NHPC aims to begin electricity generation from the 2000 MW Lower Subansiri Hydroelectric Project (LSHP) by May-end. Target is filling the reservoir by April and commissioning 750-1000 MW by May end.
This plan has triggered downstream impact worries in Assam. The All Assam Students’ Union (AASU) has voiced concerns.
Key worry is the absence of an independent reservoir management authority (SIIRMA). Recommended by an Environment Ministry-constituted panel.
SIIRMA was meant to monitor reservoir levels and minimize downstream risks. Especially during panic water releases/floods.
Expert panel recommended SIIRMA should be set up before filling the reservoir. A continuous release of minimum 240 cumec water downstream was suggested.
Expert Panel suggested discharge release should not worsen Majuli Island erosion. Concerns relate to erosion of Majuli Island.
NHPC, Centre, Assam, and Arunachal Pradesh accepted SIIRMA recommendation in 2019. Yet, it hasn’t been implemented.
Wildlife Institute of India (WII) report raised concerns about elephants. Specifically, the risk of elephants being washed away during “panic release” of water.
The project, located on the Subansiri River (Arunachal Pradesh/Assam border), was delayed due to protests (2011-2019). Work was suspended, but cleared by NGT in 2019.
LSHP reservoir details: 33.5 sq. km. surface area, 1.37 cubic km. gross storage capacity.