Verisk puts Kumamoto quake insured losses at up to $2.1b

Ground shaking and liquefaction affected residential, commercial and industrial property.

Verisk estimates insured losses from the magnitude 6.8 earthquake that struck Japan's Kumamoto Prefecture on 28 July will range between $1.4b and $2.1b, before any recoveries under the country's earthquake insurance programme.

The catastrophe modelling firm said the estimate covers insured property damage caused by ground shaking and liquefaction. 

It includes losses to residential, commercial, industrial and mutual property risks, covering both buildings and contents.

The earthquake struck near Kumamoto City on Kyushu Island at a shallow depth of about 10 kilometres, according to the US Geological Survey. 

It occurred along a shallow strike-slip fault within the Eurasian Plate. The area was also hit by a series of major earthquakes in 2016, including a magnitude 7.0 mainshock that caused extensive damage and loss of life.

The latest earthquake caused widespread damage across Kumamoto Prefecture, with the strongest shaking recorded in Uki City and Hikawa Town. Authorities reported hundreds of damaged homes and commercial buildings, as well as damage to cultural sites and public infrastructure. Assessments of structural damage are continuing.

Transport services were also disrupted after highways, bridges and railway infrastructure were damaged. Around 48,000 households lost power shortly after the earthquake.

The earthquake also affected one of Japan's key manufacturing regions. Several semiconductor, electronics and automotive plants temporarily halted operations whilst inspections and damage assessments were carried out, raising concerns over supply chain disruptions.

Verisk said most of the insured losses are expected to come from damage caused by ground shaking, with a smaller share linked to other earthquake-related hazards. 

The estimated loss range reflects uncertainty over factors including fault slip distribution, ground-motion intensity, damage estimates and earthquake insurance penetration in Japan.