The Bhutanese Leading the way.
The overtopping of the 1,020-MW Tala Hydropower Project, the single largest revenue-earner for Bhutan is more than an isolated technical failure. It is a wake-up call on operational discipline, maintenance culture, and accountability in one of the country’s most critical infrastructures.
According to officials, the overtopping occurred after power supply to the dam failed in the early hours of 5 October 2025, preventing operators from fully opening the spillway gates. The back-up diesel generators meant to restore power automatically could not deliver power in time.
Within minutes, flash floods from the Lubichu and Tichhalumchu streams overwhelmed the structure, sending water cascading over a dam never designed for overtopping.
Hydropower experts say the damage could be extensive: the power packs and hydraulic systems that control the gates have been destroyed, the downstream apron may have been scoured, and debris and silt now clog the 92-metre dam. Restoring the plant could cost hundreds of millions of ngultrums and lost generation and the accumulated losses could even cross a billion if not more.
The Druk Green Power Corporation has begun restoration and assured that the situation is under control. Yet questions remain which must be answered in due time.
It is vital that DGPC and the Ministry of Energy and Natural Resources conduct a transparent technical audit securing all digital logs, event records, and maintenance files before repairs proceed.
Bhutan’s hydropower success was built on engineering excellence and discipline. The Tala incident must therefore serve as a turning point to strengthen safety culture, ensure qualified leadership, and enforce accountability not through blame but through proof and reform.
Our dams generate the nation’s lifeblood. They must never be left at the mercy of human error or preventable neglect.
“By failing to prepare, you are preparing to fail.” – Benjamin Franklin
At a time when dam safety is a global priority and rainfall intensity s are increasing due to climate change, dam owners need to remain especially vigilant.
Key questions arise:
1. When was the last comprehensive safety review conducted?
2. Were there flood monitoring stations installed on the two streams that contributed to the sudden rise in inflows?
3. If so, was it measures and communicated ?
4. Were there any provisions in place for manual gate operation in the event of power failure?
5. How was the silt level monitored, and when was it last measured?