- India’s second-largest hydroelectric project, SLHEP (2000 MW), is nearing partial commissioning.
- Three units (750 MW) to be commissioned by May 2025, full completion by March 2026.
Location: Gerukamukh, along the Assam–Arunachal Pradesh border.
Project Timeline and Challenges
- Construction began: January 2005.
- Opposition by All Assam Students’ Union (AASU) over downstream impacts.
- Work halted in December 2011 after 50% progress due to geological and seismic concerns.
Expert Interventions
- 2011: Assam Expert Group recommends halt citing seismic risks.
- 2012: Planning Commission’s technical committee (CD Thatte, MS Reddy) clears hydrology.
- 2013: Dam Design Review Panel (DDRP) suggests:
- Increase dam width: 171m → 271m
- Cutoff walls (upstream & downstream)
- Grouting, rock anchors, and cable tendons
- 2014: CWC recommends 240 cum/sec environmental flow for biodiversity.
Project Oversight and Legal Scrutiny
- 2015: GoI forms Project Oversight Committee (POC).
- Opposed reduction in dam height due to PMF (Probable Maximum Flood).
- Committed to:
- Continuous turbine operation to maintain flow
- Independent reservoir authority
- 67 km of downstream protection
- Development schemes worth ₹658 crore
- 2017: NGT involved; GoI forms 3-member expert committee
- 2019: Final NGT verdict:
- All key concerns addressed
- Construction resumes after 8-year pause
Flood Forecasting & Early Warning Systems
- Flood forecasting by CWC & IMD since 2017
- EWS infrastructure:
- AWL recorders with GSM telemetry at Tamen and Daporijo
- 6-hour lead time
- 24×7 monitoring from Faridabad control room
- Includes:
- Reservoir Operation Manual
- Disaster Management Plan
- SOP for emergency water releases
Power Allocation
- Total Capacity: 2,000 MW
- Arunachal Pradesh: 240 MW free + 34 MW purchase
- Assam: 25 MW free + 208 MW purchase + 300 MW additional due to anti-dam agitation
SLHEP exemplifies how technical expertise, legal oversight, and environmental safeguards can enable sustainable infrastructure. Once completed, it will significantly boost renewable energy, especially in the Northeast.
