Dam Safety in India: IIT Madras Study Highlights Need for Site-Specific Seismic Risk Assessment and Stronger Dam Governance

Recent Developments: IIT Madras Study and Seismic Risk

• A 2026 IIT Madras study developed a national-scale Probabilistic Seismic Hazard Analysis (PSHA) framework covering 6,545 operational dams listed in the National Register of Specified Dams, 2025, highlighting the limitations of conventional seismic zonation for assessing risks to large dams.
• The study used regional seismic-source models, ground-motion models and a logic-tree framework to generate site-specific seismic hazard estimates and uniform hazard response spectra for different return periods.
• Its PSHA-based approach enables dam sites to be prioritised according to seismic hazard potential and supports more detailed seismic evaluation of dams located in earthquake-prone regions.
• The study is significant because many existing dams were designed using earlier deterministic approaches that may not adequately incorporate updated seismo-tectonic information, ground-motion characteristics and site-specific effects.
• The study also developed PSHA_India_IITM, a graphical tool for site-specific seismic hazard assessment, uniform hazard response spectra generation and selection and scaling of ground motions.

India’s Dam Landscape and Emerging Safety Risks:

Scale and Ageing Infrastructure:

• India ranks third globally in terms of large dams, after China and the United States; the 2025 inventory records 6,628 specified dams, comprising 6,545 operational dams and 83 under construction.
• Maharashtra has the largest number of specified dams, followed by Madhya Pradesh, Gujarat, Chhattisgarh, Rajasthan, Karnataka and Odisha.
• More than 26% of specified dams are over 50 years old, increasing the importance of rehabilitation, instrumentation, periodic safety evaluation and adequate maintenance.
• India’s dam heritage extends to Kallanai or Grand Anicut in Tamil Nadu, constructed in the 2nd century CE and still functioning as a major hydraulic structure.

Major Causes of Dam Failure:

• Poor maintenance: Deferred repairs, deterioration and inadequate operation and maintenance can weaken structural and hydraulic safety.
• Design deficiencies: Older dams may not fully reflect present-day hydrological, seismic or engineering knowledge, requiring reassessment against updated design standards.
• Extreme natural events: Earthquakes, extreme rainfall, floods and other hazards can impose stresses beyond the assumptions used during original design.
• Overtopping: Excessive inflows can exceed reservoir or spillway capacity, allowing water to flow over the dam and potentially cause erosion and breaching.
• Inadequate monitoring: Weak surveillance and insufficient instrumentation can delay detection of seepage, deformation, cracking or other distress.
• Sedimentation: Reservoir siltation reduces effective storage and can alter flood-management capacity, increasing operational and safety challenges.
• The Central Water Commission records breaching and overtopping among the major causes of historical dam failures in India, with breaching accounting for about 44% and overtopping about 25% of recorded cases in its cited dataset.

Why Dam Safety Is a Major Governance and Disaster-Management Concern:

Ageing and Structural Vulnerability:

• Age alone does not automatically make a dam unsafe; the quality of maintenance, structural integrity, safety instrumentation and operational practices determine its continuing safety.
• Many older dams face structural deficiencies, inadequate monitoring facilities and design assumptions that may not correspond to present hydrological and seismic conditions.
• Dam safety therefore requires a shift from one-time construction-based assessment towards life-cycle risk management involving surveillance, rehabilitation and periodic reassessment.

Downstream Risk and Disaster Management:

• Dam failure can produce sudden downstream flooding, affecting human settlements, agricultural land, roads, bridges, power infrastructure and other critical assets.
• The consequences are particularly severe where settlements and economic infrastructure have expanded downstream after dam construction.
• Effective dam safety therefore requires integration of structural safety, flood forecasting, early-warning systems, emergency action plans and downstream preparedness.

Dam Safety Act, 2021: Institutional Framework

National-Level Institutions:

• The Dam Safety Act, 2021, which came into force on 30 December 2021, provides a statutory framework for surveillance, inspection, operation and maintenance of specified dams and prevention of dam-failure-related disasters.
• The Act created a four-tier institutional architecture comprising the National Committee on Dam Safety, National Dam Safety Authority, State Committees on Dam Safety and State Dam Safety Organisations.
• The National Committee on Dam Safety functions as the policy-oriented body responsible for evolving dam-safety policies, maintaining standards and recommending necessary regulations.
• The National Dam Safety Authority functions as the national regulatory and implementing body for dam-safety policies and standards and can address issues between State Dam Safety Organisations and specified-dam owners.

State-Level Institutions and Dam Owners:

• States having specified dams are required to establish State Committees on Dam Safety and State Dam Safety Organisations; all 28 States and 3 Union Territories with specified dams had established the prescribed institutional structures.
• State Dam Safety Organisations undertake surveillance, inspection and monitoring, maintain dam-related information and recommend corrective measures.
• Dam owners are responsible for operation and maintenance, adequate funding for repairs, establishment of Dam Safety Units, regular inspections, preparation of Emergency Action Plans and periodic comprehensive safety evaluations.

