SCARY! Weak Monsoon Threatens Water Security

'Monsoon is the pran (life) of our water system.'
'A weak monsoon will have a very negative impact on crops and people's lives.'

As El Niño conditions strengthen over the Pacific this year, concerns are mounting over India's monsoon outlook.

According to the India Meteorological Department (IMD), the country could see a 'below normal' monsoon in 2026 for the first time in three years if its April forecast turns out to be accurate.

It estimates that the southwest monsoon will likely be at 92 per cent of the long period average (LPA), marking the first below-normal season since 2023.

(LPA, according to the IMD, is the average rainfall recorded over a particular region for a given interval, like a month or a season, over a long period, such as 30 or 50 years.)

El Nino Monsoon Impact India

The Met department has also indicated that most parts of the country, barring some areas in the Northeast, Northwest and the southern peninsula, are likely to receive below-normal rainfall this year.

Noida-headquartered private weather agency Skymet has echoed this outlook.

In its 2026 forecast, it pegged rainfall at 94 per cent (plus/minus 5 per cent) of the long-period average of 868.6 mm for the June-September monsoon season.

While these figures may not appear drastically low on paper, experts caution that even a marginal shortfall -- particularly when coupled with uneven spatial and temporal distribution -- can have disproportionate consequences for India's already stressed water systems.

India is among the most water-stressed countries in the world.

If the forecast holds, it could trigger cascading effects on agriculture and drinking water supply, further straining an already fragile water security framework.

The Lifeline Called Monsoon

Nearly 45 per cent of India's rain-fed agriculture depends on the monsoon, with the timing and adequacy of rainfall playing a critical role in crop outcomes.

According to NITI Aayog's Composite Water Management Index (CWMI) as in 2019, about 74 per cent of wheat-growing areas and 65 per cent of rice cultivation zones already face significant water stress.

CWMI estimates suggest that the demand-supply gap in agricultural water could reach 570 billion cubic metres (BCM) by 2030.

Groundwater, which accounts for 62 per cent of irrigation, has been declining in over half of the monitored regions, pointing to a deep and persistent imbalance.

"Monsoon is the pran (life) of our water system," said water conservationist Rajendra Singh, a Ramon Magsaysay Awardee and Stockholm Water Prize winner.

"A weak monsoon will have a very negative impact on crops and people's lives."

Singh argues that India's increasing shift towards commercial crops and industrial expansion has deepened its dependence on monsoon rainfall.

"Our economic model has made us more vulnerable," he said.

Himanshu Thakkar, coordinator of the South Asia Network on Dams, Rivers and People, echoed similar concerns: "It is worrying that rainfall may be deficient while temperatures are expected to be high.

Higher temperatures will increase evaporation losses, and if rainfall is also deficient, that will create additional stress."

Rainfall Distribution Risk

Experts stress that beyond the overall deficit, rainfall distribution will be critical, particularly for agriculture.

Thakkar emphasised the importance of timing.

"What matters more is the distribution of rainfall. If rainfall is near normal during key crop stages, the situation may still be manageable," he said.

However, if deficits occur during critical phases such as early growth or flowering, the impact on rain-fed agriculture can be severe, he added.

Reservoir Levels Monsoon Buffer

Reservoir levels currently offer a temporary cushion, though one that is already shrinking.

The Central Water Commission (CWC) tracks the live storage of 166 major reservoirs, which together have a capacity of 183.565 BCM, about 71.20 per cent of India's estimated total reservoir capacity of 257.812 BCM.

According to a bulletin dated April 9, 2026, storage stood at 82.070 BCM, or 44.71 per cent of total capacity, at these reservoirs.

This is higher than last year's level of 69.752 BCM and above the 10-year average of 64.618 BCM.

This indicates that current reservoir storage is about 117.66 per cent of last year's level and 127.01 per cent of the decadal average.

However, reserves have been declining sharply in recent months.

Storage dropped from 126.354 BCM (68.83 per cent) of total capacity on January 29 to 85.698 BCM (46.69 per cent) on April 2, and further to 82.070 BCM by April 9.

Experts attribute the relatively comfortable levels to a strong monsoon in 2025 and subsequent rainfall.

But weak pre-monsoon showers and a subdued monsoon outlook could quickly erode this buffer.

Tap Into The Ground, Too

What makes the situation more precarious is not just the prospect of lower rainfall, but the declining effectiveness of natural recharge systems.

Groundwater aquifers, which serve as India's largest freshwater reserves, depend on steady, well-distributed rainfall for replenishment.

However, shifting rainfall patterns, marked by short, intense bursts rather than sustained moderate showers, are reducing the amount of water that seeps into the ground.

"There used to be water bodies such as lakes in every village that acted as water banks, but we have failed to build storage infrastructure in line with rising demand, leading to both drought and floods," Singh said.

"Water banks help recharge aquifers and reduce the loss of water through evaporation."

Lower rainfall is likely to intensify pressure on groundwater, as extraction rises to meet agricultural and domestic demand even as replenishment slows.

"Most of the water we use is groundwater, but levels are falling. That is our lifeline," Thakkar said.

Data from the Central Ground Water Board (CGWB) shows that 87 per cent of groundwater extracted in India is used for agriculture, while about 11 per cent is for domestic consumption.

According to the Groundwater Resource Assessment of India 2025, total annual recharge stands at 448.52 BCM, with extractable resources at 407.75 BCM.

Total extraction in 2025 was 247.22 BCM, placing the overall stage of groundwater extraction at 60.63 per cent.

Of 6,762 assessment units, 730 (10.80 per cent) are classified as 'overexploited', where groundwater extraction exceeds recharge; 201 (2.97 per cent) are 'critical'; 758 (11.21 per cent) are 'semicritical'; and 4,946 (73.14 per cent) are 'safe'.

Besides these, 127 (1.88 per cent) units have saline groundwater.

However, national averages mask sharp regional stress.

States such as Delhi, Haryana, Punjab, Rajasthan and Tamil Nadu have more than a quarter of their units in overexploited or critical categories.

Experts emphasise that rainfall alone is not enough.

How effectively it translates into groundwater recharge is equally crucial.

More than 75 per cent of India's annual rainfall occurs during the four monsoon months, (June to September) leading to sharp seasonal imbalances.

Rainfall remains the primary source of groundwater recharge.

"Much of the rainwater that could be stored for later use simply flows away. This is one of the country's biggest losses," Singh said.

CGWB data shows that rainfall contributes 269.17 BCM (about 60 per cent) to total groundwater recharge: 54.7 per cent during the monsoon and 5.3 per cent in the non-monsoon period.

The remaining 40 per cent comes from sources such as canal seepage, irrigation return flows, and recharge through tanks, ponds and water conservation structures.

"Rainfall is the most important source of recharge, but how it translates into groundwater depends on the systems we maintain," Thakkar said, pointing to ponds, tanks, lakes, wetlands, forests, rivers and streams as critical recharge structures.

"All of these systems need to be protected and strengthened. Desilting local water bodies, for instance, improves both storage capacity and recharge," he said, adding, "The problem is we are not doing enough. If groundwater is our primary source, we need far greater efforts to ensure its sustainability."

He outlined two key solutions: Reducing groundwater use through better governance, and significantly enhancing recharge.

Singh offered a stark warning: "If we do not recharge our aquifers, how will we meet future needs? If India is to become drought- and flood-resilient, we must learn to capture and store rainwater."

Even as reservoir levels offer a temporary buffer, the outlook makes a case for more resilient water management as India heads into an uncertain monsoon season.

Feature Presentation: Ashish Narsale/Rediff