A maintenance schedule has been established to resume electricity generation from the 456 MW Upper Tamakoshi hydropower project, the largest among operational hydropower projects, by December 25th.

A landslide triggered by incessant rains on September 27th and 28th caused significant damage to the dam area structures, including the headworks of the Upper Tamakoshi hydropower station, located in Bigu Rural Municipality-1, Lamabagar, Dolakha. The landslide severely impacted several components, including the control room building, the sand settling basin (desander), and the underground culvert that channels water from the dam to the desander, all located slightly downstream of the dam site.

Of the two desanders, maintenance on the left-side desander was completed by December 25th, setting the stage for electricity generation to resume. This involved demolishing and repairing the partially damaged slope of the desander wall and carrying out grouting to address cracks in the walls and ceiling of the culvert.

The right-side desander is planned for repairs, and the surface-level control room will be relocated underground. This work is scheduled to be completed before the onset of the next rainy season. Additionally, repairs to one of the project’s transmission line towers damaged by rain have been completed.

The Upper Tamakoshi Hydropower Ltd., the project’s promoter company, is actively overseeing the restoration work. On Wednesday, a team led by Kulman Ghising, Executive Director of Nepal Electricity Authority (NEA) and Chairman of the Board of Directors, along with board members and the company’s Chief Executive Officer (CEO), conducted an on-site inspection to monitor the progress of the ongoing maintenance efforts.

The team engaged with project management, consultants, and construction professionals to expedite power generation. The goal is to commence electricity generation within 10 days and complete all remaining maintenance within 15 days after that. The project is expected to operate at full capacity for up to 4 hours during peak demand by storing water during periods of low electricity demand.

Failure to resume operations during the winter would create challenges in balancing electricity demand and supply, prompting the board of directors to prioritize measures to restart the plant as soon as possible.

Executive Director Ghising emphasized the urgency of the situation, stating, “It will be a difficult situation if electricity from Upper Tamakoshi is not produced on schedule. Until next March, we only have permission to import electricity from India during the day and night, but not during peak hours in the morning and evening. This constraint, combined with the domestic production shortfall, would lead to critical issues in managing electricity demand.”

He further urged all stakeholders to approach the maintenance with seriousness and sensitivity to meet the specified deadlines.

Power generation at the plant was halted on September 23rd at 7 PM due to high water flow in the Tamakoshi River, necessitating the opening of all dam gates to prevent further structural damage. Mohan Prasad Gautam, CEO of Upper Tamakoshi Hydropower Ltd., assured that all possible measures are being implemented to adhere to the maintenance schedule and resume power generation promptly.

Source: Kantipur