Pipe corrosion blamed for 2025 Saitama sinkhole, north of Tokyo
An expert investigation committee has concluded that corrosion in a sewer pipe caused the sinkhole that opened in Yashio, Saitama Prefecture, north of Tokyo, in January 2025. The committee released its final report Thursday, Jiji Press reported.
The report noted that while increased risks of corrosion and damage could have been anticipated with closer monitoring, the sinkhole itself was not necessarily predictable.
The accident occurred at around 9:50 a.m. on Jan. 28, when the center of an intersection collapsed, swallowing a truck.
The 74‑year‑old driver and his vehicle were trapped in the sewer pipe below. Rescue operations were hampered by sewage and hydrogen sulfide, and the driver’s body was recovered from the deformed truck cabin about three months later.
According to the findings, the Saitama prefectural government failed to obtain images of the sewer pipe during a 2021 camera survey, leading to an underestimation of corrosion risks.