Why monsoon rains wreak havoc annually in India's cities

Heavy rains last month caused widespread flooding in Mumbai

"Who is responsible for this mess?"

The question recently echoed across India's financial capital Mumbai as thousands of residents once again found themselves stranded, soaked and frustrated.

Heavy rains brought the city to a standstill, and this was before the monsoon had even begun in full swing. Roads turned into rivers, vehicles broke down mid-commute and low-lying neighbourhoods were waterlogged within hours.

Even a newly-built underground metro station could not withstand the heavy downpour as photos and videos of the station flooded with muddy water went viral.

The pre-monsoon deluge once again exposed the city's fragile infrastructure and sparked widespread outrage on social media.

The Brihanmumbai Municipal Corporation (BMC), one of India's richest civic organisations responsible for maintaining Mumbai's infrastructure, initially blamed the problem on rubbish clogging the drains and debris from metro construction, The Hindustan Times newspaper reported.

Following criticism, the BMC installed de-watering pumps in flood-prone areas and began manually clearing waste from drains to prevent further waterlogging. But for many residents, the action came too late.

The crisis is neither new - nor is it unique to Mumbai.

From Delhi in the north to Bengaluru in the south, India's biggest cities flood every monsoon season. Roads collapse, drains overflow, infrastructure is overwhelmed and traffic grinds to a halt.

Experts blame rapid unplanned urbanisation, poor infrastructure and years of environmental neglect as the root causes of this problem.

Delhi's Minto bridge is flooded every year during the monsoon

"The pace of urban expansion has far exceeded the evolution of supporting infrastructure, particularly in water and drainage systems," says Dikshu Kukreja, an architect and urban planner based in Delhi.

"Many cities rely on outdated systems designed decades ago. And in the process of unchecked expansion, natural drainage channels, wetlands and water bodies that once absorbed excess rainwater have been built over or neglected," he adds.

Experts say there's no one-size-fits-all solution as each city faces unique challenges and factors such as geography, population and climate must be considered when designing effective responses.

India receives 80% of its annual rainfall during the monsoon season, which usually starts from June and continues until September.

The monsoon is crucial for agriculture and the livelihoods of millions of Indian farmers. They rely on seasonal showers in parts of the country where proper irrigation channels are absent.

But experts say climate change has made erratic weather - such as unseasonal rains, flash floods and droughts linked to extreme heat - a more regular phenomenon, directly affecting millions of people.

This year the monsoon arrived a week early in parts of southern India, catching authorities unprepared.

"A depression developed over the eastern central Arabian Sea which was instrumental in pulling up the monsoon current," says Mahesh Palawat, vice-president of meteorology and climate change at weather forecasting company Skymet.

In Delhi, the Minto bridge has become a symbol of the city's annual monsoon chaos. Almost every year, after heavy rain, a bus or lorry gets stuck under the bridge - an image that highlights the city's struggle with urban flooding.

This year, Delhi recorded its wettest May since 1901, with more than 185mm of rainfall, according to the Indian weather department.

Many residents reported damage to their property.

At least four people were killed and dozens more were injured in one of the two heavy storms that hit the city in May, according to media reports.

Meanwhile, in Bengaluru, more than 2,000kms (1,240 miles) from the capital, the problem looks different but its root cause is the same.

Once known for its network of lakes that helped manage excess rainwater, Bengaluru has seen many of these water bodies encroached upon. In their place now stand apartment complexes, business hubs and roads - leaving the city vulnerable to flooding.

Residents were evacuated after heavy rains triggered floods in Bengaluru in May

"Bengaluru is made up of three major valleys through which water naturally flows. Most of the city's lakes are located in these valleys," explains Ram Prasad, a lake conservation activist.

These valleys were originally designated as no-construction zones but over the years, encroachment has taken place and later changes in the law permitted infrastructure projects to be built in the area, he says.

"When you convert lakes - which traditionally act as flood buffers - into built-up areas, the water has nowhere to go. So, what we're seeing in Bengaluru today is the result of poor urban planning."

Mr Prasad points out that Bengaluru, which sits atop a hill, was never meant to flood and the current situation is entirely man-made.

Violations of building norms, especially construction that narrows stormwater drains or builds directly over them, have only made things worse, he says.

Meanwhile, Mumbai faces natural challenges due to its geography. For example, many parts of Mumbai are low-lying and close to the sea, which makes them more vulnerable to flooding during heavy rains and high tides.

But experts say it's human actions that have made things much worse: cutting down mangroves, which normally act like natural barriers against floods, and building on floodplains where water is supposed to drain.

"The breakdown is systemic - it begins with planning that often doesn't account for future climate variabilities, gets exacerbated by poor execution and is compounded by weak enforcement of regulations," Mr Kukerja says. "Political will is often reactive - responding to disasters rather than investing in long-term resilience."

This isn't just a big city problem. Smaller towns often suffer equally, if not more.

Over the weekend, at least 30 people died in India's northeastern states after heavy rains triggered flooding and landslides. Tens of thousands have been affected, with rescue efforts under way.

So, can anything be done to prevent this?

"Yes," says Mr Kukreja, but only if it is part of a long-term, co-ordinated strategy.

He suggests using mapping and real-time sensors to identify high-risk zones and alert communities. Predictive models can also help authorities plan better responses.

"But technology alone is not a fix, it needs to be paired with responsive governance and community involvement," he said.

For India's cities to withstand the rains, they need more than just de-watering pumps and quick fixes. They need forward-thinking planning, before the damage is done.

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