NAPA (CBS SF) — A moderately strong earthquake shook the San Francisco Bay Area early Sunday morning, injuring over 170 people in the Napa Valley, severely damaging historic buildings in downtown Napa, rupturing gas lines and water mains across Napa, Sonoma, and Solano counties, leading to multiple fires, plunging thousands into darkness and buckling and cracking roads on Highway 37 and State Routes 12 and 121.

Nearly 100 aftershocks were recorded following the earthquake, the largest to hit the Bay Area since the 6.9 magnitude Loma Prieta quake nearly 25 years ago. Initial reports had the earthquake measuring 6.1 magnitude before revising it to 6.0, and then upgrading it back to 6.1.

At least 170 injuries including six critical injuries to adults and a child. The child was airlifted to another hospital for specialist care after being severely injured when a fireplace collapsed.

Walt Mickens, President and CEO of Queen of the Valley Hospital, said “The majority of injuries are non-life threatening: lacerations, cuts, abrasions, bumps and bruises. One patient has multiple fractures. One heart attack. A handful are being admitted to the hospital. Most are treated and released.”

The hospital has some structural damage and leaks, but the doctors were able to continue to care for the onslaught of patients and set up an on-going triage.

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Napa City Councilmember Peter Mott reports the library and the historic Chinese laundry building suffered significant damage, and bricks and glass are scattered across downtown sidewalks on Second and Third Streets. The old courthouse in Napa has significant damage to the brick as well.

At least four mobile homes in Napa burned to the ground, and six to eight others were damaged at the same mobile home park. The older homes sitting on blocks slipped off, rupturing gas lines, and sparking fires.

Water mains in residential areas are broken, causing some localized street flooding.

All major Bay Area bridges have been inspected and concluded to be safe.

The U.S. Geological Survey’s automated economic loss software predicts losses above $100 million.

Significant damage was also reported in nearby Vallejo, where costs were estimated at over $5 million.

A significant aftershock of at least magnitude 5.0 is likely in the next seven days, with U.S. Geological Survey scientists forecasting a 54 percent chance. There is a 5 percent chance of another quake greater than 6.1.

As the first major earthquake to hit the Bay Area in the age of smartphones and social media, photos and damage reports quickly surfaced moments after the quake.

CAUGHT ON TAPE: Hercules Family Records Quake



The CHP closed State Road 37 from Sonoma Blvd to Fairgrounds because of possible roadway damage.

#UPDATE SR-37 Closures: WB off-ramp to Sonoma Blvd Closed, WB I-80 to SR-37 closed at this time. Other SR-37 roads open. @CaltransD4 enroute — CHP Golden Gate (@CHP_GoldenGate) August 24, 2014

KCBS’ Todd Smoot reported at 4 a.m. that a Safeway store in Sonoma had no power, and all employees evacuated the store while firefighters checked inside. The shaking was especially strong there because of the nature of the land being on alluvial gravel, sand and silt deposits.

#Napa SR-12/121 at Cuttings Wharf – Damage reported to roadway, affected sections coned off. Be careful in area — CHP Golden Gate (@CHP_GoldenGate) August 24, 2014

Callers to KCBS Radio reported a significant shaking motion in the city of Napa, lasting for an extended time.

In Contra Costa County, the quake was felt as a long, rolling, shaking motion with several peaks of movement lasting for an extended time.

People as far away as the South Bay and Davis reported being woken up by the quake, which was centered 6.7 miles beneath Earth’s surface.

Within minutes, more than 600 people had commented on the CBSSF initial Facebook post about the quake.

“EVERYONE in Petaluma is up and chatting on Facebook. We definitely felt it!” said Ann Popovic.

“(It) Scared me. I’m still scared. Lasted a really LONG time,” said Valerie Gunnell on Facebook.

“Woke up south San Jose,” said Brianne Laiwa.

“Now that was a real earthquake,” exclaimed San Francisco Sunset district resident Matt Wandell.

As you might imagine, the rumbling set off an explosion of tweets:

Damage from #earthquake to my sister's kitchen in #napa .Thankfully nothing to major in this room of her apartment. pic.twitter.com/yMUbztKSlu — alicemassimi (@avmassimi) August 24, 2014

#earthquake in SF Wow – that was a whopper. — Liam Mayclem (@liammayclem) August 24, 2014

Woke up to our apartment shaking back and forth! Scariest moment of my life! #earthquake #sf — Julia Engel (@GalMeetsGlam) August 24, 2014

What that looked/felt like for in laws in Napa. #earthquake pic.twitter.com/avTYVedRkn — Andrew Crookston (@acr) August 24, 2014

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