KP Sharma

A project aimed at reducing slope disasters on Bhutanese roads has been successful, thanks to a five-year collaboration between the Ministry of Infrastructure and Transport and the Japan International Cooperation Agency (JICA).

Rain gauges and slope tilt sensors have been installed at three major slope failure sites in the country, namely Reutala, Razhau, and Dzokhalom, allowing the authorities to monitor slope movement and make informed traffic management and risk assessments at the sites.

The project began in 2019 and has been instrumental in curbing slope failure and debris flow, which commonly occur during Bhutan’s rainy season. With the help of the project, engineers have been able to build safe and robust roads that are accessible all year round, regardless of the weather.

The project has also piloted bio-engineering works on debris slope at Gangthangka in Wangduephodrang and Yangkil in Trongsa. The method involves planting suitable flora that can withstand debris slope failure.

The project officials have also evaluated the geology and slope stability at 46 selected pilot sites through field surveys. Based on the studies, they have revised the standards for cut slope angles for debris and rock slope failures.

Moreover, to counter rock slope failure, the project constructed an earth wall and drainage system at Chendebji and identified a second pilot site at Tekizampa, which will commence in December 2023.

The project also focused on improving the road information system to promote commuters’ safety and convenience. By April 2024, it will help update the Bhutan road safety app.

The project will be extended to other parts of Bhutan once the pilot projects are completed. The project for capacity development on counter-measures of slope disasters on the country’s roads began in January 2019 and will conclude in July 2024.