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The startling projections of a quake in Salt Lake City: What you need to know

SALT LAKE CITY — It’s 2 a.m. on an April Thursday.

Along the Wasatch Front, most of the more than 2 million Utahns who live here are sleeping, at home in suburban homes or aging apartments, even as thousands of others are working graveyard shifts in hospitals or other businesses.

Then it happens. The world erupts in shaking so violent, those standing are knocked to the ground. Picture frames are hurled from walls, furniture tumbles across rooms, televisions crash down.

The land cracks, shifts and, in some areas, lifts into jagged ledges. Highways fracture. Power lines snap. Water and gas lines sever; fires roar to life. Buildings and homes crumble.

The largest earthquake to hit Utah in modern times has just struck. Its magnitude: 7.0.

"A 7.0 earthquake would be absolutely devastating, wherever it hits, in its effect on people, infrastructure — all of the things we take for granted and that we rely on every day," said Joe Dougherty, spokesman for the Utah Division of Emergency Management.

Under this scenario, the quake's epicenter hits Salt Lake County, and it ruptures along the Wasatch Fault, which runs 240 miles halfway through the state, from northern to central Utah. About 80 percent of the state’s soon-to-be 3 million people live and work in the region.

Residents from Brigham City to Nephi, and Grantsville to Kamas feel the quake, but those in Salt Lake County see the most devastation.

Minutes later, the shaking stops, but the state’s problems have just begun.

In the dusty, fiery aftermath, sirens sound. The state's roughly 10,000 firefighters, police and paramedics are following emergency protocol: They're tending to their families first, then they will assemble. But emergency managers expect only 60 percent of the region's first responders will be immediately onhand, so those 6,000 or so will face a daunting task.

If the quake hits at 2 a.m., while many sleep in unstable homes and structures, 2,487 are projected to die and more than 36,000 will be injured. If the quake strikes at midday, 1,968 would be dead, and 28,000 injured. If it comes during the 5 p.m. commute, 2,100 would be dead and 29,000 injured, according to modeling designed to identify the problems and prepare to find solutions.

In all, roughly 86,000 are expected to lose their homes.

The region’s main arteries — utilities, highways, communication — would be severed, and won’t be restored for weeks and, in some areas, even months to come. How likely is it to happen? The main water line for Salt Lake City crosses the fault line 19 times.

Federal loss-estimation software tells the Utah Division of Emergency Management that this scenario would be reality if a 7.0-magnitutde earthquake struck Salt Lake County, and scientists say geographical records show while such an event is rare, it’s not only possible, but plausible.

Expecting the Worst

The loss and challenge brought by a 7.0 quake stokes a yearly effort that urges Utahns to realize and prepare for such in event, Dougherty said.

More than 700,000 Utahns plan to participate in the annual earthquake drill, the Great Utah ShakeOut, on Thursday morning. Its twofold goal is to help people and organizations get prepared and learn how to protect themselves.

"We really want to have a culture of preparedness," Dougherty said. "Mental and physical readiness comes from doing things that get you prepared so that you have a game plan, and having that game plan gives people so much comfort, especially if they've practiced it."

Dougherty said large earthquakes are possible throughout Utah because the state sits on top of a "seismic zone," which includes the Wasatch Fault as well as the West Valley Fault, the Hurricane Fault, the Cache Valley Fault, as well as others beneath the Great Salt Lake and Utah Lake.

“We have these sleeping giants everywhere,” Dougherty said.

Keith Koper, director of the University of Utah seismograph stations, said earthquakes don’t occur like clockwork and many geological variables influence their likelihood, but the reality is that it could happen anytime.

Koper said the matter is troubling because geological records can only reveal so much, and scientists simply don’t have the capability to accurately predict when or where the next earthquake will occur. But rock records do show that they have happened in the past, and nothing is preventing ongoing tectonic activity.

“There’s a lot of uncertainty,” Koper said. “We know it’s going to happen at some point, but the problem is we don’t know if it’s going to be next year, in 10 years, 100 years, or 500 years.”

But those geological records show the Wasatch fault has a major earthquake every 350 to 400 years, Dougherty said. The region’s last? About 350 years ago.

So that’s why Bob Carey, operations chief for the Utah Division of Emergency Management, lives and breathes earthquake emergency preparedness.

“There’s a big one — that 7.0 — lurking out there; the rock record shows us that,” Carey said.

If a severe earthquake hits in the Salt Lake City segment of the Wasatch fault, it would cause the worst structural and economical devastation, with greatest loss of life, injury and housing displacement, Carey said. The shaking would result in hazardous material spills, numerous landslides, scarps (ledges that could be almost 10 feet high), and even fluid-like land activity, or liquefaction, in areas near water tables, Koper said.

