(Bloomberg) -- Wildfires that tore through northern California’siconic wine-growing regions have prompted evacuations of more than20,000 people, killed 11 and damaged some of the most valuablevineyards and wineries in the U.S.

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Blazes are sweeping through one of the state’s most scenic andtreasured destinations, threatening the livelihoods of tens ofthousands of people. California’s wine industry drew 23.6 milliontourists and sold $34.1 billion in retail value in the U.S. in2016, according to the Wine Institute. The Napa and Sonoma Valleysare where the highest-end wine in the state is produced.

“We are all in shock and trying to help our fellow growers andneighbors where we can,” said Heidi Soldinger, a spokeswoman forNapa Valley Grapegrowers.

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In the last 24 hours, winds fanned 17 fires across the northernpart of the state, burning more than 115,000 acres, according tothe California Department of Forestry and Fire Protection. About1,500 commercial, residential and industrial structures wereburned, and damage assessment teams have started accounting for thedestruction. Governor Edmund Brown declared a state of emergency inNapa, Sonoma and Yuba counties.

Mostly finished

The harvest in Sonoma and Napa counties is mostly finished, saidDaniel Sumner, an agricultural professor at the University ofCalifornia at Davis. Still, fires can damage grapes yet to becollected and can also destroy vines and wineries, he said.

“It’s bound to be a significant and substantial impact on thehigh-quality wine industry,” Sumner said.

The latest wildfires are among California’s five most damaging,Aon says

Jennifer Putnam, chief executive officer of the Napa ValleyGrapegrowers, said 80% of the county’s crop has been harvested. Howlong smoke lingers will help determine whether grapes on the vineare tainted, she said.

“This was going to be a big week,” she said. “A lot of the fruitstill hanging is high quality cabernet.”

In Sonoma, about 90% of the crop has been harvested, though somewinegrapes were scheduled to be picked in the next 10 days,according to Karissa Kruse, president of Sonoma County Winegrowers.Reports of fire damage to wineries, businesses and homesare mounting. About 6% of Sonoma’s 1 million acres is grapes,Kruse said.

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A fire burns at a Hilton hotel on Monday, Oct. 9, 2017, inSanta Rosa, Calif. Wildfires whipped by powerful winds sweptthrough Northern California sending residents on a headlong flightto safety through smoke and flames as homes burned. (AP Photo/BenMargot)

Constellation brands shuts Napa wine tasting rooms as firesrage

While Sonoma and Napa produce about 10% of California’s wines, it’sthe most valuable region in the country, said Stephen Rannekleiv, abeverage analyst at Rabobank International. Most grapes in thestate are grown in the San Joaquin Valley, where cabernet sauvignongrapes go for about $400 a ton.

The same fruit from Napa Valley usually costs closer to $7,000a ton, and can sell for as much as $50,000. High-endwines are driving demand growth in the U.S., with bottles pricedover $10 seeing the biggest gains, Rannekleiv said.

“That’s why it’s so devastating — so much of the value iscreated there, and incredible investment has gone in there,”Rannekleiv said by telephone. “It’s the face of the California wineindustry.”

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Pictures flooded social media showing burned-down buildings inthe region. Paradise Ridge Winery in Santa Rosa was among thosethat burned down, according to a Facebook post. Signorello Estatesburned as well, according to the Sonoma Valley Vintners &Growers Alliance.

Fires tripped several high-voltage power lines leaving tens ofthousands without electricity, according to PG&E Corp.

The French Laundry, a three-Michelin star restaurant, wasshuttered Monday due to power outages, according to therestaurant’s Twitter account. Spirits maker Constellation BrandsInc. closed its tasting rooms as well, including at Robert MondaviWinery. Phone lines at some of the region’s other famous producerswere out of commission Monday afternoon, including Whitehall LaneWinery and Martinelli Winery.

Fire burns from an open gas valve near the pool area at theJourney's End trailer park on Monday, Oct. 9, 2017, in Santa Rosa,Calif., after a wildfire destroyed nearly all of the roughly 160units in the park for residents over age 55. The homes next to U.S.Highway 101 at the northern end of this city of 175,000 were amongthose that were consumed by flames as more than a dozen firesburned statewide. (AP Photo/Ben Margot)

Vine damage

Even in vineyards where all the grapes have been collected, there’sthe possibility of fire damage to the vines themselves, said JessKoehler, co-owner of La Finquita Winery in Ramona, outside ofSan Diego in Southern California.

“It takes at least three years minimum to get a crop that youcan actually do something with — the more mature the vinegets, the higher quality the grapes, the higher quality thewines,” Koehler said. “It could have a real long-lastingimpact for everybody up there.”

In 2008, smoke from smoldering wildfires in Mendocino Countycontaminated crops of pinot noir grapes, said Bill Pauli,a grower and general partner of Yokayo Wine Co. in Ukiah,California.

“Some wines had the odor of someone who had been standing nextto a barbecue,” Pauli said in a telephone interview. “It was not agood situation and we all hope it doesn’t happen again.”

Kristine Pond reacts as she searches the remains of herfamily's home destroyed by fires in Santa Rosa, Calif., Monday,Oct. 9, 2017. (AP Photo/Jeff Chiu)

The entrance to the fire-ravaged Signorello Estate winery isseen Monday, Oct. 9, 2017, in Napa, Calif. (AP Photo/Marcio JoseSanchez)

A man walks past the front of a Kmart store destroyed by afire in Santa Rosa, Calif., Monday, Oct. 9, 2017. (AP Photo/JeffChiu)

The remains of burned down homes are shown in Santa Rosa,Calif., Monday, Oct. 9, 2017. (AP Photo/Jeff Chiu)

Rudy Habibe, from Puerto Rico, stands by the burning HiltonSonoma Wine Country hotel, where he was a guest, in Santa Rosa,Calif., Monday, Oct. 9, 2017. (AP Photo/Jeff Chiu)

A firefighter hoses down a house burning in Santa Rosa,Calif., Monday, Oct. 9, 2017. Wildfires whipped by powerful windsswept through Northern California sending residents on a headlongflight to safety through smoke and flames as homes burned. (APPhoto/Jeff Chiu)