A Preliminary Survey by the Utah Seismic Safety Commission and Structural Engineers Association of Utah
Utah faces a serious risk of a major earthquake. The most serious threat is a magnitude-7 rupture of the Salt Lake City segment of the Wasatch fault that could kill 2,300 to 2,900 people, injure 30,000 to 40,000 more and cause damage and other losses totaling $37 billion. Other Utah faults also could produce strong, destructive quakes.
The Utah Seismic Safety Commission (USSC) and Structural Engineers Association of Utah (SEAU) used a method known as “rapid visual screening” to make a preliminary assessment of the earthquake safety of a sample of 128 school buildings out of more than 1,000 schools in the state of Utah. The Utah Schools Rapid Visual Screening Pilot Project was funded by $69,000 in grants from the Federal Emergency Management Agency (FEMA).
Of the 128 public and charter school buildings screened using these so-called “sidewalk surveys,” 51 were determined to have an acceptable level of seismic safety, but 77 school buildings – or 60 percent – were found to require more detailed seismic evaluation to determine if they can withstand strong earthquakes or instead need to be retrofitted or replaced.
Of the 77 school buildings needing further evaluation, 46 scored poorly enough that the screening guidelines suggest they are at least 10 percent likely to collapse during a major earthquake, and the scores of 10 of those buildings indicate they are highly likely to collapse during the “big one.”
This pilot project highlights an urgent need to conduct rapid visual screening of all of Utah’s 1,000-plus schools to determine which meet seismic safety standards and which require more detailed seismic evaluation of the possible need for seismic retrofitting or replacement.
It is hoped that this survey of a sampling of Utah schools leads to rapid visual screening of all Utah schools for seismic safety, and to a broader goal of establishing a systematic program – for public and charter schools statewide – that deals with the very real problem of the earthquake safety of Utah’s large number of older, seismically unsafe schools and other buildings.