India scales up dam-safety rehabilitation under DRIP and the Dam Safety Act 2021 with a four-tier NCDS–NDSA–SCDS–SDSO architecture.
Why in News
India is undertaking one of the world's largest dam rehabilitation and safety modernisation programmes to strengthen ageing water infrastructure. The push combines the Dam Rehabilitation and Improvement Programme (DRIP) — a World Bank-aided multi-phase scheme begun in 2012 — with the statutory framework of the Dam Safety Act, 2021, mandatory pre-monsoon and post-monsoon inspections, and the digital DHARMA platform. The Supreme Court has flagged uneven implementation across States. India hosts 6,628 specified dams, the third-largest dam network globally after the US and China. Around 26% (1,681) are over 50 years old, reservoirs have lost about 19% of gross storage to sedimentation, and incidents like the 2001 Bhuj earthquake (Chang Dam) and the 2023 Chungthang Dam glacial-lake-outburst breach in Sikkim underline structural vulnerability.
At a Glance
- India's specified-dam count
- 6,628, third globally after the US and China.
- 98.5% of specified dams are owned by State Governments; Centre owns a tiny share.
- Top States by dam count
- Maharashtra > Madhya Pradesh > Gujarat.
- 26% (1,681 dams) are over 50 years old — ageing infrastructure risk.
- Sedimentation has cut average reservoir storage by about 19%.
- DRIP (2012)
- World Bank-aided, multi-phase rehabilitation of selected dams.
- Dam Safety Act, 2021
- governs surveillance, inspection, O&M of specified dams.
- 4-tier structure
- NCDS (policy) → NDSA (national regulator) → SCDS → SDSO.
- DHARMA
- digital asset-management platform for dam data and inspections.
- Mandatory pre-monsoon and post-monsoon inspections of all specified dams.
- Seismic risk
- 2001 Bhuj quake caused liquefaction in Chang Dam foundation.
- GLOF risk
- 2023 South Lhonak Lake outburst breached Chungthang Dam, Sikkim.
- Specified dam = >15 m height OR 10–15 m with defined storage/spillway criteria.
- Climate variability — erratic monsoons and extreme rainfall — is a rising stressor.
India's dam network at a glance
India operates 6,628 specified large dams, making it the third-largest dam-owning nation after the United States and China. About 98.5% are owned by State Governments, with Central PSUs and private owners holding the rest. Maharashtra leads in numbers, followed by Madhya Pradesh and Gujarat. Most major dams are multipurpose — supporting irrigation, hydropower, drinking water, flood moderation and industrial supply — making safety failures simultaneously a livelihood, economic and disaster-risk concern. A 'specified dam' under the Dam Safety Act, 2021 generally means a dam above 15 metres in height, or between 10–15 m with specific design or reservoir characteristics; these are the dams brought under the central regulatory net.
Key safety challenges
Ageing infrastructure is the foremost risk: 26% (1,681) of specified dams are over 50 years old, with several over a century old. Sedimentation has reduced average reservoir storage by ~19%, eroding flood-cushion and live-storage capacity. Seismic vulnerability was exposed by the 2001 Bhuj earthquake, which triggered liquefaction in the foundation of Chang Dam (Gujarat). Glacial Lake Outburst Floods (GLOFs) are a growing Himalayan threat — in October 2023, the South Lhonak Lake outburst flash-flood washed away the Chungthang Dam of the Teesta-III hydro project in Sikkim. Other stressors include shifting hydrological patterns under climate change, encroachment in spillway zones and weak emergency-action planning.
DRIP — Dam Rehabilitation and Improvement Programme
DRIP is a multi-phase programme launched in 2012 with World Bank assistance to rehabilitate selected dams across India. Phase-I (2012–2020) covered around 223 dams in seven States. Phase-II and Phase-III (approved 2020–21) extend the scope to roughly 736 dams across 19 States and three Central agencies, with an outlay of about ₹10,211 crore over ten years, co-financed by the World Bank and Asian Infrastructure Investment Bank (AIIB). DRIP funds structural rehabilitation, dam-safety inspections, emergency action plans (EAPs), instrumentation, training and the development of the DHARMA digital platform. It also supports research, dam-break analyses and capacity-building of dam owners.
