TOKYO - A two-story wooden house collapsed in Tokyo’s Suginami Ward on the night of September 30th, with experts suggesting that the ground beneath the property, rather than the building itself, gave way, likely due to a cracked retaining wall.
Real estate appraiser and first-class architect Osamu Kimura, who also conducts seismic assessments in the area, said he had never before seen a retaining wall collapse in this way. “It was quite a shock,” Kimura said, after visiting the site on October 1st. The house stood on sloping ground near Zenpukuji River, supported by an aging retaining wall about 4 to 5 meters above the adjacent land, which is occupied by a large apartment building. Local residents said the house, estimated to be 30 to 40 years old, collapsed toward the apartment side.
Footage from the scene showed debris completely blocking a narrow road, with the house’s interior reduced to fragments. Kimura explained that the collapse appeared to be triggered by ground failure: “The building itself was old, but it was the soil that gave way, carrying the house down with it.”
Neighbors recalled hearing loud crashing noises and watching the structure fall “almost in slow motion.” Some noted the house already had cracks, while others said the retaining wall had bulged and developed fissures. Kimura confirmed that cracks had indeed formed, likely caused by soil pressure behind the wall. He added that recent heavy downpours may have worsened the situation, as accumulated water would have added pressure to the ground.
The Suginami Ward building division had previously instructed the property owner to reinforce the retaining wall. According to the ward, the owner had just found a contractor able to carry out the work when the collapse occurred. Asked whether authorities could have acted sooner, Kimura noted that the retaining wall was privately owned, limiting the scope of government intervention. “Unless there is clear legal justification or obvious imminent danger, stronger administrative action is difficult,” he said.
Commentator Patrick Harlan contrasted Japan’s emphasis on private property rights with practices abroad. “In Europe or the U.S., once there’s a risk to public safety, community interests take priority,” he said. “I wish repairs had been carried out first, with costs and rights settled later.”
Kimura emphasized that the ward had already issued guidance and that preparations for repairs were underway, calling the collapse an unforeseen incident. Footage from January had also shown cracks in the retaining wall, raising questions about whether preventive action could have been taken earlier. Authorities are expected to review the case and consider future measures to prevent similar accidents.
Source: FNN