Hundreds of aftershocks would also impact the area, including a 6.0-magnitute earthquake that’s expected within a day of the initial shock, Carey said.

In the scenario, the Federal Emergency Management Agency’s loss-estimation software, HAZUS, considers 12 counties — from Box Elder, Cache and Rich in the north, to as far south as Juab, Utah and Wasatch—which are all expected to be directly impacted if a quake’s epicenter strikes Salt Lake County.

Such an event would “definitely be an economic killer,” Carey said. The state would incur about $32 billion in structural loss and the subsequent economic fallout.

“Recovery is going to be excruciatingly slow,” he said. “It’s stunning. It’s so big; you almost don’t know where to start. “


Of the 757,400 buildings in the region, about 182,000 will be moderately, extensively or completely damaged — 24 percent of all buildings across all 12 counties. Of those buildings, more than 55,000 will be damaged beyond repair, according to HAZUS.

During the past decade, city, county and state funding has helped retrofit several government buildings in Salt Lake County, including the state Capitol and the Salt Lake County Emergency Center, to protect against earthquake damage, said Jeff Graviet, Salt Lake County Emergency Services director.

Laws passed in 1975 require all newly built buildings to be engineered for earthquake safety, but brick or concrete buildings built before then are considered unreinforced masonry structures, which are especially susceptible to damage, and especially dangerous if they’re multiple stories, Carey said. Those are the structures that are most likely to collapse.

“If you look around downtown Salt Lake City, you’ve got these four- or five-story unreinforced masonry apartments all over the place,” Carey said. “You could very well see loss of life there.”

Graviet said no legislation is in place requiring businesses or homeowners to retrofit those susceptible buildings, and it's up to the owners to absorb the expense if they choose to invest in protection. Salt Lake City leaders launched a "Fix the Bricks" initiative in 2012 to encourage those owners to invest in reinforcement, but Dougherty said almost 50,000 buildings in Salt Lake County are still considered unreinforced masonry.


Rocky Mountain Power is expected to shut down the entire region’s power grid for the first 24 to 48 hours after a major earthquake for safety evaluation, Carey said, so the first couple of days will be spent completely without power.

Dougherty said if the quake hits in the middle of winter, thousands of Utahns will be immediately seeking shelter and warmth, so emergency managers will be scrambling to set up warming stations wherever possible. He said families are encouraged to store generators in their home to help stay warm after the initial shock.

After one week, 75 percent of households are expected to have power, but it will likely be spotty due to aftershocks, Carey said.

While he said power could be “hit and miss” for some time, it will be a problem that will be much quicker to repair than damage to potable water and sewer infrastructure.

“We’re pretty much certain that nobody’s going to have water for a long time,” Carey said. “It’s going to be a very prevalent problem.”

While damage will be worse near the quake’s epicenter, it will still propagate throughout the region, because it only takes “inches” of movement to shear sewer pipes and other utility pipes, Dougherty said. Even worse would be damage to a dam — in Salt Lake County’s case, Mountain Dell Dam — which would result in a devastating flood.

For potable and wastewater, HAZUS predicts more than 17,000 leaks and 10,000 breaks across the region’s infrastructure. Carey said Salt Lake County would likely be experiencing 95 percent outages, while about 62 percent of households throughout the entire region will be without potable water. But even after 90 days, HAZUS predicts more than 40 percent of the region’s households still won’t have potable water.

“Imagine multiple water main breaks in every city that’s affected,” Dougherty said. “It would be widespread.”

Randy Bullough, Salt Lake City Department of Public Utilities water distribution and maintenance manager, said because of that widespread damage, every water district in the region will be competing for the same repair materials, and “there just may not be enough inventory to go around.”

“This is going to take years to get it back to where people are used to it,” Carey said.

In the meantime, water will be prioritized for emergency operations, and emergency managers will be seeking the help of the private sector—Target, Wal-Mart and other large suppliers—for bottled water, he said.

Lack of water flow will not only impact households, but also cripple businesses and debilitate hospitals, Carey said.


Power outages mean fuel will be mostly inaccessible for the first 24 to 48 hours, Carey said, because most stations rely on electricity to pump gas. Then, fuel will be prioritized for emergency operations, even though people will be scrambling to stock up, he said, so it will become more scarce for weeks , and prices will inflate.

But even with a full tank of gas, travel could be difficult for weeks, if not months to come.

Carey said state emergency managers are expecting all canyon roads — Weber, Parleys, Provo — to be inaccessible due to landslides and rock fall. All highways and freeways are also likely to be shut down, he said, because the Interstate 15 and 80 interchange, often called the Spaghetti Bowl, is a major weak point in the state’s transportation system.