Dam Safety Act, 2021 — 4-tier structure
The Dam Safety Act, 2021 provides for surveillance, inspection, operation and maintenance of specified dams across India and creates a uniform regulatory architecture. Its four-tier institutional structure comprises: (i) National Committee on Dam Safety (NCDS) — evolves policy and recommends regulations; (ii) National Dam Safety Authority (NDSA) — implements policy, resolves inter-State disputes, regulates State agencies; (iii) State Committee on Dam Safety (SCDS) in each State; and (iv) State Dam Safety Organisations (SDSOs) for day-to-day surveillance. The Act mandates periodic and post-event inspections, comprehensive dam-safety reviews, emergency action plans, and penalties — including imprisonment — for obstruction or non-compliance.
Digital and inspection initiatives
The Dam Health and Rehabilitation Monitoring Application (DHARMA) is the NDSA's web-based asset-management tool that digitises dam-safety data — design, instrumentation, inspections, incidents, repairs — for every specified dam. Mandatory pre-monsoon and post-monsoon inspections are required for all specified dams, with reports uploaded to DHARMA. The NDSA also publishes the National Dam Safety Policy, model emergency action plans, and Guidelines for Safety Inspection. Complementary initiatives include the Seismic Hazard Atlas for dams, GLOF early-warning systems for Himalayan reservoirs, and capacity-building under the National Water Academy (NWA), Pune. The Supreme Court has, in recent hearings, flagged uneven State-level implementation, especially delays in constituting SCDS/SDSOs and finalising EAPs.
Way forward
Experts urge risk-based prioritisation — focusing rehabilitation funds on the highest-hazard, highest-consequence dams rather than uniform State-wise allocation. Decommissioning of obsolete or unsafe dams must become a legitimate policy option, as in the United States. Sediment management through flushing, sluicing and watershed treatment can recover storage. GLOF risk demands dynamic operating rules and downstream early-warning. Finally, independent dam-safety audits, public disclosure of inspection reports through DHARMA, and stronger penalties under the 2021 Act are needed for genuine accountability. The Dam Safety Act 2021's central-State balance — challenged by some States as encroaching on water, a State subject — remains under judicial scrutiny.
Must Remember
- •India has the world's third-largest dam network with 6,628 specified dams after the United States and China.
- •About 98.5% of India's specified dams are owned by State Governments, with Maharashtra topping the list.
- •About 26% (1,681) of India's specified dams are more than 50 years old, raising ageing-infrastructure risks.
- •Indian reservoirs have lost on average about 19% of gross storage capacity due to sedimentation.
- •The Dam Safety Act, 2021 created a 4-tier structure: NCDS, NDSA, SCDS and SDSOs.
- •DRIP is a World Bank-aided dam rehabilitation programme launched in 2012, now in Phase-II and Phase-III.
- •DHARMA is the digital platform for dam health and rehabilitation monitoring under the NDSA.
- •Maharashtra has the highest number of specified dams, followed by Madhya Pradesh and Gujarat.
| Rank | State | Status |
|---|---|---|
| 1 | Maharashtra | Highest number of specified dams |
| 2 | Madhya Pradesh | Second-highest |
| 3 | Gujarat | Third-highest |
Static GK
- •: India is the third-largest dam-owning country in the world after the United States and China.
- •: Bhakra Dam on the Sutlej is one of India's tallest gravity dams, in Himachal Pradesh.
- •: Tehri Dam, in Uttarakhand on the Bhagirathi, is the tallest dam in India at about 260.5 m.
- •: Idukki Dam in Kerala on the Periyar is one of Asia's largest arch dams.
- •: Hirakud Dam on the Mahanadi in Odisha is one of the longest earthen dams in the world.
- •: Sardar Sarovar Dam on the Narmada is the second-largest concrete gravity dam in the world by volume.
- •: Nagarjuna Sagar Dam is a masonry dam across the Krishna river in Telangana–Andhra Pradesh.
- •: Mettur Dam is across the Cauvery river in Tamil Nadu and supports the Stanley Reservoir.
- •: The Dam Safety Act, 2021 came into force from 30 December 2021.
- •: The Central Water Commission (CWC) advises the Government of India on water-resource development and dam safety.
- •: ICOLD — International Commission on Large Dams — sets global technical standards for large dams.
- •: Three Gorges Dam on the Yangtze in China is the world's largest hydropower dam by installed capacity.
- •: Hoover Dam is on the Colorado river between Nevada and Arizona in the United States.
- •: The 1979 Machchhu-II dam failure in Morbi, Gujarat is one of India's worst dam disasters.
- •: India's National Register of Large Dams (NRLD) is maintained by the Central Water Commission.
- •: Glacial Lake Outburst Flood risk is concentrated in the Himalayan States — Sikkim, Uttarakhand, Himachal Pradesh, Arunachal Pradesh.
