Guwahati, Aug 10: The Union Power Ministry has listed six major hydropower projects in Northeast India as “vulnerable,” including the under-construction 2,000 MW Lower Subansiri project on the Assam- Arunachal Pradesh border.
The Central Electricity Authority (CEA) categorised these projects as vulnerable based on their location above 1,500 metres and position as the first in the river basin in the upper Himalayan reaches — conditions that heighten risks from flash floods, landslides, and other climate-induced hazards.
The information was provided by Minister of State in the Power Ministry, Shripad Naik, in Parliament.
The projects flagged in the Northeast are: Lower Subansiri (2,000 MW) — Arunachal Pradesh (under construction)
Panyor Lower (405 MW) — Arunachal Pradesh (commissioned), Kameng (600 MW) — Arunachal Pradesh (commissioned)
, Rangit (60 MW) — Sikkim (commissioned), Chuzachen (110 MW) — Sikkim (commissioned) and Tashiding (97 MW) — Sikkim (commissioned)
The Lower Subansiri project has been under construction for over two decades, delayed by technical, environmental, and safety concerns. Its classification as “vulnerable” by the Central Electricity Authority stems from its location above 1,500 metres in the upper reaches of the Himalayan basin, making Early Warning Systems mandatory.
Civil works on the dam and all eight headrace tunnels are complete, with roofing and powerhouse works finished up to Unit 7. Heavy mechanical works are fully done, while electrical and mechanical commissioning are in an advanced stage. Units 1–3 have completed dry commissioning, with the first three units expected online by August–September 2025. The National Dam Safety Authority inspected the dam in April 2025, raising observations to which NHPC has responded, with balance works targeted for completion by July 2025.
The project cost has risen by Rs 6285.33 crores to Rs 26075.54 crores. The anticipated date of commissioning is May 2026.
Once operational, Lower Subansiri is set to supply over 7,500 million units of electricity annually, but experts caution that its success will hinge on robust disaster risk management in a climate-sensitive zone.
The Hydro Electric Projects(HEPs), which are located generally above meters elevation of 1500 meters and which are first in the basin in the upper reaches of the Himalayan region, have been identified as vulnerable by the Central Electricity Authority (CEA). For such HEPs, it is mandatory to implement the Early Warning System (EWS). An advisory has also been issued by CEA to all the developers of identified vulnerable projects for implementing EWS in these projects,” Naik stated in his reply.
