Flooding in the Bhotekoshi-Trishuli river systems has caused catastrophic damage to hydropower projects in Rasuwa and Nuwakot, with the government’s preliminary assessment putting losses to the hydropower sector alone at more than Rs 80bn.
The assessment, carried out by the Ministry of Energy, Water Resources and Irrigation, covers 12 hydropower projects that were either operational or under construction. It does not include damage to transmission and distribution infrastructure, for which assessment is still underway.
The flooding on Aug 26 also affected irrigation systems, solar power and alternative energy infrastructure in the two districts. The government has yet to determine the final extent of the damage.
The human toll remains equally alarming. Hundreds of workers and technical staff remain missing or out of contact after being trapped by floodwaters and debris, particularly inside underground powerhouses, headworks and access tunnels.
The Ministry’s preliminary assessment puts the number of workers, technical staff and local people missing or trapped at 983 across the affected sites. A separate update issued by the Independent Power Producers’ Association, Nepal (IPPAN), however, puts the number of people out of contact at 947 across 11 projects. The figures are preliminary and have continued to change as rescue and communication efforts progress.
Of the 12 projects, eight were operational, with a combined capacity of 281 MW, while four projects with a combined capacity of 388 MW were under construction. Together, the projects represent 669 MW of installed or planned capacity.
The immediate challenge for the hydropower sector is not only the physical destruction of infrastructure but also the ongoing rescue operation. Many of the affected facilities are located in steep mountain terrain and rely on underground tunnels and powerhouses. Floodwaters have filled these structures with mud, rocks and debris, while continuing rainfall and swollen rivers have made it difficult for rescue teams and heavy machinery to reach them.
Rasuwa bears the brunt
Rasuwa has suffered the heaviest impact, with six major hydropower facilities affected, including some of the country’s largest projects.
The affected projects in the district have a combined capacity of 494 MW, according to the preliminary assessment. They include Upper Trishuli-1, Rasuwagadhi, Rasuwa-Bhotekoshi, Langtang Khola, Chilime and Mailung Khola.
The 216-MW Upper Trishuli-1, which is under construction, has recorded the largest number of people missing. According to IPPAN, 557 people associated with the project remain missing or out of contact. The project had 1,433 people at the site, of whom 876 have been rescued. Around 115 people are suspected to be trapped in the headworks and main tunnel. Those reported out of contact include 15 people from NWEDC, seven from JH Consult, 56 from Doosan, 385 from PowerChina and 94 from Andritz Hydro. A 44-member South Korean rescue team has also arrived to assist in the search. Nine Korean nationals are among those reported missing.
The 111-MW Rasuwagadhi Hydropower Project, which is operational, has reported 93 people out of contact. It remains uncertain how many of them may be trapped inside the underground powerhouse. Three people managed to reach a safe location, while four others reportedly rescued themselves from underground two days after the disaster. Rescue operations at Rasuwagadhi have been complicated by the rising river. An excavator could not be deployed because of rising water levels and erosion, while a protection wall was damaged. A helicopter also could not land at the site.
The 120-MW Rasuwa-Bhotekoshi project, which is under construction, has reported four people missing. The IPPAN update also records the rescue of three Chinese and two Nepali workers by helicopter. The figures do not fully correspond, however, with the reported number of missing people.
At the 20-MW Langtang Khola project, which was in testing and commissioning, 41 people were reported missing or out of contact, while 19 were rescued. Search teams had advanced around 150 metres into the tunnel. The Ministry’s preliminary account says workers may have been trapped in an access tunnel while concreting work was being carried out around the penstock.
The 22-MW Chilime Hydropower Project has also been hit hard. IPPAN reported six people trapped inside the underground powerhouse, while 71 people were at the site and others had reached safety. The Ministry’s preliminary account, however, puts the number of missing people at eight, indicating that the human toll remains subject to verification.
Rescue operations have been particularly difficult because of continued rainfall and rising river levels. Nepali Army personnel and an expert team from the Indian Army have been deployed, but rescuers have so far been unable to reach those trapped underground. Machinery is being prepared for the operation, although an excavator had not yet reached the site at the time of the IPPAN update.
At the 5-MW Mailung Khola Hydropower Project, seven people remain out of contact, with some having been unreachable for as long as a week.
Nuwakot projects severely affected
Six hydropower and energy facilities in Nuwakot have been affected, with a combined capacity of 175.7 MW. The preliminary assessment puts the number of people missing from these sites at 237.
The 37-MW Upper Trishuli-3B, which is under construction, accounts for the largest number of missing people in Nuwakot. According to IPPAN, 191 people are out of contact. They include 141 workers from Fewa Construction, 21 from Trishuli Hydropower, seven family members of employees, 12 workers from Cheska Engineering, one security guard and three Kathmandu University interns. Twenty-three tunnel workers managed to escape, but heavy mud and debris blocked safe access to other workers. Two excavators had been sent to the site, with preparations underway to deploy three. The Ministry’s preliminary account says five bodies have been recovered from the Upper Trishuli-3B site. This figure was not included in the corresponding IPPAN project update.
The 60-MW Upper Trishuli-3A, which is operational, has 42 people believed to be trapped inside its underground powerhouse. The workers were carrying out maintenance work when the flood struck. The tunnel leading to the powerhouse has been blocked by rocks, sand and mud, while the Trishuli River has remained dangerously high. The Nepal Electricity Authority has been working to create an alternative access route, including blasting large rocks and pumping out water, to reach the workers trapped underground.
At the 24-MW Trishuli Hydropower Center, three people are missing—two security guards and one employee. IPPAN says 70 of the 73 people at the site are safe. At the 14.1-MW Devighat Hydropower Project, one security guard is reported missing. The 15.6-MW Middle Trishuli Ganga Hydropower Project, which is under construction, has reported two people missing, while one injured person has been rescued.
Solar plant among damaged energy infrastructure
The flooding also damaged the Nuwakot Solar Power Project. The preliminary assessment describes the project as a 25-MW solar facility, with no casualties reported. The IPPAN update, however, provides a more detailed assessment, saying a 19.6-MW plant was completely damaged, with four of its seven sites swept away. Office and control buildings were also destroyed, although all personnel were reported safe. The project was built by a Chinese company and was scheduled to be handed over to the Nepal Electricity Authority after five years. The flood damaged the facility before the handover could take place.