Glossary
- Specified dam
- A dam above 15 m height, or between 10–15 m with defined storage/spillway criteria, brought under the Dam Safety Act, 2021.
- DRIP
- Dam Rehabilitation and Improvement Programme, a multi-phase World Bank-aided scheme launched in 2012 to rehabilitate large dams.
- NCDS
- National Committee on Dam Safety — apex policy body under the Dam Safety Act, 2021, evolving national dam-safety norms.
- NDSA
- National Dam Safety Authority — central regulator implementing policy, regulating SDSOs and resolving inter-State dam disputes.
- SCDS
- State Committee on Dam Safety — State-level body that reviews dam-safety performance and approves rehabilitation plans.
- SDSO
- State Dam Safety Organisation — implementing agency for inspection, surveillance and O&M of dams within a State.
- DHARMA
- Dam Health and Rehabilitation Monitoring Application — NDSA's digital platform for dam data, inspections and incidents.
- Emergency Action Plan (EAP)
- Pre-prepared plan for actions, evacuations and downstream communication in case of imminent dam failure or extreme flood.
- GLOF
- Glacial Lake Outburst Flood — sudden release of water from a moraine-dammed glacial lake, causing catastrophic downstream flooding.
- Sedimentation
- Accumulation of silt and sediment in a reservoir over time, reducing live and dead storage capacity of the dam.
- Liquefaction
- Process by which saturated soil temporarily loses strength during an earthquake, behaving like a liquid and threatening foundations.
- Spillway
- Structure that safely passes excess flood water over or around a dam to prevent overtopping and structural failure.
- Pre/post-monsoon inspection
- Mandatory inspection of specified dams before and after the monsoon to assess structural integrity and operational readiness.
- Risk-based prioritisation
- Approach that ranks dams by hazard class and consequence of failure to allocate scarce rehabilitation resources efficiently.
Timeline
- 1900Many of India's currently functioning dams begin their service life — large pre-Independence dam construction era.
- 1979Machchhu-II Dam (Morbi, Gujarat) failure becomes one of India's worst dam disasters.
- 1987Government of India sets up the Dam Safety Organisation under the Central Water Commission (CWC).
- 2001Bhuj earthquake (Gujarat) causes liquefaction in the foundation of Chang Dam, exposing seismic risks.
- 2012Dam Rehabilitation and Improvement Programme (DRIP) Phase-I launched with World Bank assistance.
- 2020DRIP Phase-II and Phase-III approved by the Government with World Bank and AIIB co-financing.
- December 2021Dam Safety Act, 2021 enacted by Parliament and notified into force on 30 December 2021.
- 2022National Dam Safety Authority (NDSA) operationalised under the Act.
- October 2023South Lhonak GLOF in Sikkim washes away the Chungthang Dam of Teesta-III hydro project.
- 2024Supreme Court takes cognisance of implementation gaps under the Dam Safety Act.
- 2025DHARMA platform expanded to cover most specified dams across States.
- May 2026Renewed policy focus on DRIP Phase-II/III delivery and Dam Safety Act compliance.
- →India has 6,628 specified dams — third globally after the US and China.
- →98.5% of specified dams are owned by State Governments.
- →26% (1,681) of specified dams are more than 50 years old.
- →Sedimentation has cut reservoir storage by an average of 19%.
- →DRIP started in 2012 with World Bank funding — multi-phase, multi-State.
- →Dam Safety Act, 2021 — notified 30 December 2021.
- →4-tier structure: NCDS → NDSA → SCDS → SDSO.
- →DHARMA = Dam Health and Rehabilitation Monitoring Application.
- →Pre-monsoon and post-monsoon inspections are mandatory for specified dams.
- →2001 Bhuj earthquake — Chang Dam (Gujarat) foundation liquefaction.
- →2023 Chungthang Dam (Sikkim) washed away by South Lhonak GLOF.
- →Maharashtra has the most specified dams in India.
- →Tehri Dam (Uttarakhand) is India's tallest dam at ~260.5 m.
- →Sardar Sarovar Dam is across the Narmada river.
- →ICOLD sets international standards for large dams.
- →NDSA — central regulator created by the Dam Safety Act, 2021.
- →Specified dam: >15 m height, or 10–15 m with defined criteria.
- →DRIP also co-financed by Asian Infrastructure Investment Bank (AIIB).
Exam Angles
India advances its world-class dam-safety push — 6,628 dams, DRIP Phase-III rehabilitation, the Dam Safety Act 2021 institutional structure and DHARMA digital monitoring.
Q1. India is currently the third-largest dam-owning country in the world, with how many specified large dams as per the National Register of Large Dams?
