California Gov. Jerry Brown declared a drought emergency in the state on Friday, emphasizing what area water experts have warned locals about. 

Brown's announcement comes as state reservoirs reach critically low levels and cities across the state have instituted water-rationing measures, the Los Angeles Times reports.

Speaking at a San Francisco news conference, Brown also called on "all citizens" to cut back "at least 20% of their water use." He was flanked by charts and photos showing the state's anemic precipitation and snowpack.

"We ought to be ready for a long, continued, persistent effort to restrain our water use," Brown said, adding that conservation efforts would be "voluntary."

Lawmakers, farmers and activists have been urging the governor to take the step for weeks, according to The Times.

Nearly 85% of California was categorized as experiencing a severe drought in December 2013, according to the U.S. Drought Monitor analysis.

In La Cañada Flintridge, the city receives 50% of its water from the Colorado River and Northern California, said Foothill Municipal Water District Board President Richard Atwater, who was recently appointed to the National Academy of Sciences Committee, in an interview with the Valley Sun. 

The foothills area is very vulnerable to droughts, so water conservation and reuse is therefore crucial for the community, Atwater explained.

-- Nicole Charky, nicole.charky@latimes.com

Follow on Twitter: @Nicosharki.

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