The 275 MW Kopili Hydropower Dam of NEEPCO (a Union Power Ministry organisation, now under NTPC) has again faced a major disaster on Saturday, March 26, 2022. Earlier, the same project had suffered disaster in October 2019.[i]
The penstock pipe that takes water at high flow rates and speed from the Umrangso dam to the hydropower house burst during early hours of Saturday in Assam’s Dima Hasao (earlier called North Cachar Hill) district. A large portion of the Kopili Hydro Electric Plant was also inundated.[ii] At least three employees of the North Eastern Electric Power Corporation Limited (NEEPCO) who were present at the site were killed in the mishap.
Of the three dead, two were reported to be residents of Assam’s Jorhat and Tinsukia District while one was from Dima Hasao District. The deceased have been identified as Dimaraj Jahari (30 year old), a contractual employee, Anupam Saikia, the Deputy Manager (Civil, 35 year old), and Jayanta Hazarika (59 yrs old, he died on the way to hospital), the manager (Civil) of the project.[iii] According to one report, they perished while trying to close the intake gate as the water overflowed from the reservoir.[iv] According to another report of NE Live[v], the intake gate was under repair. According to a spokesman speaking at the plant there is shut down in the machines since 4 months.
According to Dima Hasao Deputy Commissioner, NDRF and SDRF teams are on standby and senior officials have been stationed at the site and drone surveillance has also been started. The mishap occurred due to heavy rainfall in the upstream Meghalaya, it is suggested by the NEECO spokesman, but it is not clear what disaster management measures were taken to prevent such a disaster. The DC said that the Surge Shaft overflowed and the Khandong Power House got submerged. When the employees were moving towards the surge shaft, trees fell on and around them, in which the employees got killed. This description, however, does not match with the use of word explosion and burst of pipeline in a number of news reports. The Times of India, though reported the version suggested by the DC.[vi]
According to another report, the explosion at 11.30 am occurred due to blockade created by stones and fallen trees. “Their bodies were found more than two hours later,” an official said requesting anonymity.[vii]
Another report said: “A large portion of a powerhouse of Kopili hydroelectric project of NEEPCO at Umrangso in Assam`s Dima Hasao was damaged due to sudden rising of water level in the Kopili river.”[viii]
This report provides more detailed narrative: “At around 10:45 am on 26.03.2022, temporary barrier constructed at Intake Weir in Khandong System at Kopili HEP was breached by suddenly raised Kopili reservoir. The water gushed into the Head Race Tunnel and thereafter entered into both the Power Houses connected to Khandong system. Both the power houses were under shutdown condition due to repairing works in Intake and HRT since 11th Jan’2022. The workmen and the engineers engaged in the repairing works were quickly evacuated. The process of lowering of Intake Gate was started immediately at around 11:00 am. Reservoir water kept on rising rapidly with attainment of level of EL. 709.0 m at around 02:00 pm. This raising is due to unprecedented and untimely rainfall in the catchment area. Team of NEEPCO engineer and staff was deputed to oversee the process of lowering of surge shaft gate. While going to the surge shaft area, a big tree got uprooted and fell on the members of the team at around 01:40 pm in the vicinity of surge shaft. Two engineers and one workman got crushed in the accident. Anupam Saikia, Dy. M (C) and Demiraj Johari, Contract Labour died on the spot itself. Jayanta Hazarika, Manager (C) who was severely injured in the accident and brought to the primary health center of the project succumbed to his injuries at around 3:15 pm.”
According to India Meteorology Department’s daily district wise rainfall data for the 24 hrs ending at 0800 hrs on March 26, 2022, the N C Hills district of Assam received 96.4 mm rainfall and East Khasi Hills district of Meghalaya received 97.6 mm rainfall, though the Jaintia Hills district of Assam nearby received much lower 38.6 mm rainfall. There is no doubt that these are all very high rainfalls in this season, but the dam authorities are supposed to be able to manage such rainfalls in these areas.
NEEPCO hydro projects have seen a number of such mishaps. Besides the two mishaps at the Kopili project, there have been cases of sudden release of water from NEEPCO’s Doyang and Ranganadi hydropower project and a number of issues have also been known to affect at NEEPCO’s Kameng hydropower project. In absence of any credible independent enquiry into such incidents followed by fixing the accountability and learning lessons for future, the incidents are only likely to increase in frequency and intensity. The Dam Safety Act passed by the parliament is not helpful in preventing such incidents.
[i] https://sandrp.in/2019/10/08/major-disaster-at-kopili-dam-of-neepco-in-assam/, a video of the disaster can be seen here: https://www.youtube.com/watch?v=PEZuFujYJ1M