“All you need is one small problem at the Spaghetti Bowl, and that shuts off all freeways,” Carey said. “You don’t need too much damage, just strategic damage, and everything shuts down.”

He said they’d be completely closed for a month at the very least for safety inspection. If segments need to be rebuilt, access will start to revive within the year, but it could take years before it’s finished.

Carey said emergency managers are also planning on all bridges that cross the Jordan River to fail, due to the area’s liquefaction potential.

“So the valley will be cut right in half,” he said.

Plus, damage to various road segments throughout the region may take up to a year or more to complete, he said, so travel will be limited to likely state roads, like State Street and Redwood Road.

That means traffic will be chaotic for the first few days, Carey said. The mess of blocked roads will cause severe congestion on whatever roads are functional, widespread power outages will cause four-way stops at every single intersection, and people everywhere will be jumping into their cars to flee to areas with more services or even reunite with their families, because commuters who travel across counties will find themselves separated from their loved ones, he said.

As for the airport, Carey said it will be initially closed because it’s located in a high liquefaction zone. If it’s not closed for damage, it will be for inspection, which could take weeks or a month before at the very least one runway could be open for commerce, he said.

In the meantime, emergency managers will request the Federal Aviation Administration to close the airspace to all air traffic and turn the control of that airspace over to the Air Operations Branch in the state Emergency Operations Center, based beneath the state Capitol, which will be utilizing the National Guard and the Civil Air Patrol to respond to the crisis, Carey said.

Depending on damage, he said, it could take years before the airport is back to normal.


Whether due to damage or overload, cellphones, landlines and Internet will go down initially. Reboot will follow the same model as power, but, Carey said, for the first few days after the quake, people will only be able to send texts or emails, because cellphone companies will be prioritizing communication for emergency personnel.

In the meantime, Utah’s lifeline for safety information will be radio, where KSL is federally charged to broadcast the emergency alert system. Media personnel will be coordinating with the Emergency Operations Center for that information, which has an array of communication devices, from high-powered radio, to satellite telephone to collect and distribute information from city, county and federal levels.

“We will help (state officials) get the word out to people what areas to avoid, what roads are closed, where they can go for water, and where they can go for help,” said John Dehnel, Bonneville Radio director of engineering.

As power is available — through generators and restoration — KSL will broadcast online, on radio and on television, Dehnel said, and when reporters tell the stories of fellow struggling Utahns, it will create a network of support that tells people they aren’t alone, he said.

Shelter and care

After the initial shock, Carey said of the 36,000 injured, 9,300 are projected to have life-threatening injuries or require hospitalization, but even in perfect running conditions, only 6,600 hospital beds will be available. The day of the quake, it is predicted only 2,500 beds will be usable, he said.

Plus, Carey said, about 53,000 Utahns will be seeking shelter out of the 86,000 displaced, since many will be staying with friends or family. But the state is only equipped to offer about 8,000 cots.

“That’s when we start looking for help,” he said.

Jan Buttrey, Utah Hospital Association disaster preparedness consultant, said the first few days after an earthquake will be trying, and hospital staff will be “doing the best they can with what they’ve got." However, plans are in place to maximize bed availability through a coalition with extended care facilities.

"We're making sure that the nursing facilities are as prepared as they can be so they'll be available if the hospitals aren't," she said.

She said outside help from federal disaster medical treatment teams probably won’t arrive for about three days. So in the meantime, hospitals will be evacuating if need be — depending on damage — setting up tents in parking lots, establishing stations in nearby buildings, and creating “casualty collection points” for people who have minor injuries so beds can be reserved for the critically injured.

But the reality that emergency care will be extremely shorthanded means able-bodied residents need to be prepared to care for themselves and their families for the first few days, Buttrey said. That’s why it’s highly encouraged that neighborhoods form Community Emergency Response Teams, which many cities offer training for, she said.

“The best thing that you can do is to be able to do is take care of yourself and your own,” Buttrey said.

The American Red Cross will team with emergency responders to help with food, water and housing. Locally, it has 19 paid staff and about 1,000 volunteers. Support will come from other states as well.

As for shelter, Carey said any place with shower and kitchen facilities — schools, churches — will be turned into refugee centers, but the state will be relying on humanitarian groups to get Utahns the help they need.

Dougherty said emergency managers will also be relying on all of the state’s religious organizations for help assessing damages and needs of people.

“Obviously the LDS Church in Utah has a huge presence and a pretty good structure for communicating to church members at stake and ward levels,” Dougherty said. “It’s going to be a huge partnership.”