Context:
The Arunachal Pradesh government has yet to comply with compensatory afforestation requirements for the Subansiri Lower Hydroelectric Project, raising environmental concerns regarding forest loss and wildlife corridors.
Key Highlights:
Project Overview – Subansiri Lower Hydel Project
• Installed capacity: 2000 MW.
• Located on the Subansiri River, a major tributary of the Brahmaputra.
• Developed by National Hydroelectric Power Corporation (NHPC).
• First unit commissioned in December 2023, after a 21-year delay since forest clearance in 2004.
Compensatory Afforestation Requirement
• The Environment Ministry mandated compensatory afforestation on 31.83 sq km of land.
• Arunachal Pradesh has not implemented this requirement despite six reminders from the Centre.
• The Ministry has requested details including:
• Identification of afforestation sites
• Geo-coordinates of land parcels
• Implementation status of plantation activities.
Environmental and Wildlife Concerns
Hydro-peaking Impacts
• Hydro-peaking refers to sudden release of water from dams during peak electricity demand.
• According to the Wildlife Institute of India (WII):
• Rapid water level changes could create flash flood-like conditions downstream.
• May damage riverine vegetation and habitat stability.
Impact on Elephant Corridors
• The Subansiri River region forms an important east–west elephant corridor.
• Hydro-peaking may disrupt elephant movement, affecting:
• Migration patterns
• Habitat connectivity
• Genetic diversity of elephant populations.
- The Standing Committee of the National Board for Wildlife (NBWL) emphasized avoiding water release during elephant crossings.
Project Delays and Local Resistance
• Construction faced major stoppage between 2011 and 2019 due to:
• Local protests in Assam.
• Concerns over dam safety, ecological impact, and downstream flooding.
• Legal challenges in courts.
Forest Clearance and Tree Felling
• Clear felling of trees in the project’s submergence area began in October 2021.
• Completed by September 2023.
Relevant Prelims Points:
• Compensatory Afforestation (CA)
• Mandatory under the Forest (Conservation) Act, 1980.
• Requires plantation of equivalent or larger forest area when forest land is diverted for non-forest use.
• Implemented through the Compensatory Afforestation Fund Management and Planning Authority (CAMPA).
- Hydro-peaking
• Practice of releasing water from reservoirs during peak electricity demand hours.
• Causes rapid fluctuations in downstream river levels. - Elephant Corridors
• Linear habitat links enabling elephant movement between forests.
• Crucial for gene flow, population viability, and reducing human–elephant conflict. - Subansiri River
• Largest tributary of the Brahmaputra.
• Originates in Tibet and flows through Arunachal Pradesh and Assam.
Relevant Mains Points:
Hydropower Development vs Environmental Conservation
• Large hydropower projects contribute to:
• Renewable energy generation
• Energy security and regional development.
• However, they also raise concerns regarding:
• Deforestation and biodiversity loss
• Alteration of river ecosystems
• Displacement of communities.
Wildlife Corridor Protection
• Infrastructure projects may fragment critical wildlife corridors.
• Disruption of corridors increases:
• Human-wildlife conflict
• Genetic isolation of animal populations.
Governance Challenges in Environmental Compliance
• Delayed implementation of compensatory afforestation reflects:
• Weak monitoring mechanisms.
• Coordination gaps between central and state authorities.
• Institutional capacity constraints.
Way Forward
• Ensure strict compliance with compensatory afforestation requirements.
• Conduct comprehensive ecological impact assessments for hydro-peaking effects.
• Implement wildlife-sensitive dam operation protocols.
• Strengthen monitoring through CAMPA and NBWL oversight.
• Balance renewable energy expansion with biodiversity conservation.
UPSC Relevance:
• Prelims: Compensatory afforestation, CAMPA, hydro-peaking, Subansiri River.
• Mains: GS Paper III – Environmental Impact of Infrastructure Projects, Hydropower Development, Wildlife Conservation and Habitat Connectivity.