheless, signs of the drought's effects are in evidence everywhere here. Arriving travelers at San Francisco International Airport are met by recorded announcements urging them to save water. Car-rental agents warn that there may be a little grime on their vehicles because they no longer wash them.

Virtually all the city's hotels have small signs in their rooms urging guests not to overuse the toilet or the shower. Some motels have stopped changing linen on a daily basis in order to conserve water.

At the Mark Hopkins Hotel on Nob Hill, where guests pay up to $265 a day for a suite, small cards were being distributed suggesting that tourists not flush trash down the toilets at seven gallons a flush.

"We're not using hoses to water our terrace greenery and the garage isn't washing cars anymore," said Lew Malone, food and beverage manager for the 418-room hotel.

Guests don't get water with their meals unless they ask for it and the hotel laundry recently cut the number of rinses in its daily wash load from seven to three. In the kitchen, chefs no longer soak the blanched asparagus under running water the way they used to, Malone said.

"It's a matter of survival and good citizenship," he said. "You can't argue with that."

"We simply do not flush our toilets anymore," said Carol Shawn, whose husband, Joel, is an attorney and mayor of the Marin county suburb of Corte Madera, about 10 miles north of San Francisco.

Instead, she said, their six-member family sayes its bathing water and dumps it down the toilet. The procedure has become commonplace throughout the community of 9,000 people since water rationing went into effect there Feb. 1.

At the Montgomery Ward store in Corte Madera, 242-gallon tubs are selling briskly at $84.95 each. "People are taking their washing-machine water and pumping it out to the tubs and then using it to water their plants," said Nori Hoag, a Wards saleswoman.

"Everyone we know takes this very seriously," said Pat Williams, a Corte Madera fireman. Like other residents, Williams displays his latest water bill the way some persons show visitors a college diploma.Last month Williams' three-member family cut its water consumption in half.

"You go out on Sunday mornings and people are reading the water meters before they pick up their newspaper," Williams said as he gingerly stepped out of a shower stall lined with five-gallon, white plastic buckets. A friend who is a baker used to store raspberry jam in the buckets, he said. Now they catch the used shower water, which Williams uses in the toilet.

Williams' fire department has not had a "wet" practice session in months and he said the company will begin training sessions next month in how to save water while putting out fires.

"It's a whole new way of life and sometimes it gets kind of absurd," said William Laurie, a homeowner in the Marin County suburb of Mill Valley. "You go to a party and people bring their own water. And when you head for the bathroom, they look at you like you're gonna rob the place."