The rain begins, and for many cities, so does the chaos. Choked roads, submerged streets, endless traffic — a familiar monsoon story. If you’re indoors, you may enjoy the patter on your window. But step outside, and it’s a different world: stalled vehicles, knee-deep water, and helplessness. Year after year, the same scenes play out. Why does waterlogging seem like an annual inevitability? Is the rainfall too much to handle, or are our cities simply built to fail when it comes to draining water?
For centuries, nature provided its own sophisticated flood defence system: vast networks of wetlands acted as giant sponges, lakes and ponds stored excess rainfall, meandering rivers had floodplains designed to swell and recede, and miles of open soil allowed water to simply soak into the ground. These were our cities’ natural allies against the monsoon’s might.
A woman vendor sits in her shop cart, as streets are flooded after torrential rains, in Ahmedabad.
| Photo Credit:
AMIT DAVE
However, in our rush toward rapid urban development, we have systematically ignored, encroached upon, and often destroyed our cities’ natural drainage systems. Across urban India — from Delhi to Mumbai, Chennai to Guwahati — lakes have been filled, wetlands drained, and riverbeds built over. Green, open land has been replaced by concrete and asphalt, turning once-absorbent cities into impermeable surfaces. So when heavy rains arrive, there’s simply nowhere for the water to go, and our streets turn into rivers within minutes.
People push an e-rickshaw through a severely waterlogged road following heavy rainfall, in Mathura.
| Photo Credit:
ANI
When cities turn into swamps
Just last week, Pune witnessed one of its worst spells of urban flooding, with roads turning into rivers and traffic crawling through waist-deep water. The Pimpri-Chinchwad area was particularly hard-hit, with shocking visuals circulating online — vehicles stranded, people wading through murky water, and entire stretches submerged. These scenes once again highlighted the city’s fragile drainage infrastructure, worsened by rapid urbanisation, disappearing natural water channels, and poorly planned construction.
Commuters wade through a waterlogged road amid heavy rains as unseasonal rains lash several parts of Mumbai, at Andheri in Mumbai.
| Photo Credit:
ANI
Chennai, too, offers a deja vu. Despite being no stranger to floods, the city continues to grapple with waterlogging every monsoon. With wetlands shrinking and stormwater drains often clogged or overwhelmed, even moderate rainfall is enough to throw daily life out of gear.
Bengaluru recently joined the list of urban deluges. In mid-May, the city recorded over 105mm of rain in 24 hours — one of the highest in 15 years — and saw 130 mm in a single night thereafter. Experts link these recurrent floods to Bangalore’s transformation: over 190 lakes once interconnected, now encroached upon or polluted, and stormwater drains blocked by unplanned construction.
What went wrong: From water-wise to water-wrecked
Indian cities weren’t always so flood-prone. They were once built in harmony with water channels, not against them. Lakes, wetlands, canals, and floodplains formed nature’s built-in flood defence system. Wetlands like Chennai’s Pallikaranai marsh and Pune’s Pashan Lake absorbed rainfall, chains of interconnected lakes stored storm water, and open land let water seep into the ground, recharging aquifers.
A view of the Pallikaranai Marshland in Chennai.
| Photo Credit:
PICHUMANI K
But in the race for unchecked urbanisation, we’ve systematically destroyed this balance. Wetlands have been drained, lakes filled, riverbeds narrowed, and floodplains built over. Hills have been flattened and slopes ignored, all to make way for concrete jungles that repel, rather than absorb, water. Today, impermeable surfaces have replaced open soil — parks, sidewalks, and even courtyards are paved. So when it rains, water can no longer seep into the ground. Instead, it pools on the surface, quickly turning roads into rivers.
To make matters worse, our stormwater drainage systems are often outdated, clogged, or designed for an era of less runoff. In many places, the same drains carry both sewage and rainwater, leading to overflows and sanitation crises.
Urban planning itself is part of the problem — Many cities follow “copy-paste” urban designs — lifting layouts suited to dry regions or foreign contexts, without considering local topography or natural water flow. This means that hills are flattened, slopes ignored, and construction continues on land that was never meant to hold buildings, but water.
Where does the water go now?
The direct consequence? When it rains — and it now rains harder and more frequently due to changing climate patterns — the water has nowhere to go. The natural systems that once stored or absorbed it are gone. What remains are choked storm drains, overwhelmed sewage lines, and flooded streets.
So even a short spell of rain can now bring an entire city to a standstill. Not because of the rain itself, but because the places built to handle it have been buried beneath the very concrete that now drowns us.
