Californians cut their water use by a "dismal" 2.8 percent in February, officials said Tuesday, days after the state's governor demanded 25 percent reductions to counter a historic drought.

The cut compared to the same month in 2013 was the lowest since California began recording reductions in response to the western US state's worst drought since records began, now in its fourth year.

"Today's ... results are very disturbing and provide even more support for the governor's call for an immediate 25 percent mandatory reduction in urban water use statewide," said State Water Board Chair Felicia Marcus.

"Californians need to step up now -- especially those who have not been doing their share .. We are in a drought like we've not seen before, and we all need to step up like never before," she added.

It said the "dismal conservation rate is the lowest monthly figure since the State Water Board began tracking the data in July 2014."

Governor Jerry Brown last week announced sweeping statewide water restrictions for the first time in history in order to combat the region's devastating drought.

Despite the drought -- which has seen lakes and reservoirs sink to historic lows -- many Californians continue to water their lawns and fill their swimming pools as if nothing was happening, according to a recent study.

On average wealthier neighborhoods like Beverly Hills consume three times more water than less affluent ones, according to the study by researchers at the University of California Los Angeles (UCLA).

"With income and water use so tightly bound together, further incentive must be given to higher water users -- and thus higher-income customers -- to conserve more," said the study.

Brown's 25 percent reductions would be achieved by ramping up enforcement to prevent wasteful water use, while investing in technologies designed to make California more drought-resilient.

The order also set out new measures to reduce water use, including the replacement of 50 million square feet (4.6 million square meters) of lawns with drought-tolerant landscaping.

The measure orders campuses, golf courses, cemeteries and other large consumers of water to significantly cut use.

The drought has left swathes of California's landscape unrecognizable, with normally brimming lakes and rivers now dry and losses to the state's agricultural industry estimated at several billion dollars.