SACRAMENTO, Calif. (AP) -- Water use in drought-stricken California plunged by record levels in May, and Gov. Jerry Brown's administration cited that as proof cities can hit steep summer conservation targets they have blasted as unfair.
The State Water Resources Control Board on Wednesday released data showing urban water usage fell 29 percent in May compared to the same month in 2013. The savings were the best showing since the agency started tracking conservation last summer.
Regulators cautioned the savings may have been skewed by unusual May rains that reduced lawn watering. But they also credited heightened awareness about the four-year drought after the governor imposed sweeping mandatory conservation measures following April's record low snowpack measurement.
Every region of California had stepped up from what had been lackluster cutbacks. The southern coast, where more than half of California lives in cities including Los Angeles and San Diego, cut water use by a quarter after months of tepid savings.
"It's gratifying that far more communities are stepping up, and we want to see this much more through the summer," said Felicia Marcus, chairwoman of the State Water Resources Control Board. "It's just being prudent."
May also marked the last month of voluntary savings.
The water board assigned communities mandatory conservation targets between 4 and 36 percent compared to 2013 that took effect in June. Cities that lag face state-imposed restrictions in water use and fines.
Dozens of water departments had criticized the targets as unfair and unrealistic, saying they didn't take into account savings before the drought or ample local supplies. The city of Riverside has even filed a lawsuit challenging its 24 percent reduction target.
Marcus says May's conservation showed steep cuts are possible.
San Diego, for example, saw water consumption plummet by 26 percent even after protesting its mandatory 16 percent reduction target. City officials say they deserved credit for importing less water and increasing rates to pay for drought-proof supplies, including desalinated water.
"What is the incentive to do that if in fact we are penalized by the state?" John Helminski, assistant director of San Diego public utilities.
Helminski said May's showing was likely an anomaly caused by well-timed storms that caused residents to turn their sprinkler systems off. He expects conservation to slip this summer, but still meet the state target after the city lets parks go brown and ramps up a turf removal rebate program.
State officials will pay close attention to Southern Californian water use in summer holds to see if savings really reflect shorter showers and dry lawns instead of better weather. Temperatures in the entire South Coast region were about 5 degrees cooler compared to May 2013 with an additional half inch of rain, according to National Oceanic and Atmospheric Administration data.
The Santa Fe Irrigation District, serving small wealthy communities on hills overseeing San Diego, is among those hoping its remarkable turnaround in May wasn't a fluke. It posted a 42 percent reduction in May after water use actually increased 9 percent in April, although per-capita water use is still more than three times the state average.
District spokeswoman Jessica Parks says customers, many of whom live in large houses with sprawling lawns, now have restrictions on how much water they can use or else they'll pay steep prices.
Water use data is calculated by a survey of more than 400 California water departments and includes residential and business consumption.