IAHR-APD Awards

Recognised for his contributions to computational river morphodynamics over a career spanning several decades. His work on the numerical modelling of river channel processes — sediment transport, bank erosion, braided-river dynamics and the interaction between vegetation and flow — has shaped the modern practice of river engineering. He was a central figure in the development of the iRIC (International River Interface Cooperative) software platform and its river-simulation solvers, adopted widely by researchers and practitioners internationally as open-source tools for river analysis. Through his teaching, his supervision of researchers now active across the region, and his long service to IAHR and its Asia and Pacific Division, Prof. Shimizu has advanced both the science and the international community of hydro-environment engineering.

Recognised for his contributions to environmental and coastal hydraulics and for his sustained service to the international water community. He holds Ph.D. and M.Sc. degrees in Civil and Environmental Engineering from the University of California, Berkeley, and a B.Eng. from the University of Hong Kong. After more than seven years of engineering practice in the United States he joined Nanyang Technological University in 1995, and has been Professor at the National University of Singapore since 2024. He chaired the joint IAHR/IWA Committee on Marine Outfall Systems (2014–2016) and represented Singapore at the ASEAN Hydroinformatics Data Centre (2022–2023). As Editor-in-Chief of the Journal of Hydro-environment Research he has been instrumental in strengthening the Division's flagship journal.

The Soyanggang Dam impounds the Soyang River above Chuncheon in Gangwon Province, at the head of the Han River system. Built between 1967 and 1973, it was on completion the largest rockfill dam in Asia: 123 metres high, with a crest some 530 metres long, holding a reservoir of about 2.9 billion cubic metres.

It was conceived as a multipurpose structure and has served as one ever since. It regulates floods on the Han River above the capital, supplies water to the Seoul metropolitan region, sustains river flows through the dry season, and generates hydroelectric power. More than half a century of continuous operation has made it the backbone of water management in the basin, and the reservoir it created — Soyang Lake — has reshaped the landscape and economy of the region around it.

The dam is recognised as much for what it represents as for what it does: a work of water engineering carried out at a scale the country had not previously attempted, and a marker of the development of Korea's water infrastructure. It is operated by K-water.