While 70 percent of Puerto Rico still lacks electricity after Hurricane Maria, states like Texas and Florida continue to recover from the devastation left by Hurricane Harvey and Irma, respectively. In the past two months alone, four large-scale natural disasters have wreaked havoc across the nation. Similar events have devastated countries worldwide this year- flooding in India and Nepal, a mudslide in Sierra Leone, earthquakes in Mexico and avalanches in Afghanistan have killed thousands, and displaced even more.
A recent Forbes article dispels the misconception that these disasters are correlated, but earthquake-prone Utah can’t quite sign off the possibility of a major natural emergency. According to the Utah Seismic Safety Commission (USSC), every 300 years an earthquake of around 7.0 in magnitude hits one of the five segments of the Wasatch Fault running through central Utah. In the segment of the fault within Salt Lake City, these large quakes occur every 1,300 years. And it’s been just that long since the last one- enough time for strain energy to build up for another, according to the Commission. For the 80 percent of Utah’s population that lives within 15 miles of the Wasatch Fault, this could spell trouble.
Unbeknownst to most, Utah’s a regular victim to smaller magnitude earthquakes. In just the last two weeks, we’ve experienced 11 earthquakes.
SOURCE: Earthquake Track
Since 1850, our state’s experienced more than 55,700 quakes- that’s close to 350 a year, almost one a day. And as we chart these earthquakes over time, the prevalence and impact of each render the area around the Wasatch Fault more susceptible to damage.
SOURCE: U of U Seismograph Stations
In 2015, the USSC carried out an extensive report exploring the potential effects of another Magnitude 7.0 earthquake in Salt Lake City. And while the findings spell out extensive potential damage, Kristine Pankow- Committee Chair of the University of Utah Seismograph Stations, and co-author of the report- says the true point of the report is to measure resiliency.
“It’s about how quickly we can bounce back,” she said. “Compare the recent natural disasters in Houston and Puerto Rico. Houston is bouncing back faster because it’s part of the continental United States, and it’s dealt with storms like this before. But Puerto Rico is isolated, has issues with its power grid… and it’s just not bouncing back as quickly.”
Utah’s in a relatively good position to address the issue of resiliency, though. Three separate organizations- the University of Utah Seismograph Stations, who charts seismological data; the United States Geological Survey, who collects geological data; and Comprehensive Emergency Management, who focuses on emergency response, are together represented by the Utah Seismic Safety Commission in legislative issues.
With the guidance of national organizations like the Federal Emergency Management Agency (FEMA), Utah’s well on its way to establishing resiliency, that vital ability to bounce back from a large natural disaster. But what exactly are we up against?
Widespread damage is probable, and substantial
In the event of a Magnitude 7.0 earthquake, the authors of the report estimate $31 billion in short-term economic loss: damage to buildings, schools, roads, bridges and utilities (like water and electricity). This damage is more extensive than a few crumbling walls. According to the report, other physical effects include rupture of the ground surface (up to 8 feet vertically); widespread liquefaction of the Salt Lake valley, causing the soil to shift and slide like liquid; landslides and rockfalls; and potential flooding by the Great Salt Lake, depending on lake level.
This loss estimate doesn’t include human impact, the Utahns requiring medical attention or accommodation after building damage. Approximately 84,400 households could be displaced with around 52,700 individuals seeking temporary shelter, since some Utahns will have accommodation options other than shelters (like staying with family members or friends). Additionally, life threatening injuries could rise as high as 9,000, and even the largest hospitals in the state may not have enough empty beds or staff to accommodate such numbers.
With prospective damage this great, how resilient can Utah be? How prepared are we in the face of crumbling buildings, collapsed highways and hospitals overrun with injured patients?
For these answers, stay tuned. In this project’s second segment we’ll explore Utah’s preparedness, and what you can do to help ensure your safety when the next quake strikes. And if you’d like to see and play with the data used, check out my repo here.