A massive sinkhole that swallowed a truck in a city just north of Tokyo earlier this year has triggered a sweeping government investigation into Japan’s ageing sewer network, uncovering 72km of pipes in “critical condition” and raising alarm over a broader crisis of neglected infrastructure.

The Ministry of Land, Infrastructure, Transport and Tourism ordered the investigation after the deadly accident in the city of Yashio, in Saitama prefecture, on January 28. Security cameras caught the moment a huge sinkhole opened in the middle of a busy intersection, swallowing roadway, pylons and a passing delivery truck.

The disaster gripped the nation over the following days, during which the sinkhole widened to 40 metres in diameter and rescuers frantically attempted to reach the missing vehicle and its driver. After one week, the rescue effort shifted to a recovery mission, although it was not until May 2 that the body of the 74-year-old driver was finally recovered.

The truck pulled out from a sinkhole is seen at the scene without its driver’s cabin, in Yashio, Japan’s Saitama prefecture, on January 31. Photo: EPA-EFEThe truck pulled out from a sinkhole is seen at the scene without its driver’s cabin, in Yashio, Japan’s Saitama prefecture, on January 31. Photo: EPA-EFE

The investigation’s findings were announced on Wednesday during a meeting of experts tasked with devising measures to stop similar accidents in the future, although an analyst has told This Week in Asia that the scale of the task is daunting as the nation’s critical infrastructure has been overlooked for too long.

“This is a topic of national importance because these pipes inevitably have an operational lifetime – for some it may be 50 years, others may last 70 years – but with so many reaching the end of that life cycle around the same time, we have to be concerned about more incidents like the one we saw in Saitama,” said Hiroo Ichikawa, a professor emeritus of urban planning and policy at Meiji University.

“It is going to be impossible to repair or replace 300km of pipes in cities around Japan in a short space of time, largely because of the immense cost, so that means we will inevitably see more sinkholes and, possibly, more people being injured or killed,” he said.

Ichikawa suggested that some local governments had failed to carry out the required maintenance of critical infrastructure, primarily due to the cost.

“Yes, making sure pipes and other infrastructure are safe is of course going to be expensive, but it is very important that the work is done or there will be accidents,” he said.

AloJapan.com