The Ukiah Daily Journal reports that the county's Board of Supervisors on Tuesday voted unanimously to make the declaration, citing an "imminent threat of disaster" from drought conditions.
The state Department of Water Resources said Mendocino is the first to request state drought assistance.
Officials hope the declaration will result in state funds and assistance in developing a drought plan.
Gov. Jerry Brown has convened a task force to help decide if a statewide drought emergency is warranted.
State water managers say they will be able to deliver just 5 percent of the water sought by municipal agencies and nearly a million acres of farmland.
(AP) - While much of California remains in the grips of extreme drought, spring storms have eased pressure slightly and reduced the number of rural communities considered at risk of running dry.
The annual report on California's Air Quality has just been released, and the drought is listed as a major factor this year.
Rain and snow may not have pushed California out of its drought, but the late season precipitation will mean a little more water for State Water Project users. There is also relief for some federal Central Valley Project users.
A new survey finds Californians are split over the cause of the state's drought.
Hundreds of waterfalls are cascading throughout Yosemite National Park, but they may not last too much longer.