Risk Assessment and Safety Evaluation:

• The regulations require specified dams to undergo risk assessment studies and comprehensive safety evaluations at prescribed intervals; the first comprehensive evaluation of existing specified dams is to be followed by evaluations at 10-year intervals, or earlier where directed.
• Dam owners must also undertake pre-monsoon and post-monsoon inspections and inspections following calamities or signs of distress.
• Post-monsoon inspection results are categorised according to the urgency of remedial action; for 2025, 3 specified dams were placed in Category-I and 216 in Category-II, requiring urgent or prompt remedial measures respectively.

Government Initiatives and Technology-Based Dam Safety:

DHARMA and Digital Monitoring:

• The Dam Health and Rehabilitation Monitoring Application (DHARMA) functions as a digital repository for dam inventories, inspection records, health assessments and rehabilitation monitoring.
• Digital recording of inspections strengthens data-based surveillance, transparency, institutional coordination and evidence-based maintenance planning.

Dam Rehabilitation and Improvement Project:

• DRIP Phase II and III focuses on improving dam safety and operational performance while strengthening institutional capacity; the programme has a ₹10,211 crore outlay, covers 736 dams, and is designed for a 10-year period from 2021 to 2031.
• DRIP combines physical rehabilitation, instrumentation, emergency action planning, operation and maintenance improvements, capacity building and technical standardisation.
• International Centres of Excellence for Dams at IIT Roorkee and IISc Bengaluru are supporting research and capacity building in areas including seismic analysis, sediment management, rehabilitation materials and risk assessment.

Key Challenges in India’s Dam-Safety Governance:

Technical and Institutional Gaps:

• States and dam-owning agencies vary considerably in their technical expertise, financial resources, instrumentation capacity and maintenance practices, creating uneven safety standards.
• The growing complexity of climate and seismic risks requires continuous updating of hydrological models, earthquake catalogues, geological mapping and design parameters.
• The National Committee on Seismic Design Parameters continues to develop site-specific seismic design parameters, while revised guidelines for site-specific seismic studies were issued in 2025.

Climate Change and Compound Hazards:

• Increasing variability in extreme rainfall, floods, landslides and other hazards can alter the risk profile of existing dams.
• Dam safety planning should therefore move towards multi-hazard risk assessment, integrating seismic, hydrological, geological and climate-related hazards rather than evaluating them in isolation.

Way Ahead:

• Adopt site-specific seismic assessment: Integrate PSHA and updated seismo-tectonic information into the design, rehabilitation and safety evaluation of dams in high-risk regions.
• Institutionalise periodic reassessment: Combine structural evaluation with updated hydrological and seismic data, particularly for ageing and high-consequence dams.
• Strengthen instrumentation: Expand seismic instruments, piezometers, deformation monitoring, automated weather stations and other real-time systems at vulnerable dams.
• Improve downstream preparedness: Regularly update Emergency Action Plans, dam-break analyses, flood-inundation maps and early-warning systems, followed by mock drills involving district authorities and downstream communities.
• Ensure dedicated financing: Enforce the statutory requirement for dam owners to earmark adequate funds for maintenance and repairs, preventing deferred maintenance from becoming a systemic safety risk.
• Promote risk-informed governance: Integrate consequence classification with seismic hazard, structural condition, exposure and vulnerability to prioritise rehabilitation and inspection resources.

UPSC Relevance:

GS-I — Geography:

• Seismic zones, earthquakes, Himalayan tectonics, geological hazards, river-valley projects and reservoir sedimentation.

GS-II — Governance and Federalism:

• Dam Safety Act, 2021, Centre-State coordination, regulatory institutions, statutory responsibilities and institutional capacity.

GS-III — Disaster Management and Infrastructure:

• Dam failures, disaster-risk reduction, critical infrastructure resilience, early-warning systems, climate risks and rehabilitation of ageing infrastructure.

Essay and Ethics:

• Development versus safety, intergenerational infrastructure responsibility, precautionary principle, public accountability and technology-enabled governance.

Value Addition for UPSC:

• Core Concept: Dam safety is a life-cycle risk-management issue, not merely a structural-engineering concern.
• Current Data: India has 6,628 specified dams, of which 6,545 are operational and 83 are under construction.
• Key Law: Dam Safety Act, 2021 provides the statutory architecture for surveillance, inspection, operation, maintenance and institutional coordination.
• Technology: PSHA + DHARMA + instrumentation + early-warning systems represents a transition towards risk-informed and data-driven dam safety.
• Analytical Link: The IIT Madras study demonstrates why national-scale seismic zonation should be supplemented by site-specific hazard assessment for high-consequence infrastructure.
• Mains Framework: In an answer, connect ageing dams → multi-hazard exposure → institutional capacity → technological monitoring → statutory regulation → downstream disaster preparedness.