AIR Worldwide Estimates Insured Losses for September 7 Chiapas, Mexico, M8.1 Earthquake
The highest magnitude earthquake to affect Mexico in a century struck off the coast of the state of Chiapas at 11:50 p.m. local time, September 7. The M8.1 earthquake was located about 1,000 km from the capital, Mexico City.
Mexico City came through without experiencing major damage, although buildings swayed and residents ran into the streets. A highway under construction to the city’s new airport partially collapsed, and windows at the existing airport shattered.
The states of Oaxaca and Chiapas were hardest hit and have experienced numerous aftershocks, dozens of which were M4.5 or greater; at least 96 people were killed. According to federal officials, 12,000 homes were damaged in Oaxaca. The number of destroyed homes reported ranges from 971 in Oaxaca to 5,000 to 7,000 in Juchitán alone. All sources agree that Juchitán, which is located on what is commonly known as the Isthmus, was the worst-hit city in Oaxaca. In Chiapas, the damage was far greater overall: the Chiapas Civil Protection Agency reports that more than 54,000 homes were damaged, about 37,000 of which experienced partial damage, and nearly 18,000 of which collapsed. The state authorities also report that there were 97 municipalities affected, mainly Tonalá, Villa Flores, San Cristóbal, Cintalapa, and Jiquipilas.
In Chiapas, at least 98 healthcare facilities and 129 public buildings were damaged. Many roads, highways, and bridges were also affected.
AIR’s loss estimates explicitly capture damage from ground shaking. Losses include insured physical damage to onshore property (residential, commercial/industrial), both structures and their contents, and auto. Note that AIR’s estimates of insured losses are based on assumptions about take-up rates in Mexico (the percentage of properties actually insured against the earthquake peril), about which there is considerable uncertainty. Please note that total economic losses are expected to be much higher than industry insured loss estimates. The range in AIR’s loss estimates reflects uncertainty in the slip distribution at the fault, modeled ground motion, and damage estimation.