The Bhutanese Leading the way.
In a major positive development, the Indian side has agreed to some important design changes and suggestions by the Bhutanese side in terms of the stabilization and rectification measures on the right bank of the 1,200 MW P I project.
This development marks a crucial step forward in resolving long-standing technical issues that have delayed progress on the mega project. With the design agreement in place, the matter will now be reviewed by the Technical Coordination Committee (TCC). Once the TCC examines and endorses the revised designs, it will forward them to the project authority for final approval.
The approval will pave the way for rectification work to begin, alongside the long-awaited construction of the dam. If all goes according to plan, construction is expected to resume later this year, with the project aimed for completion by 2029 or 2030.
There was a technical-level bilateral meeting held in Delhi on 22nd April 2025, where the project’s designer, Central Water Commission (CWC), prepared a comprehensive report that included the proposed stabilization works along with additional measures suggested by RGoB.
The report was submitted on 2nd June 2025, and is currently under review by Bhutanese technical teams. The findings and recommendations of this review will guide the next steps for the project.
As pointed out in earlier articles by this paper, Bhutanese engineers and geologists worked with P I project consultants, like CWC and Central Electricity Authority (CEA) to jointly discuss and jointly design the rectification measures on the right bank.
These discussions and design were in the final stages with a slight difference on the degree of slope stabilization of the right banks.
CWC and CEA were proposing a slope stabilization at 30 degrees angle while the Bhutanese side is proposing it at 26 degrees angle.
If 30 degrees is agreed to then the overburden to be removed will be lesser, and at 26 degrees the overburden to be removed will be a little more.
With CWC agreeing to the Bhutanese proposal of 26 degrees it means removing more overburden and slope cutting to ensure lesser load on the right bank.
The Ministry of Energy and Natural Resources (MoENR) said all major components of the Punatsangchu-I project, excluding the dam, are at an advanced stage of completion. This includes the headrace tunnel, powerhouse with electro-mechanical equipment erection, and transmission lines.
Work on the dam remains pending due to ongoing efforts to stabilize the right bank hill slope.
It said the Governments of Bhutan and India are working closely to identify long-term stabilization measures to ensure the safety of the dam and related infrastructure.
MoENR stated that hydropower projects are inherently complex due to site specific geological and technical conditions that require customized engineering and design approaches. A key lesson from past experience is the importance of investing in detailed site investigations, particularly subsurface assessments.
The ministry also stated that most of the large-scale hydropower projects planned under Bhutan’s 20,000 MW by 2040 initiative already have Detailed Project Reports completed or in advanced stages. Improved accessibility to project sites has reduced logistical challenges compared to the past. However, subsurface investigations and environmental and social impact assessments remain time-intensive and must be approached carefully, as required by financing agencies and development partners during due diligence and project structuring.
To mitigate risks in upcoming projects, the government is adopting emerging technologies and bringing in experienced technical experts to carry out in-depth technical and financial due diligence. MoENR does not anticipate major changes in project locations or engineering designs. Feasibility studies for several new projects are currently underway, and are being conducted in strict accordance with Bhutan’s Hydropower Development Guidelines.