- A.About 6,628 specified dams
- B.About 4,500 specified dams
- C.About 9,200 specified dams
- D.About 3,300 specified dams
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Answer: A. About 6,628 specified dams
India has about 6,628 specified large dams, ranking third globally after the United States and China. Around 98.5% are State-owned, with Maharashtra holding the largest number. The other options misstate India's dam count.
Q2. Under the Dam Safety Act, 2021, which body is the central regulator for implementation of dam-safety policy across India?
- A.National Dam Safety Authority (NDSA)
- B.Central Water Commission (CWC)
- C.National Committee on Dam Safety (NCDS)
- D.National Disaster Management Authority (NDMA)
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Answer: A. National Dam Safety Authority (NDSA)
The National Dam Safety Authority (NDSA) is the central regulator under the Act, while NCDS evolves policy. The CWC advises Government on water resources but is not the statutory regulator. NDMA handles disasters in general, not dam-safety regulation.
Q3. The term 'Glacial Lake Outburst Flood (GLOF)' is best described as:
- A.The sudden release of water from a glacial lake, often after moraine or ice-dam failure, causing catastrophic downstream flooding
- B.An extreme flood event caused by very high monsoon rainfall in semi-arid catchments where soils fail to absorb water in time
- C.An incident of liquefaction in dam foundations during a major seismic event, threatening the structural stability of the dam
- D.An overflow of reservoirs caused by gradual sedimentation over decades that reduces the live storage of the reservoir
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Answer: A. The sudden release of water from a glacial lake, often after moraine or ice-dam failure, causing catastrophic downstream flooding
A GLOF is the sudden release of water from a glacier-fed lake when its natural dam fails, e.g., the 2023 South Lhonak event that breached the Chungthang Dam in Sikkim. The other options describe distinct hazards — pluvial flood, liquefaction and sediment loss.
Q4. Consider the following pairs about the four-tier dam-safety structure under the Dam Safety Act, 2021:
1. NCDS — National-level policy body
2. NDSA — Central implementing/regulatory authority
3. SCDS — State-level committee for dam safety
4. SDSO — State-level surveillance and inspection agency
Which of the above pairs is/are correctly matched?
- A.1, 2, 3 and 4
- B.1 and 2 only
- C.2 and 3 only
- D.1, 3 and 4 only
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Answer: A. 1, 2, 3 and 4
All four pairs are correct. NCDS evolves policy, NDSA is the national regulator, SCDS is the State committee, and SDSO is the field-level surveillance and inspection agency. Hence all four pairs are correctly matched.
Q5. Consider the following statements:
1. India has the second-largest dam network in the world after China.
2. About 26% of India's specified dams are more than 50 years old.
3. The Dam Rehabilitation and Improvement Programme (DRIP) is supported by the World Bank.
4. DHARMA is a Central law replacing the Dam Safety Act, 2021.
Which of the above statements is/are correct?
- A.2 and 3 only
- B.1, 2 and 3 only
- C.1 and 4 only
- D.1, 2, 3 and 4
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Answer: A. 2 and 3 only
Statement 1 is incorrect — India ranks third, after the US and China. Statement 2 is correct — ~26% of dams are over 50 years old. Statement 3 is correct — DRIP is World Bank-aided (and now AIIB-co-financed). Statement 4 is incorrect — DHARMA is a digital monitoring platform, not a statute.
Q6. Consider the following statements:
1. It provides for surveillance, inspection, operation and maintenance of specified dams in India.
2. It creates a four-tier institutional structure for dam safety.
3. It mandates pre-monsoon and post-monsoon inspections of specified dams.
4. It exempts State-owned dams from any central regulatory oversight.
How many of the above statements are correct?
- A.Only three
- B.All four
- C.Only two
- D.Only one
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Answer: A. Only three
Statements 1, 2 and 3 are correct — the Act covers O&M, sets up the NCDS–NDSA–SCDS–SDSO structure, and requires pre/post-monsoon inspections. Statement 4 is incorrect — even State-owned specified dams come under central oversight via NDSA, which is one reason some States have challenged the Act. Hence three statements are correct.
Q7. In October 2023, which dam in Sikkim was washed away by a glacial-lake outburst flood originating from the South Lhonak Lake?
- A.Chungthang Dam, Teesta-III project
- B.Rangit Dam, on the Rangit river
- C.Teesta-V Dam, on the Teesta river
- D.Dikchu Dam, on the Dikchu river
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Answer: A. Chungthang Dam, Teesta-III project
The Chungthang Dam of the Teesta-III hydroelectric project was washed away in October 2023 when the South Lhonak Lake burst, sending a flash flood down the Teesta valley. Rangit, Teesta-V and Dikchu dams suffered damage but were not destroyed.
