Japan enacts bill to bolster maintenance of sewerage facilities

Parliament enacted a bill Wednesday to promote measures for proper maintenance and management of sewerage facilities in response to the 2025 sinkhole incident in the city of Yashio in Saitama Prefecture.

The bill to revise the sewerage law was approved at a plenary meeting of the Upper House, following its passage in the Lower House in May.

The revised law obliges sewerage operators to disclose the status of facility maintenance and management to encourage them to step up measures to address aging sewerage facilities.

It clearly states that the central government will stipulate diagnostic criteria for judging the soundness of sewer pipes. In addition to strengthening inspection standards stipulated by government and ministerial ordinances, it obliges sewerage operators to disclose information such as diagnostic results to local residents.

An item related to the structure of sewage facilities was also added to the law, requiring operators to make the structure easy to carry out inspections, repair work and emergency measures. Specifically, the revised law is expected to increase the number of pipes to two in places where damage would have a significant social impact.

Also at the Upper House plenary meeting, a bill to revise the road law was enacted, which features a plan to establish a system in which road administrators, including prefectural and municipal governments, and companies that bury sewer pipes underground conclude agreements and work together to investigate voids under road surfaces and patrol roads.

In the Yashio incident in January 2025, a large sewer pipe was damaged near a sewage treatment plant. With no backup pipe available, authorities asked about 1.2 million residents to refrain from using the sewerage system.