JSTT’s 33rd Trenchless Technology Conference in Tokyo
Japan Society for Trenchless Technology (JSTT) held its Trenchless Technology Conference on July 9, 2026 in Tokyo. The goal of this event is to provide engineers with an opportunity to learn about the latest developments and gain a broad range of information to advance trenchless technology. Experts from various fields are invited to give presentations every year, and it 
marked the 33rd conference this year to address the theme of “Disaster Prevention for Infrastructure Facilities”. Approximately 90 people participated the event.
The first presentation, titled ‘Recent Developments in Sewerage Administration,’ was delivered by Takayuki Tsumori, Senior Advisor at the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). He discussed the government’s initiatives regarding sewerage projects, including the results of a special priority inspection of sewerage systems conducted in response to the large-scale sinkhole accident in Yashio City of Japan occurred last year due to a corroded sewer pipe. He also provided an overview of the amendments to the Sewerage Service Act. It was a valuable opportunity to hear directly about the government’s current efforts.
The second presentation, titled ‘Groundwater Level Control Technologies for Preparing for Compound Disasters Involving Earthquakes and Heavy Rainfall,’ was delivered by Takao Hashimoto, Specially Appointed Professor at Kokushikan University. Based on an analysis of the damage caused by the Noto Earthquake in January 2024 and an analysis of damage to embankments and retaining walls resulting from recent torrential rains, he explained the mechanisms behind these collapses and the technical measures that can be taken. 
Given the increasing frequency of urban flooding and related disasters in Japan in recent years, the presentation attracted considerable interest, with many questions raised by participants.
For the third presentation, we welcomed Dr. Declan Downey as a special guest, President of ISTT and former Chairman of both ISTT and UKSTT. In his presentation titled ‘A Brief History of Cured in Place Pipe and Where do we go from here?,’ he discussed the international history of CIPP, the development of the installation techniques, and his personal experiences around CIPP. The presentation also provided a comprehensive overview of CIPP, covering the history of ISTT, and the current status as well as the potential future development in various countries. The event was a great success, attracting a large number of participants from Japan’s CIPP industry who were eager to hear Dr. Downey speak.
As Dr. Downey will be stepping down from his role as ISTT President at ISTT Council Meeting in October, JSTT organized a retirement party after the conference. It was an
intimate gathering mainly attended mainly by people close to Dr. Downey, and we enjoyed catching up with one another in a warm, friendly atmosphere. At the party, JSTT presented Dr. Downey with a Japan national rugby team jersey embroidered with the JSTT logo and his name. We chose this gift not only because Dr. Downey is a huge rugby fan, but also because the histories of rugby and CIPP share similarities. Both rugby and CIPP originated in the UK, and Japan has developed in both fields under the guidance of the UK and other Western nations. Thanks to this guidance, Japan’s CIPP has reached a level where it can compete with top international standards. We presented this rugby jersey as a token of our gratitude to Dr. Downey for supporting the growth of CIPP in Japan. Japanese rugby still faces challenges—the Japanese national team has never managed to win against the England national rugby union team. JSTT will continue to support not only CIPP but also Japanese rugby, and if Japan is ever able to measure up to England in the future, we hope to share our excitement and gratitude with UKSTT!