But Michael Wara, a professor of environmental law at Stanford University, doubts the new rules can be enforced effectively. Any meaningful solution to an increasingly desperate drought, he said, will have to overhaul California's legal structure for allocating water, provide incentives for users to cut water use and build cooperation among the state's many local water agencies.
The state's system for choosing who gets how much water is antiquated, Wara said. It lacks a system for monitoring how much water is being used by many users—especially agricultural ones. Moreover, water consumers lack real incentives to conserve water the same way they conserve other resources, such as gasoline.
Water "is somewhat similar to electricity, where prices don't go up even when you have scarcity," he said, "and that is like almost nothing else that we have in limited quantities and that is so valuable."
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Others have expressed similar misgivings about whether Californians are inclined to conform to new, aggressive rules. Dave Bolland, who manages special projects for the Association of California Water Agencies, this week told California NPR affiliate KQED that he doubts people will embrace a "new water use ethic."
Another problem is that the responsibility for managing water across the state is spread out among a fragmented collection of agencies, with varied levels of funding.
Large cities such as Los Angeles have made progress in cutting water use over recent decades, but many smaller water agencies lack the resources to take the same kinds of steps, he said.
"I am very skeptical that the water agencies and the State Water Resources Control Board can enforce any of this," Wara said.
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In theory, any peace officer can cite violators, according to the State Water Resources Control Board statement. Fines for violations can run up to $500 a day for individual residential users and $10,000 a day for water suppliers.
The state is handing out big fines for users it says are not complying with existing regulations. Public records show, for instance, that state authorities fined a dairy in Turlock $73,000 last week for failing to provide annual water usage reports.
But Wara points out that the state is putting the mandatory cuts in place largely because the voluntary cuts did not work at all. That suggests many Californians either don't care enough to conserve, or don't want to make the cuts for some other reason.