Dam Rehabilitation in India

India today manages one of the world’s largest dam portfolios and ranks third globally in terms of the number of dams. According to official data, India has 6,628 specified dams, of which 6,545 are operational and 83 are under construction.  The total gross water storage capacity of these dams is about 330 billion cubic metres.

These dams play a crucial role in ensuring food security, energy security and water security. 

Ageing Dam Infrastructure: A significant proportion of India’s dams are ageing infrastructure. 

• About 26% (1,681 dams) are more than 50 years old
• 291 dams are more than 100 years old
• Around 42% fall within the 25–50 years age bracket

India’s oldest functioning dam, the Kallanai (Grand Anicut) in Tamil Nadu, has remained operational for nearly 2,000 years and is considered a remarkable example of ancient engineering excellence.

Ownership Pattern of Dams: The majority of dams in India are owned by State Governments. Ownership Distribution:

• State Governments: 6,448 dams (98.5%)
• Central Public Sector Undertakings: 49 dams (0.7%)
• Private entities: 36 dams (0.6%)
• Central Government: 12 dams (0.2%)

States with Highest Number of Dams: Maharashtra has the highest number of specified dams in India, followed by Madhya Pradesh and Gujarat. 

Loss of Reservoir Storage Capacity: Analysis conducted on 439 reservoirs using Central Water Commission (CWC) data revealed:

• Average loss of gross storage capacity: 19%
• Average reservoir age: 42 years
• Average annual storage loss: 0.74%

This translates to approximately 1.81 million cubic metres (MCM) of storage loss per reservoir annually. 

Dam Rehabilitation and Improvement Project (DRIP): The Dam Rehabilitation and Improvement Project (DRIP) is being implemented in three phases to enhance:

• Structural safety
• Operational efficiency
• Monitoring systems of existing dams.

DRIP is regarded as one of the world’s largest dam rehabilitation programmes and reflects India’s transition toward a systematic and risk-based dam safety management framework.

Dam Safety Act, 2021

The Dam Safety Act, 2021 came into force on 30 December 2021. The Act provides a comprehensive legal framework for surveillance, inspection, operation and maintenance of specified dams.  A specified dam refers to a dam more than 15 metres in height, or a dam between 10 and 15 metres in height fulfilling prescribed technical criteria. Compliance with the provisions of the Act has become a statutory obligation for dam owners with fixed timelines.

Four-Tier Institutional Mechanism: The Act establishes a four-tier institutional structure:

1. National Committee on Dam Safety (NCDS): The apex policy body responsible for:

• Framing dam safety policies
• Recommending regulations
• Ensuring uniform safety standards nationwide

2. National Dam Safety Authority (NDSA): Functions as:

• Regulatory authority
• Implementing agency

3. State Committees on Dam Safety (SCDS): 

4. State Dam Safety Organisations (SDSO).  

Inspection and Classification of Dams: Under regulations notified on 24 April 2024, dam owners are mandated to conduct Pre-monsoon inspections and Post-monsoon inspections.

Source: PIB