Best for documentary-style reporting: Inside Japan’s Yashio Road Collapse: A Recovery Project That Could Take 7 Years

A road in Yashio City, Saitama Prefecture, suddenly collapsed on January 28 last year. A hole approximately 8 meters in diameter and 5 meters deep opened near a six-way intersection. The cause was reportedly corrosion and damage to a sewer pipe due to hydrogen sulfide generated by wastewater flowing through it. The sinkhole eventually expanded to 30 meters in diameter and 10 meters deep. At one point, approximately 1.2 million residents in the surrounding area were asked to refrain from using household wastewater systems.

“The section of Prefectural Route 54 that had been closed to traffic was partially reopened in April this year after a bridge was built over the collapsed section. The road originally had four lanes, but only two lanes have been restored so far. According to the prefecture, traffic volume has recovered to around 80% of pre-collapse levels,” said a social affairs reporter for a national newspaper.

Read Part 1 here: Yashio City Road Collapse Disaster: Nearly 1 Year and 8 Months Since the Incident — Drone Footage Reveals the Current Situation

 

This could happen to anyone

Some businesses and shops remain unable to resume operations until construction is completed. The prefecture has set aside approximately ¥1 billion to provide compensation to nearby businesses and residents.

This infrastructure crisis is not limited to the roads of Yashio City. In response to the accident, Japan’s Ministry of Land, Infrastructure, Transport and Tourism conducted special priority inspections of sewer pipes nationwide. The inspections revealed 96 underground cavities in the surrounding ground, all of which have since been addressed. Authorities also announced that a total of 748 kilometers of sewer pipes require urgent attention.

What measures are needed to prevent similar road collapses from happening across Japan? Junji Hashimoto, a visiting professor at Musashino University and an expert on aging infrastructure, offers his assessment.

“Restoration work that takes residents’ living conditions into consideration will inevitably take a long time. During this period, local authorities should establish a unified point of contact that breaks down the administrative divisions between prefectural and municipal departments, providing comprehensive support tailored to the actual harm suffered by residents. To prevent another collapse like the one in Yashio City, priority should be given to dangerous locations with large-scale infrastructure and heavy human traffic.”

It appears that residents living near the collapse site will have to wait some time before their peaceful daily lives can return to normal.

From the October 2–9, 2026 combined issue of “FRIDAY” magazine.