Er.energyNP@Gmail.com

The 69-megawatt Marsyangdi Hydropower Station has resumed electricity generation after completing a comprehensive maintenance and repair program that required a full shutdown of the plant for 21 days.

Located in Aanbukhaireni Rural Municipality, the hydropower facility restarted operations following the successful completion of complex technical and civil engineering works aimed at strengthening key infrastructure and improving long-term operational reliability.

According to the Nepal Electricity Authority (NEA), the plant had been completely shut down to carry out large-scale maintenance and rehabilitation activities that had been pending for years. The works were completed within the scheduled timeframe, allowing electricity generation to resume without delay.

One of Nepal’s Largest Hydropower Stations

Among hydropower plants operated by NEA, the Marsyangdi facility ranks as the third largest in installed capacity and the second largest in annual electricity production.

During the last fiscal year 2081/82 BS (July 16, 2024 – July 15, 2025 AD), the plant generated 451.7 gigawatt hours (GWh) of electricity, making it a critical contributor to Nepal’s national power supply.

In the current fiscal year 2082/83 BS (July 16, 2025 – July 15, 2026 AD), the plant had already produced 293.5 GWh of electricity by the end of Magh 2082 BS (mid-February 2026 AD) before the maintenance shutdown was initiated.

To ensure sustainable long-term operation, the plant was taken offline beginning Falgun 2, 2082 BS (February 14, 2026 AD) to carry out major repair and rehabilitation works.

Major Structural Repairs Completed

Plant chief Kapildev Manjan said the shutdown period was used to complete several technically challenging works that had remained unresolved for years.

One of the most critical tasks involved strengthening civil structures near the dam area. The upper riverbank near the dam and sections around the desander structure had experienced erosion that posed potential risks to plant infrastructure.

Repair and reinforcement works were carried out to protect these structures and ensure long-term stability of the hydropower facility.

Under-Sluice Gate Restored After 14 Years

A major milestone of the maintenance program was the restoration of the under-sluice gate, a key hydraulic component designed to prevent sand and sediment from entering the water conveyance tunnel.

According to plant officials, the structure had remained non-functional for approximately 14 years due to structural damage.

Engineers successfully repaired the damaged components during the shutdown, making the system operational again. The restoration is expected to significantly reduce sediment intrusion into the tunnel system, which has historically posed a major operational challenge for Himalayan hydropower projects.

Sediment Removal and Mechanical Overhaul

Another important activity completed during the maintenance period was the removal of sand deposits that had accumulated for years in the compensating basin located near the main intake structure.

Excessive sediment accumulation can reduce water flow efficiency and affect turbine performance, making sediment management a critical maintenance priority for run-of-river hydropower plants like Marsyangdi.

Plant chief Manjan said several previously stalled contracts and mechanical repair tasks were also completed during the shutdown period.

“We prioritized long-pending contractual works and mechanical repairs to ensure the plant’s reliability,” he said.

Overhauling of Unit No. 3

Technicians also conducted a full overhaul of generating Unit No. 3, one of the plant’s key turbine-generator units.

The maintenance work was carried out by in-house engineers and technicians from the Marsyangdi plant along with technical staff mobilized from other hydropower stations under NEA.

This collaborative technical approach allowed the utility to complete the overhaul efficiently while minimizing operational costs.

Round-the-Clock Civil Works at Dam Site

Civil engineering works at the dam site were carried out under a 24-hour work schedule, with labor teams deployed in three shifts to ensure timely completion of the repairs.

According to plant management, the shutdown was strategically scheduled during a period when river discharge levels were at their lowest, minimizing the impact on electricity generation and the national power supply.

“We planned the maintenance work during a period of minimal river flow so that the reduction in electricity production would be limited,” Manjan explained.

Coordinated Effort Across NEA Departments

Officials credited the successful completion of the project to strong coordination among NEA’s central offices, departmental units, and regional directorates.

Support from senior management allowed engineers to address several critical civil works that had remained pending for years due to technical complexity and logistical challenges.

Electrical System Upgrades

In addition to structural and mechanical repairs, the maintenance program also included electrical upgrades within the powerhouse.

Among the works completed was the replacement of LT-type breakers, along with other necessary electrical and mechanical maintenance tasks designed to improve operational safety and reliability.

Plant officials said the completed maintenance and upgrades are expected to enhance electricity generation efficiency while reducing technical risks associated with aging infrastructure.

Importance for Nepal’s Hydropower Sector

The Marsyangdi Hydropower Station is one of Nepal’s most strategically important state-owned hydropower plants, playing a vital role in stabilizing the country’s electricity supply, particularly during the dry season.

With hydropower accounting for the overwhelming majority of Nepal’s electricity generation, ensuring the reliability of major plants like Marsyangdi is essential for maintaining grid stability and meeting growing national energy demand.

The successful completion of the 21-day maintenance shutdown is expected to strengthen the plant’s operational performance and extend the lifespan of critical infrastructure within one of Nepal’s key hydropower assets.