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Construction of the 99.8 MW Tamakoshi-5 Hydropower Project in Dolakha has gathered pace, with tunnel excavation now being carried out simultaneously from five different locations to accelerate the development of its main underground structures.

According to the project’s annual progress report for fiscal year 2025/26 (FY 2082/83), a total of 784 meters of the Headrace Tunnel (HRT) was excavated during the reporting period.

The report, published by Tamakoshi Hydropower Company Limited, states that excavation has been completed for the headpond, spillway, Main Access Tunnel (MAT), Cable and Ventilation Tunnel (CVT), transformer cavern, powerhouse adit tunnel, bus duct gallery, emergency escape tunnel, upstream manifold, Adit-2, Adit-3, and other connecting tunnels.

Tamakoshi-5 Hydropower Project accelerates tunnel construction from five working faces

Kathmandu: Construction of the 99.8 MW Tamakoshi-5 Hydropower Project in Dolakha has gained momentum, with tunnel excavation now being carried out simultaneously from five working faces to accelerate the development of its main underground structures.

According to the project’s annual progress report for fiscal year 2025/26, the project excavated 784 meters of the Headrace Tunnel (HRT) during the reporting period, equivalent to approximately 9.67 percent of the tunnel’s total length.

The annual report, published by Tamakoshi Hydropower Company Limited, states that excavation has already been completed for the headpond, spillway, Main Access Tunnel (MAT), Cable and Ventilation Tunnel (CVT), transformer cavern, powerhouse adit tunnel, bus duct gallery, emergency escape tunnel, upstream manifold, Adit-2, Adit-3, and other connecting tunnels.

The company reported significant progress in the construction of the underground powerhouse. Excavation of the powerhouse cavern has reached 64.71 percent, with the first and second excavation levels completed and work on the third level currently underway. Excavation of the transformer cavern has also been completed.

The report further states that 273.3 meters of excavation was completed in the spillway tunnel during the fiscal year, achieving 98.4 percent of the annual target. Excavation has also reached 488.61 meters at Adit-2, 314 meters at Adit-3, and 404.2 meters at Adit-4, while 11,960 cubic meters of excavation has been completed in the headpond area.

The project, however, faced an eight-month delay due to pending approvals for the use of forest land and public land rights. Construction was suspended after a directive from the Gaurishankar Conservation Area, but resumed on March 8, 2026, after the Ministry of Forests and Environment granted the required approvals.

Following the resumption of construction, the project achieved an additional 2.68 percent physical progress within just four months. Overall cumulative physical progress has now reached 21.68 percent. Against an annual target of 14.89 percent, the project recorded 6.30 percent progress during the fiscal year.

The project is being implemented through three major contract packages. Under Lot-1, civil and hydro-mechanical works are progressing rapidly. Under Lot-2, contracts for electro-mechanical equipment and the transmission line have been mobilized, while Lot-3, covering the construction of the permanent camp, has been completed.

With an estimated project cost of approximately Rs 21.95 billion, the project’s overall financial progress has reached 25.90 percent. According to the company, Rs 5.69 billion has been spent so far, including Rs 2.99 billion during the reporting period alone.

Jalasarokar