"We were in the middle of doing squats with the bar lifted when the shaking started. We all just kind of looked at each other — wondering, 'Should we go on with the class?'" she said.
Moments later when the aftershock hit, she added, the gym was evacuated.
A magnitude-4.4 earthquake rattled the North Bay on Tuesday night seconds before another shaker, which officials believe was a magnitude-3.9 aftershock, occurred.
Despite the successive temblors, the North Bay was left relatively free of significant damage and injury, officials said.
Santa Rosa Mayor Chris Rogers tweeted late Tuesday that most of the 911 calls received after the earthquakes were reports of gas leaks and a few broken water lines. "Some fallen ceiling tiles, broken glass from items flying off shelves, and two stuck elevators (with no one inside)," he said.
By 7 p.m., the Santa Rosa Police Department issued an advisory that no major damage or injuries had been reported.
The temblors were centered about 2 miles northeast of central Santa Rosa, according to the U.S. Geological Survey. A preliminary map from the agency showed their epicenters were located off Parker Hill Road, north of Chanate Road, well within city limits.
Asked if the second quake was for sure an aftershock, Robert de Groot, ShakeAlert system coordinator for the USGS, said aftershocks must occur on the same fault line and within a certain proximity of the main shock to be considered an aftershock.
"It could take some time to determine but it appears it was an aftershock from everything we've seen," he said.
De Groot added that the earthquake was a fairly common-sized temblor for California.
"Magnitude 3 and 4 events happen fairly frequently. Magnitude 5 events happen less frequently, but this was sort of run of the mill," he said.
The first quake happened at 6:39 p.m. and was followed 42 seconds later by the aftershock, according to the USGS.
Seismologist Lucy Jones tweeted that the quakes were on the Rodgers Creek fault, which is part of the San Andreas system.
"Every quake has a 5% chance of being followed by a larger quake within the next three days," Jones said. "But most are only a little bit larger. When it is right on a big fault, capable of a big quake, the chance that that following earthquake will be big is a little higher, but still small."
Sonoma County and the Bay Area are home to several earthquake faults.
The Rodgers Creek fault, known as a strike-slip fault, runs from San Pablo Bay at the southern tip of Sonoma County north through Santa Rosa to Healdsburg. It is also part of the Hayward fault system.
It runs along Santa Rosa's east side — from Taylor Mountain, through Doyle Park, near Providence Santa Rosa Memorial Hospital and past the Santa Rosa Rural Cemetery.
The last big earthquake along the Rodgers Creek fault occurred 53 years ago.
Just before 10 p.m. Oct. 1, 1969, a 5.6-magnitude quake hit. It was followed about 90 minutes later by a 5.7-magnitude quake. A third temblor, 3.8 magnitude, occurred about six hours after the second, according to Press Democrat reports at the time.
There were several minor injuries, but no deaths.
According to a USGS report on the 1969 quakes, at least 74 buildings were damaged and the total loss exceeded $7 million.
Since then there have been other smaller quakes along the Rodgers Creek fault.
On Aug. 2, 2006, a magnitude-4.4 temblor struck just after 8 p.m. Its epicenter was 3 miles west of Glen Ellen along the the Rodgers Creek fault, experts said. No major damage or injuries were reported.
On Nov. 29, 2010, a 2.6-magnitude quake was reported, again, along the Rodgers Creek fault . There was no significant damage or injuries, officials said.
On Sept. 30, 2021, a 3.2-magnitude quake occurred. Its epicenter was about 2 miles east-southeast of Santa Rosa. Authorities said it caused minimal damage and no injuries.
The most-damaging earthquake to hit the North Bay region in the past decade occurred on Aug. 24, 2014, when a 6.0-magnitude shaker struck southern Napa County.
Napa County sustained most of the damage and economic losses, which were estimated at $1 billion. Sonoma County, though, declared a state of emergency and estimated its damages at $4.5 million, with more than half of the area wineries affected.
In the wake of Tuesday night's temblors, about 760 Pacific Gas and Electric Co. customers in Santa Rosa's Fountaingrove neighborhood and the city's northeast region lost power.
