Japan infrastructure recovery: Flood damage repairs and river renovations

Authorities in Japan are managing the long-term recovery and infrastructure repairs following significant heavy rain events in different regions.

In Tochigi Prefecture, disaster assessments for damage caused by July heavy rains have totaled approximately 1.52 billion yen across 63 locations, primarily centered in Ashikaga City. The damage includes riverbank erosion, collapsed embankments, and road destruction. The prefecture and Ashikaga City aim to issue orders for full restoration works within the year following detailed surveys and designs. While some roads have undergone temporary repairs to ensure traffic flow, work on rivers and erosion control sites is being prepared for the dry season.

In Oita Prefecture, the renovation project for the Kusu River in Hita City, which suffered major damage during July 2020 floods, has seen its timeline extended by two years. The project is now expected to continue through fiscal year 2031. Additionally, the estimated cost has risen by 1.1 billion yen to approximately 8.1 billion yen due to surging construction material costs and the need for alternative drilling to protect local hot spring sources. The project aims to increase river capacity by widening the riverbed and deepening the channel to prevent future flooding in the Amagase Onsen area.