Expert Panel Recommends Clearance for 1,605 MW Subansiri Upper Dam Despite 1,35,733 Trees Marked for Felling

The news

New Delhi. The Expert Appraisal Committee (EAC) of the Union Environment Ministry has recommended environmental clearance for the Subansiri Upper Hydroelectric Project (SUHEP), a run-of-the-river project on the Subansiri basin in Arunachal Pradesh, even as it expressed concern over the felling of a “substantial” number of trees, The Indian Express reports from the minutes of the EAC meeting. An environmental clearance is the Centre’s permission for a large project to proceed after its effects on air, water, land and people are studied. The final clearance will be subject to a Stage-1 forest clearance — an in-principle approval given by the Centre under the Forest Conservation Act — because the project requires the diversion of 2,733 hectares of forest land and the felling of approximately 1,35,733 trees. The EAC observed that the felling may affect forest structure, habitat continuity, biodiversity, wildlife movement and associated ecosystem services, and advised the project proponent, National Hydroelectric Power Corporation Limited (NHPC), to prepare a comprehensive, site-specific and time-bound Ecosystem Restoration and Biodiversity Management Plan. Compensatory afforestation — new planting to make up for forest lost — has been proposed across as many as 14 districts of Madhya Pradesh, on about 5,466 hectares of degraded forest land. Normally, an equivalent patch of non-forest land must be found locally, but since Arunachal Pradesh already has high forest cover, Ministry guidelines allow it to meet the obligation on non-forest land in lower-cover States; where no equivalent non-forest land is available, the Act requires a plantation twice the size of the diverted land on degraded land. The Indian Express had reported in February that until February 2026 Arunachal Pradesh had not complied with compensatory afforestation conditions for the Subansiri Lower project, also built by NHPC downstream, and the Ministry had sent six reminders. The standing committee of the National Board for Wildlife had cleared Subansiri Lower on condition that no upstream projects would follow, but the Supreme Court modified this on Arunachal Pradesh’s plea; its August 2009 directive says any upstream proposal “would be considered independently on its own merit by the Standing Committee”. The EAC noted assessments of glacial lake outburst flood discharge, peak flood discharge and dam-breach impacts on Subansiri Lower. Power generation and flood moderation are the stated objectives of the 1,605 MW plant near Menga, which envisages a 237 m-high storage dam. The syllabus link is GS3 on infrastructure, conservation and environmental impact assessment.

Static syllabus linkage

1. The EIA Notification, 2006 sends large hydropower projects to the Centre’s Expert Appraisal Committee. The Environment Impact Assessment Notification, 2006, issued under the Environment (Protection) Act, 1986, classifies projects into Category A, appraised by the Centre, and Category B, appraised by State-level authorities. River valley projects with hydroelectric capacity of 50 MW or more fall in Category A and are examined by a sectoral Expert Appraisal Committee, which recommends grant or rejection to the Ministry. The process runs through four stages: screening, scoping (fixing the terms of reference for the study), public consultation and appraisal. The EAC’s recommendation is advisory; the clearance itself is issued by the Ministry, often with conditions.
2. Forest clearance is a separate, two-stage approval under the 1980 forest law. Section 2 of the Forest (Conservation) Act, 1980 requires the Central Government’s prior approval before forest land is used for any non-forest purpose. In practice approval comes in two stages: Stage-1 is in-principle approval with conditions such as compensatory afforestation and payment of the net present value of the forest, and Stage-2 is final approval once those conditions are met. The 2023 amendment renamed the law the Van (Sanrakshan Evam Samvardhan) Adhiniyam, 1980, and exempted certain categories such as strategic linear projects within 100 km of international borders. The amendment’s narrowing of which land counts as ‘forest’ has been challenged before the Supreme Court.
3. Compensatory afforestation money is held in statutory funds. The Compensatory Afforestation Fund Act, 2016 created a National Compensatory Afforestation Fund and a State fund for each State in the public accounts, into which user agencies deposit money for compensatory afforestation and the net present value of diverted forest. Most of the money collected for a State goes to that State’s fund, with a smaller share to the National Fund, and it is administered by authorities known as CAMPA. The general rule is afforestation on equal non-forest land, or on degraded forest land of twice the area where non-forest land is not available. Critics have long argued that a young plantation elsewhere cannot replace the ecological functions of an old, contiguous natural forest.
4. The Subansiri is the Brahmaputra’s largest tributary and runs through a seismically active, glaciated basin. The Subansiri rises in the Tibetan Himalaya, flows through Arunachal Pradesh and joins the Brahmaputra in Assam, and is its largest tributary by discharge. The region lies in the highest seismic zone and has many glacial lakes, which is why glacial lake outburst floods (GLOFs) — sudden releases of water when a moraine or ice dam holding a glacial lake gives way — are now part of dam appraisal. The October 2023 GLOF from South Lhonak lake in Sikkim destroyed the Chungthang dam of the Teesta-III project, showing how a single event can cascade down a river with several dams. Run-of-the-river projects use the river’s flow with limited storage, whereas storage dams hold large volumes behind high walls.

