Folsom Lake, a reservoir located northeast of Sacramento, has seen its capacity dwindle

California’s record-setting drought is touching the heart of Silicon Valley.

With the rainy season ending with hardly any rain to show for it, the city of Mountain View, home to tech giant Google, declared last week a water shortage emergency. In the tech-heavy city, the impact of the emergency declaration is light. Restaurants, for example, cannot serve water except upon request.

Drive or fly just a few hours inland from Apple’s home town in Cupertino, however, and the impact of the drought hitting the US’s most populous state and biggest agricultural industry is far more menacing.

For a brief moment in February and March, light rains fell, giving grape growers in Napa Valley, lettuce farmers near Salinas and suburban and rural homeowners a glimmer of hope for an end to a drought now entering its third year.

But following the driest year on record for California since data were first compiled and with little more rain expected until autumn, the situation is bleak. Water authorities believe 2014 could be the fifth or sixth driest on record.

“It looks like there is no relief in sight,” said Peter Gleick, president of the Pacific Institute, an environmental research group.

Farmers who produce more than 15 per cent of the US’s agricultural crop output will continue letting land lie unfarmed and struggle to maintain plants, such as grape vines and almonds, that take years to mature and die without constant water.

Mike Wade, executive director of the California Farm Water Coalition, said farmers are planning to fallow about 800,000 acres out of 8m acres of irrigated farmland in the state. “Everyone’s kind of holding their breath on what the summer will bring,” he said.

Some remote towns are close to running out of water, while many major reservoirs are less than half full. For the millions of Californian households in dry suburban and rural areas, it means higher than average risk of wildfires – hundreds of which have already struck this year.

Data out last week confirmed that California’s snowpack, whose melting runoff provides one-third of the water used each year by the state’s cities and farms, is near a record low, with only about one-third the amount of snow stored as usual. This time of year is usually when the snowpack is at its annual peak.

The state’s grape harvest, crucial to its multibillion-dollar wine industry, is likely to be smaller this year than usual because of the drought, growers say.

The agricultural heartland of the San Joaquin Valley usually gets about nine inches of rain a year.

“I don’t think were going to hit four,” said Nat DiBuduo, president of Allied Grape Growers, a grape farmers association.

Further west of the valley, dry irrigation canals means growers are struggling to water their vines with salty well water, he said.

In northern Napa Valley, growers say recent rains have helped but many still worry about having enough water to pump through their vines to keep them warm during the cold snaps that could come in the coming weeks.

Whether the drought leads to higher produce prices for consumers in California and beyond remains unclear, but the state’s residents have been warned to prepare for fires.

Parched forests have already led to nearly three times more wildfires than usual in 2014 alone, with the California Department of Forestry and Fire Protection (Cal Fire) fighting about 800 fires in the past three months.

Among those fires was a blaze near the southern city of Los Angeles, which was sparked by a campfire and forced more than 3,000 people to evacuate their homes.

With substantial property development in areas bordering forests throughout the state, insurance underwriter Verisk estimates that 15 per cent of California’s housing stock, of 2m, is at high risk.

Daniel Berlant, information officer for Cal Fire, said early preparation is crucial. He said extra seasonal firefighters were being recruited months in advance and seasonal fire stations typically manned in the summer will open early.

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