Acknowledging that California”s water conservation efforts are falling short as the state descends into a fourth year of punishing drought, the administration of Gov. Jerry Brown on Tuesday imposed new mandatory water conservation rules that will affect millions of people, from how homeowners water their lawns to how restaurants and hotels serve their guests.

“There have been some heroic efforts that people have taken, but we are not seeing the efforts to step up and ring the alarm bells that the situation warrants,” said Felicia Marcus, chairwoman of the State Water Resources Control Board, which approved the measures in Sacramento.

“We”re going to need to go further if it doesn”t rain,” she added.

Violations of the rules, which carry fines of up to $500, however, will be left up to local cities, counties and water districts. And so far, very few have been fining residents for wasting water.

Critics called the rules, which take effect April 15, a step in the right direction. But they said they are insufficient without more enforcement to avoid water shortages if the drought drags beyond this summer.

“At this point we are failing. We are not meeting our goals,” said Conner Everts, with the California Environmental Water Caucus, a non-profit group. “At what point do we accept that this might be the fourth year of a 10-year drought? And plan for that?”

The past three years have been the driest three-year period in California history dating back to the Gold Rush. On Tuesday, the Sierra snowpack was at 13 percent of the historic average, many of the state”s largest reservoirs and 2014 was the hottest year in California and globally, in recorded history.

In January 2014, the governor declared a statewide drought emergency and asked Californians to cut water use by 20 percent voluntarily. But the state”s urban and suburban residents have fallen short of that goal, cutting water use by only 9.7 percent between June and January, compared with the prior year.

Specifically, the rules adopted Tuesday:

The lawn watering provisions are expected to have the most impact.

Outdoor irrigation makes up 44 percent of all water use in California”s urban and suburban communities, according to the state water board, or 3.9 million acre feet out of 8.8 million total. Another 31 percent is for indoor residential use, such as toilets, showers and washing machines. And 19 percent is used by commercial, industrial and government entities, such as schools, colleges and prisons.

In the Bay Area, some water providers are already limiting lawn watering days. Customers of East Bay Municipal Utility District, for example, which provides water to 1.3 million people in Alameda and Contra Costa counties, are limited to two days of lawn watering a week, although which days are not specified.

And there is no enforcement. The district has a hotline to report violations, and it calls or sends emails to violators, but there is no ordinance on its books to allow the agency to issue fines, said district spokeswoman Abby Figueroa.

That could change starting April 14, when the district will consider tougher rules. Those will include “excessive use” fees for residents who use considerably more water than the community average, and perhaps sending staff members out to do enforcement.

In Santa Clara County, lawn watering rules vary widely.

San Jose Water Company, which provides water to 1 million residents, limits outdoor watering to odd-even days, where people whose addresses end in even numbers are allowed to water on even dates and those with addresses ending in odd numbers are allowed to water only on odd-numbered dates. But the company is not issuing fines for violators.

Morgan Hill and Gilroy allow watering only one day a week from November through March, and three days a week from April through October.

Milpitas allows two days a week. Sunnyvale, Santa Clara and people served by San Jose”s city water department, do not have days-of-the-week restrictions.

The rules passed Tuesday also require water providers to promptly notify to any property owner when they discover a leak on the property. And they mandate that water providers report every month to the state water board which days of the week they have limited watering to, and whether they are enforcing any fines or penalties on violators.

Many Bay Area restaurants already are limiting water to diners.

At Delicious Crepes Bistro in Santa Clara, which serves vegan fare and whose mission statement promises to be environmentally friendly, the staff says they are already careful with drinking water. When the drought became serious last year, they added a water-filled thermos on the counter and asked customers to serve themselves, with a sign on the wall saying “take only as much as you can drink.” The glasses next to it are their smallest, 12-ounce size.

“Originally, we poured water from a pitcher into bigger glasses,” said Hanna Mityashina, 28, the cafe”s manager. “When noticed when we reduced the size of the glasses, it reduces the consumption. We want to preserve water.”

Next door at Chef Ming”s, owner Diana Lee says that serving water to customers is part of being a polite hostess. “When I got to a restaurant, I hope someone can give me water — cold water or hot tea. Do you just say, “Are you ready to order?”

She said she hopes the law is flexible enough that she can ask if the customer wants water, and not just wait for customers to request it. Already, she says, when water is left on the tables, “I throw it on my plants because I feel so guilty.”

Two of her customers, Marilyn Keever and Barbara Fairburn, say waiting for a water request is a good idea. But Keever joked that she has even better one: “If you ask for water, you have to drink the whole thing or you”ll be arrested, handcuffed and taken away.”

Mercury News staff writer Julia Sulek contributed to this story.

Paul Rogers covers resources and environmental issues. Contact him at 408-920-5045. Follow him at