Power production resumes from Upper Tamakoshi after 88 days

By A Staff Reporter,Kathmandu, Dec. 26: Power production has partially resumed from the 456 MW Upper Tamakoshi Hydropower Project, the largest of the hydropower plants in operation in Nepal. 

With partial repairs to the structures damaged by the landslides caused by the incessant rains on September 27 and 28, electricity generation resumed on Tuesday at 7.40 pm after 88 days, according to the Nepal Electricity Authority (NEA). 

The electricity produced from the project is connected to the national transmission system. 

Currently, 120 MW of electricity has been generated by fully utilising the water flow available in the river.

Electricity production from the project was stopped from 7 pm on September 27 due to high water flow in the Tamakoshi River in the wake of incessant rains.

The landslide on September 28 damaged the control room building, the desander and the underground canal (culvert) that carries water from the dam to the desander.

The road was blocked by large rocks on the approximately 300-metre access road from the power plant situated in Gongar to the dam situated in Lamabagar. 

The rocks were broken up using explosives to open the road. 

Tower No. 46 at Singati of the Gongar-Khimti 220 kV transmission line, which transmits electricity generated from the power plant, was damaged due to rains.

The left desander, out of the two desanders, has been partially repaired and production has started a day ahead of schedule for electricity generation, said NEA.

The old slope of the partially damaged desander wall has been demolished and repaired. 

Similarly, the cracks in the walls and ceilings of the culvert have been repaired by grouting.

The desander damaged by the landslide has been partially repaired and the Upper Tamakoshi has been brought into operation as a run-of-the-river for the time being. The remaining maintenance of the desander is underway, it said. 

Once the work is completed, the plant can be operated at full capacity for four hours during peak hours in the morning and evening when electricity demand is high, by storing water during times of low demand. 

The maintenance work is being carried out so that the plant can be operated during peak hours within mid-January 2025.

On December 3, a team of NEA, including Managing Director of NEA and chairman of Board of Directors of Upper Tamakoshi Hydropower Ltd. Kul Man Ghising had conducted an on-site inspection and set a schedule to complete the maintenance and start power generation by December 25.

Ghising said that due to the continuous efforts and day and night work of the company's board of directors, management, consultants and contractors, the maintenance of the Upper Tamakoshi was completed and electricity production was started a day ahead of the schedule. 

"The descender was filled with stones and mud, two company employees and two soldiers deployed for security lost their lives in the landslide, so there was panic among the employees deployed there, there was no access road to the site, and the electricity supply was cut off. 

In such a situation, it was very challenging to carry out the maintenance. We have managed to overcome this challenge with the support and cooperation of everyone and complete the maintenance and partially generate electricity," he said. 

"The closure of the country's largest power plant created difficulties in managing electricity supply. 

With the partial start of electricity production from the plant, electricity import from India will be balanced and electricity supply will be eased during the peak hours."

CEO of Upper Tamakoshi Hydropower Company Mohan Prasad Gautam said that the work was carried out according to the action plan, incorporating the suggestions received from the company's board of directors and expert group for operating the power plant, and the maintenance measures were adopted. 

With its regular follow-up, it was possible to generate electricity before the specified date, he said. 

He said that a tender has been called for the selection of a construction contractor to complete the repair of the other desander on the right before the start of the upcoming rainy season.

As the entire structure of the hydropower plant is insured, the maintenance costs of the damaged structure will be recovered from the amount received from the insurance. 

The company had claimed a preliminary insurance of Rs 1.78 billion for the damage caused by the landslide. 

The company and insurer - National Insurance Company - are currently jointly assessing the damage. The insurance amount will be paid after the work is completed. 

Similarly, three months of income from electricity sales has been insured. The company will receive two months of income as per the terms and conditions mentioned in the insurance agreement.