When cities can’t breathe: The forgotten science of urban hydrology
Urban hydrology is the science of how water behaves in a city — how it falls, flows, seeps into the ground (infiltration), and gets stored or drained. In a well-planned city, some water soaks into the soil, some gathers in lakes and wetlands, and the rest flows through stormwater drains.
Think of it like a sponge: absorb, store, release.
But today’s cities act more like plastic sheets. Concrete, asphalt, and tiles cover the ground. There’s no soil left to absorb rain. So, when it pours, almost 90% of the rain becomes run-off, rushing over hard surfaces with nowhere to go.
A simple diagram to show the various parts and functions of a Rooftop rainwater harvesting system.
Why it fails: From overflowing drains to flash floods
Most urban drainage systems were built for smaller cities and gentler showers. Now, with dense construction and fewer green zones, they get overwhelmed within minutes.
This leads to:
Flash floods: Streets and underpasses flood fast, often within minutes of heavy rain.
Waterlogging: Roads turn to rivers, homes get flooded, traffic stalls.
Groundwater depletion: With infiltration blocked, cities lose out on natural groundwater recharge, down by 50–70% in some areas (Central Ground Water Board).
Health hazards: Overflowing drains often mix with sewage, triggering sanitation risks and disease outbreaks.
Science ignored
Urban hydrology could have helped us plan better — to live with water, not against it. But it was sidelined in the race for rapid construction. As a result, the water cycle in cities is broken, and every monsoon reminds us just how costly that ignorance is.
Lost wisdom, future solutions: Learning to live with water
Water-wise past, concrete present
Ancient India knew how to live with water. From stepwells and temple tanks in the south and west, to kuls in the Himalayas and johads in Rajasthan, traditional systems managed rain effectively — collecting, storing, and recharging groundwater. These weren’t just structures, but part of a larger water ethos: absorb, store, reuse.
At the heart of this wisdom was Rainwater Harvesting (RWH) — collecting rain where it falls and using it to recharge the earth. Its benefits were simple: less flooding, more groundwater, and lower dependency on municipal supplies.
The Highways Department has proposed to install such Rain Water Harvesting structures at over 200 places beneath the 10 km long JM Bakery – Airport flyover in Coimbatore.
| Photo Credit:
SIVA SARAVANAN S
But today, these systems are either forgotten or poorly maintained. Many buildings have token RWH setups that lie clogged, unused, or non-functional. Rooftops drain water into streets instead of recharge pits, and urban lakes have become landfills or parking lots.
Meanwhile, drainage and sewage often share space, leading to health risks when rains cause both to overflow.
The way forward: Building sponge cities
Urban flooding isn’t inevitable — it’s the result of poor design. The answer lies in transforming our cities from concrete slabs to porous landscapes that absorb water like sponges.
1. Blue-green infrastructure: Integrate blue elements (lakes, wetlands, channels) and green spaces (parks, green roofs, bioswales). Together, they slow and filter rain naturally.
2. Decentralised RWH: Every home, street, and complex must harvest rain through rooftop systems, recharge pits, and permeable courtyards — making water management a collective habit, not a government task.
3. Revive and Restore: Community-led restoration of lakes and stormwater channels has shown results.
Example: Jakkur Lake, Bengaluru – revived using treated water and wetlands, now recharges groundwater and prevents floods.
UK’s ICE (Institute of Civil Engineers) President Fr. Dr. Anusha Shah visited Jakkuru lake with Atkins team. On this occasion, Atkins, a leading international design consultancy firm, observed the process of lake revival and expressed appreciation for the sustainable technologies adopted by the corporation’s lake division in the lake revival efforts.
4. Enforce ecological limits: Strictly ban construction on floodplains, wetlands, and lakebeds. These are nature’s buffers — building over them invites disaster.
5. Climate-smart urban planning: Design for today’s rain, not yesterday’s climate. Cities need new flood maps, risk zones, and integrated water-smart plans.
Global Example: Room for the River, Netherlands – instead of resisting floods, it made space for them using multi-use flood zones.
A future that breathes with the rain
It’s time to reimagine how our cities handle water — not by draining faster, but by absorbing smarter. Rain isn’t the enemy. Poor planning is.
To flood-proof our future, cities must reconnect with water — not by pushing it away, but by giving it space, respect, and room to flow.
Cities like Indore and Hyderabad have taken early steps — reviving lakes and stepwells, introducing rain gardens in public spaces, and integrating rainwater harvesting systems into new housing layouts. These may seem like small wins, but they offer scalable, replicable models for water-smart urban planning.