India's dam stock — the third-largest in the world — is simultaneously a developmental asset and an emerging liability. Many of the country's strategic reservoirs were built in the 1950s–70s and are now ageing, sediment-choked and exposed to seismic and climate-driven hazards such as GLOFs. The Dam Safety Act, 2021 represents the first all-India regulatory architecture, but its implementation lags, with the Supreme Court flagging gaps. Programmes like DRIP, digital platforms like DHARMA and improved emergency-action planning together define India's response, but federal frictions and weak State capacity remain.
- Federal architecture of dam safetyThe Dam Safety Act creates a **central regulator over State-owned dams**, testing the cooperative-federal balance, particularly because 'Water' is a **State subject**. Sustained Centre–State dialogue and adequate State funding are essential to avoid token compliance.
- Ageing and sediment-choked reservoirsWith **26% of dams over 50 years old** and **19% average storage loss to sedimentation**, India faces both safety and water-security risks. Without **risk-based prioritisation**, scarce funds will be spread thinly across politically symbolic projects.
- Climate-driven new risks (GLOFs)The **2023 Chungthang Dam failure** showed that Himalayan reservoirs face **non-traditional hazards** that conventional design codes underestimate. New dynamic operating rules and downstream early-warning are needed for **Sikkim, Uttarakhand and Arunachal Pradesh**.
- Risk-based, transparent regulationAdopt **hazard-classification of dams**, publish DHARMA inspection reports, mandate **independent third-party audits**, and create a fiscal window for **decommissioning** of obsolete or unsafe dams, as practised in the United States.
- Building State capacityMany SDSOs are under-resourced and dominated by reservoir-operation engineers rather than safety specialists. Investment in **training (NWA Pune)**, instrumentation and forensic dam-break analyses will determine whether the 2021 Act becomes genuinely transformative.
Mains Q · 250wIndia's dam-safety challenge is no longer purely engineering — it is governance, climate and federalism. Critically examine the institutional framework created by the Dam Safety Act, 2021 and DRIP, and suggest a way forward. (15 marks, 250 words)
Q1. Which of the following is a key constitutional concern raised by some States against the Dam Safety Act, 2021?
- A.It allegedly encroaches upon 'Water' which is a State subject under Entry 17 of the State List
- B.It violates Article 21 by criminalising negligence by dam owners
- C.It overrides Article 19(1)(g) by restricting commercial use of reservoirs
- D.It conflicts with the Inter-State River Water Disputes Act, 1956
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Answer: A. It allegedly encroaches upon 'Water' which is a State subject under Entry 17 of the State List
The Act has been challenged by some States on the ground that 'Water' falls under Entry 17 of the State List, and central regulation of State-owned dams allegedly encroaches on State legislative competence. The Centre defends the Act under entries linked to inter-State rivers and national disaster management. The other options are not the principal challenges.
Q2. Under the Dam Safety Act, 2021, willful obstruction or non-compliance with directions of dam-safety authorities can lead to:
- A.Imprisonment up to two years and/or fine, depending on the offence
- B.Only a monetary penalty with no imprisonment
- C.Only departmental action against State officials
- D.Civil compensation alone, no criminal liability
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Answer: A. Imprisonment up to two years and/or fine, depending on the offence
The Act includes penal provisions, allowing imprisonment (up to about two years) and/or fine for offences such as obstructing officials or non-compliance with safety directions, in addition to civil liability. Pure monetary or departmental remedies do not capture the Act's penal architecture.
Flashcard
Q · India advances its world-class dam-safety push — 6,628 dams, DRIP Phase-III rehabilitation, the Dam Safety Act 2021 institutional structure and DHARMA digital monitoring.tap to reveal
Connections & Comparisons
- ↔Pairs with: undersea-cables-vulnerability-2026 — both illustrate India's exposure to critical-infrastructure shocks (water vs. data).
- ↔Compare with: Three Gorges Dam (China) and Hoover Dam (USA) — global benchmarks for large-dam governance and decommissioning.
- ↔Track jointly: DRIP outlay (₹10,211 crore), share of dams >50 years old (26%) and DHARMA coverage progress.
- ↔Strategic frame: Dam Safety Act 2021 + Disaster Management Act 2005 — twin pillars of infrastructure-disaster governance.
- ↔Historical parallel: 1979 Machchhu-II failure (Morbi, Gujarat) — landmark that shaped Indian dam-safety thinking.