Up to $820m in insured losses from the M7.3 earthquake are attributed to commercial and industrial properties

Insured losses to properties from the March 16 M7.3 earthquake that struck offshore the island of Honshu, Japan, will be between JPY 240 billion ($2 billion) and JPY 490 billion ($4 billion), according to Verisk.

Of that total, between JPY 50 billion ($400 million) and JPY 100 billion ($820 million) can be attributed to commercial and industrial properties.

The loss estimate includes insured physical damage to onshore property (residential, commercial/industrial, mutual), both structures and their contents, and from ground shaking, fire-following, and liquefaction.

Early reports suggest that more than 580 buildings in Fukushima Prefecture and more than 570 buildings in Miyagi Prefecture were damaged. 

Other impacts from the quake include power and water outages; damage to highways, rail lines, viaducts, and other infrastructure; short-term cancellation of some train service; and significant supply chain and production interruption for the automotive and paper industries. 

Like many previous significant earthquakes in Japan, high-frequency ground motions tend to be amplified considerably in areas with shallow soft sediments such as valleys and the coast. 

The 16 March 2022 earthquake was preceded by an M6.4 foreshock approximately two minutes earlier. The epicenter of the mainshock was located approximately 100km from the epicenter of the 2011 Tohoku earthquake.

In the past century, 33 earthquakes of M7 or greater have occurred within 250 km of the March 16 earthquake, including 7 earthquakes >M7 since the March 2011 M9.0 earthquake.

Earthquakes in the Japan Trench with relatively deep focal depths tend to produce very high ground motions in coastal areas. The Tohoku earthquake is an example of an earthquake with a relatively deep focal depth striking the Japan Trench that had very high ground motion observations.

Tohoku was not only the first subduction earthquake exceeding M8.5 in the Japan Trench since 1900, but it was also the largest earthquake to strike Japan since record-keeping began in the 1600s.

Before Tohoku, the Japan government’s seismic hazard models developed by HERP had relied heavily on historical seismicity. The Tohoku earthquake, however, clearly proved that the past was not a reliable indicator of future seismic activity; limited historical data had led to an underestimation of hazard.