Why UPSC loves this

1. GS3 pairs infrastructure with environmental impact assessment. The syllabus lists infrastructure (energy) alongside conservation and EIA. Mains questions have asked about the EIA process’s weaknesses, the environmental costs of Himalayan hydropower, and disasters such as the Chamoli and Sikkim floods. A single project with numbers for forest area, trees and afforestation lets a candidate make those arguments concretely.
2. Prelims tests the institutions in the clearance chain. UPSC has asked about the National Board for Wildlife, the CAMPA framework, and which projects need Central environmental clearance. The EAC, Stage-1 and Stage-2 forest approvals and the rule of twice the area on degraded land are all direct statement material.
3. The Northeast’s hydropower is also a strategic and water-security question. China’s dam building on the Yarlung Tsangpo upstream has led India to push projects in Arunachal Pradesh for power and as a buffer, as seen in the Siang Upper project carded on September 24. Questions on India–China relations and water security in the Brahmaputra basin can draw on the Subansiri projects as evidence.

Analysis

1. Planting in Madhya Pradesh to replace a forest in Arunachal Pradesh compensates the national accounts, not the ecosystem. The EAC itself lists what the felling will damage: forest structure, habitat continuity, wildlife movement and ecosystem services in the Subansiri basin. A plantation on 5,466 hectares of degraded land in 14 districts of Madhya Pradesh restores none of these locally; it only restores a number in the national forest-cover tally. The rule allowing high-cover States to afforest elsewhere was a practical answer to land scarcity, but in a biodiversity hotspot it converts a local loss into a paper gain. The counter-view is that Arunachal genuinely lacks non-forest land and that a well-run plantation in central India still sequesters carbon, which is a real, if different, benefit.
2. The Subansiri Lower record is the best predictor of how Subansiri Upper’s conditions will be met. The Indian Express reports that compensatory afforestation conditions for the downstream project were still unmet in February 2026 after six reminders. A clearance regime that grants new approvals while earlier conditions remain unfulfilled signals that conditions are negotiable. The EAC’s demand for a time-bound Ecosystem Restoration and Biodiversity Management Plan is sensible, but its value depends on monitoring and penalties, which the clearance system has historically lacked. The Ministry could make compliance on the earlier project a precondition for Stage-2 approval of the new one.
3. A 237 m ‘run-of-the-river’ storage dam is a contradiction the appraisal should resolve. The report describes the project both as run-of-the-river and as envisaging a 237 m-high storage dam for flood moderation. Run-of-the-river projects are usually presented as low-impact because they store little water, but flood moderation requires storage, and storage changes downstream flows, sediment and fisheries. The distinction matters for Assam, where downstream communities opposed Subansiri Lower precisely over altered flows and dam safety. The appraisal should state plainly how much water the reservoir will hold and how releases will be managed in the lean season and in floods.
4. Project-by-project clearance cannot capture what a chain of dams does to a river. The Supreme Court’s 2009 direction to judge upstream proposals ‘on its own merit’ was meant to be fair to each project, but rivers do not work project by project. With Subansiri Lower downstream and more projects planned across the basin, the relevant question is the cumulative effect on flows, sediment, fish migration and flood risk. The EAC has taken a step by assessing dam-breach effects on Subansiri Lower and GLOF discharge, which is more than many appraisals do. A basin-wide carrying-capacity study, updated before each new dam, would make that step systematic rather than occasional.
5. The case for the dam is real and should be stated honestly. The Northeast has large untapped hydropower potential, hydropower is a firm, non-fossil source that can balance solar and wind, and a storage dam can moderate floods in Assam. There is also a strategic argument given China’s dam building upstream on the Yarlung Tsangpo. None of this makes 1,35,733 trees irrelevant; it means the trade-off should be made openly, with the costs to forests and downstream communities priced in and the benefits delivered, rather than hidden behind the language of compensation.

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