TL;DR India has 6,628 dams holding 330 BCM of water, but the pace of new construction has slowed dramatically, from a peak of over 1,200 dams a decade in the 1970s and 80s to just 115 since 2020. Storage is unevenly spread: Maharashtra and Madhya Pradesh together hold nearly a third of the country’s capacity, while sedimentation has already eaten into roughly 20% of gross storage nationwide. Adding to the concern, 291 dams are now a century or older, together holding barely 2% of total storage, raising real questions about ageing infrastructure and safety oversight.

Context

The arrival of the southwest monsoon in India set in motion a familiar national ritual: reservoir levels watched daily, dam gates opened and closed in response to inflows, water managers across a dozen states making decisions that will shape food and power supply for the year ahead. Yet for all the attention paid to the monsoon itself, the infrastructure built to capture it receives remarkably little scrutiny. India operates more than 6,600 specified dams, ranging from decade-old ones to the Himalayan hydropower reservoirs completed within the past decade. This system surfaces in public discourse almost exclusively at moments of failure or near-failure, while the underlying data on how much water the country actually stores, where that capacity is concentrated, and how it is regulated remains largely unexamined.

Today’s article tries to step back from the usual headlines and ask a simpler question: how much water does India actually store, where is it kept, and what do the numbers tell us about a system we depend on every day without really thinking about it?

Who Compiles This Data?

The data on specified dams in India is compiled by the National Dam Safety Authority (NDSA) of India, in accordance with The Dam Safety Act, 2021. It is published in the form of the “National Register of Specified Dams”, which is a comprehensive repository of information on dams, prepared on the basis of information received from State Dam Safety Organisations/Project Authorities.

The Act defines a “Dam” broadly as any artificial barrier built to hold back or divert river water, excluding canals, flood embankments, and similar conveyance structures. A “Specified Dam” is a narrower, regulated category: any dam over fifteen metres tall qualifies automatically, while dams between ten and fifteen metres count only if they also meet specific risk thresholds, such as reservoir capacity, crest length, flood-discharge capacity, foundation difficulty, or unusual design. Height and risk together decide which dams face closer regulatory scrutiny.

Where can I download Clean & Structured Data on Dams & Dam Safety in India?

Clean, standardised, structured, and ready-to-use datasets on Dams in India, their storage, and their state-wise presence are available on Dataful.

Key Insights

Storage Capacity of Specified Dams Reveals Sharp Regional Disparities

Maharashtra leads the country with 2,696 specified dams, of which 2,691 are completed, yet its gross storage capacity of 46.789 billion cubic metres (BCM) is barely ahead of Madhya Pradesh’s 46.255 BCM, a figure achieved with fewer than half as many structures (1,370). The contrast underscores that the sheer number of dams does not translate proportionally into storage capacity, a consideration with direct bearing on the cost-effectiveness of future investment decisions.

Maharashtra, Madhya Pradesh, Gujarat (525) and Chhattisgarh (322) together account for a substantial share of India’s 6,628 dams, pointing to heavy regional concentration of water-storage infrastructure, even as several states, particularly across the Northeast, hold only single-digit counts.

Nationally, live storage capacity stands at 265.544 BCM against a gross capacity of 330.022 BCM, a gap of roughly 20% attributable largely to sediment accumulation over time, a long-flagged concern for dam safety authorities. Under-construction activity is most pronounced in Telangana (16 dams), Andhra Pradesh (13) and Jharkhand (5). Notably, Andhra Pradesh’s under-construction dams alone account for 10.826 BCM of gross capacity, more than half its completed total, signalling significant pending construction of dams.

Six Decades of Dam-Building: A Slowing Momentum

India’s dam-building history reflects distinct phases of state-led infrastructure expansion. Construction before 1900 added just 125 structures, a figure that rose modestly through the first half of the twentieth century, with 277 dams built between 1901 and 1950. The pace accelerated after independence, with the 1961-70 decade recording 488 new dams, more than double the figure for the preceding decade.

The most intensive period of construction occurred between 1971 and 1990, when 1,224 and 1,231 dams were added in successive decades, respectively, reflecting the era’s emphasis on irrigation expansion and hydropower development under successive five-year plans. Activity moderated through the 1990s, falling to 857 dams, before recovering to 1,049 between 2001 and 2010.

Since then, the trend has reversed sharply. Additions fell to 946 dams in 2011-2020, and only 115 have been recorded beyond 2020. With only 83 dams currently under construction nationwide, against a base of 6,545 completed structures, the data point to a marked slowdown in new dam construction even as water demand continues to climb amid population growth and climate variability, raising policy questions about how future storage and irrigation needs will be met as the era of large dam-building winds down.

Almost 300 Dams in India that are over 100 years old

When a dam crosses the hundred-year mark, the question is no longer just how much water it holds, but whether it can still be trusted to hold it. There are 291 dams aged a century or more, spread unevenly across the country. Maharashtra alone accounts for 61 of them, followed by Madhya Pradesh with 44, Rajasthan with 39, Andhra Pradesh with 32, and Karnataka with 29.

What stands out is how little water these old structures actually hold. Together, they store roughly 7.9 billion cubic metres, just over 2% of the country’s total specified dam gross storage, even though they make up close to 4.5% of all dams.

That mismatch between age and scale is exactly why dam safety is crucial. A century-old earthen embankment may be small, but it still sits above villages and farmland, often with patchy maintenance records and reduced storage from decades of silt. The Dam Safety Act of 2021 was meant to bring these ageing structures under closer watch.

Why Does It Matter?

Dams underpin much of India’s irrigation, drinking water, and electricity supply, yet new construction has slowed sharply just as climate change makes rainfall less predictable. At the same time, hundreds of structures built over a century ago continue to operate above farmland and villages, often holding little water relative to their age and carrying patchy maintenance records. Tracking how many dams exist, how much water they hold, and how old they are is essential for planning water security and for spotting where safety risks are concentrated.

Key Numbers

• Total Specified Dams and their Gross Storage Capacity, as of 2025

  • Maharashtra: 2,696 dams, 46.789 BCM gross storage

  • Madhya Pradesh: 1,370 dams, 46.255 BCM gross storage

  • Gujarat: 525 dams, 26.948 BCM gross storage

  • Chhattisgarh: 322 dams, 7.878 BCM gross storage

  • All India: 6,628 dams, 330.022 BCM gross storage, 265.544 BCM live storage

• Dams that are over 100 years of age

  • Dams aged 100+ years: 291, about 4.4% of all dams in India

  • Maharashtra: 61; Madhya Pradesh: 44; Rajasthan: 39; Andhra Pradesh: 32; Karnataka: 29

  • Combined gross storage of these old dams: about 7.9 BCM, just over 2% of national storage

• Decade-wise construction of specified dams

  • Up to 1900: 125 dams built

  • 1971–1990: peak building years, 1,224 and 1,231 dams added in successive decades

  • 2011–2020: fell to 946 dams

  • Beyond 2020: just 115 dams added