Beverly Hills uses its own tiered-pricing system for its water use. The city government is holding it back from the rest of its water use restriction program until the matter is resolved in order to ensure compliance with the law, according to Therese Kosterman, a spokesperson for the city.
While tiers aren't the only conservation measure available to cities and localities, some say regulators need them amid limited options in the crisis.
"The most important thing is that to get through this historic drought, we are going to have to call on Californians to do a lot of different things, and local agencies are going to need as many tools as they can have," said Michael Lauffer, chief counsel for the State Water Resources Control Board.
"We are encouraging local agencies to continue their efforts to send the right price signals. There are local agencies who have adopted block rate structures they think are completely defensible, and this court decision doesn't set those aside," he said. "This was really about San Juan Capistrano."
In a statement, Gov. Jerry Brown chided the ruling. "The practical effect of the court's decision is to put a straitjacket on local government at a time when maximum flexibility is needed," he said. "My policy is and will continue to be: employ every method possible to ensure water is conserved across California."
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Yet charging different people different prices is just one of several wrinkles in water-use laws and enforcement that Californians need to iron out. Part of the battle will be updating or overturning old policies that exist in various parts of the state, observers say.
Sacramento, the state's capital and a city of slightly less than 500,000 people, had previously prohibited water meters on houses in its city charter until the state finally passed a law overturning it, UC Davis' Frank said. The city has been installing meters since then, but they have not reached all of the houses in the area. The city government expects the project to be completed by 2025.
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A lack of meters in certain regions may complicate demands for citizens to restrict the amount of water they're using, a feature of new conservation regulations. Under the governor's new order, residential and industrial consumers are required to reduce water consumption by 25 percent of what they used in 2013. This threshold does not apply to agricultural users, however, which account for 75-80 percent of all water used in the state.
Many California communities already have strict water-restriction measures in place, and have for a long time. Many houses come equipped with low-flush toilets and special shower heads in bathrooms meant to conserve water, for example.
"What the governor's announcement does is give cover to local officials who might have been reluctant to impose restrictions, now they can say, 'Golly, we have no choice,' " said Sherry Bebitch Jeffe, a professor at the University of Southern California. "The bottom line here is not whether local communities pass restrictions, it's how will they be enforced."
Frank also said the difficulty of enforcement is the other main challenge to conservation efforts. "In California the resources dedicated to enforcement have always been very limited, and that deficiency is coming into starker contrast now that the crisis is so great," he said.
Lauffer said existing regulations already capture a lot of "low hanging fruit," and the State Water Resources Control Board directly enforces rules about water conservation affecting larger industries, such as the hospitality industry. Enforcement on a local level is carried about by the roughly 400 water agencies in the state, who can ticket violators or even take them to court.
"There are plenty of examples all over the state—Sacramento, the Santa Clara Valley Water District—undertaking a significant hiring effort to bring inspectors on board who can go out and help with that code enforcement." Lauffer of the State Water Resources Board said.
"And it is not a 'one-and-done' situation. People are trying to educate their customers, give them notice, and if they see repeated bad behavior, they are issuing fines and penalties," he added.