Electricity was restored at 8:11 p.m. The cause of the outage is being investigated, PG&E spokesperson Karly Hernandez said.
She added that crews also responded to 14 calls about gas odor.
Anyone detecting the smell of gas is urged to dial 911 or call PG&E at 800-743-5002, Hernandez said.
Shortly after the night's first quake, a dispatcher with Redcom, Sonoma County's fire and medical emergency dispatch agency, said "We're slammed," when reached by The Press Democrat.
At Coddingtown Mall in Santa Rosa, the quake prompted the evacuation of employees and customers, who remained outside for about 10 minutes, according to Lillian Ambrose, a manager for Icing jewelry store.
A few pieces of merchandise fell off the store's walls, she said, adding that only one customer was inside when everything began to shake.
"I freaked out, but the customer kind of laughed. She set her basket down and we walked out," Ambrose said.
Around 8 p.m., an employee of Whole Foods at Coddingtown was telling customers the store had closed. But, moments later, a manager advised customers that the store would open.
The employee, Abby Volz, said few items fell off shelves, no employees were hurt and everyone got out of the store safely.
"We were all in the middle of transactions — it was crazy," Volz said. "I was with another cashier and all of a sudden the whole store started shaking. She reacted really quickly, she dove under the nearest cash register."
Numerous Sonoma County residents told The Press Democrat they felt the earthquakes. The jolts stretched as far north as Mendocino County and as far south as Santa Clara County, according to various Twitter posts.
"I live in southwest Santa Rosa and both were quite significant," Ginger Schechter said of Tuesday night's quake and its aftershock. "Nothing damaged but, similar to my experience with the Loma Prieta (earthquake in 1989). This was a rolling quake that undulated quite a bit and could be felt as I stood bracing myself in my doorway."
Santa Rosa resident Cailyn McCauley said her family was having a dinner of tacos when the shaking began.
"For approximately 20 to 30 seconds, we rode the dining room table like it was a roller coaster," McCauley said. "After it calmed down, we got up to go outside when there was another quick jolt and the rumble was lower this time and the house shook for only about 10 seconds. We heard a glass crack but that was the extent of the damage."
At Flagship Taproom in downtown Santa Rosa, the pergola covering the patio swayed and conversation stopped as patrons quickly realized what was happening. Some headed to the sidewalk to get distance from the swaying building.
As the tremors ended, many people reached for their phones. Across B Street people near the Santa Rosa Mall followed suit.
Santa Rosa Mayor Chris Rogers said there were no reports of major damage or injuries. Santa Rosa received an increased number of 911 calls but "it sounds like it was mostly bumps and scrapes being reported," he said.
The city's facilities team was dispatched to evaluate city buildings and ensure there was no major damage, Rogers added.
Sonoma County Supervisor Chris Coursey, who represents Santa Rosa in District 3, said late Tuesday that it was too early to say if there was any damage to county facilities.
Coursey, who added that the Rodgers Creek fault runs underneath his neighborhood, was on a phone call in his kitchen when the earthquake and the aftershock happened.
"I let out a couple of expletives and immediately got into a doorway as fast as I could," he said. "I don't think I've ever reacted to an earthquake that way."
A couple of water bottles on his kitchen counter were knocked over and large paintings hanging on his walls had moved but his home wasn't damaged, he said.
Coursey, who has lived in Santa Rosa for 42 years and has experienced other earthquakes, said Tuesday's shakers felt like the strongest he has experienced.
The supervisor said he hopes the temblors were "just a wake up call" — reminding residents they must prepare for earthquakes just like for wildfires.
The Santa Rosa Fire Department directed residents to srcity.org/455/Earthquakes for tips on what to do to prepare for an earthquake.
Chris Godley, Sonoma County's emergency management director, said the county had received no initial reports of major damage, but authorities were handling a high volume of 911 calls following the quakes. He said he had heard no reports of major injuries, trapped people or significant structural damage.
The department sent an extra staff member to the county's fire and medical emergency dispatch center to evaluate the reports and calls for help being received there, Godley said.
©2022 The Press Democrat (Santa Rosa, Calif.), Distributed by Tribune Content Agency, LLC.
