The city that takes pride in showing daily resilience for coping with infrastructural breakdown, the monsoon of August 2025 brought Karachi to a total standstill. In less than 48 hours, rainwater collecting on the roads turned into torrents; intersections became lakes, terminals became islands, and neighbourhoods were divided by brown-coloured, fast-moving water. Authorities declared a public holiday, emergency services were activated across districts, and residents tracked the rain on their phones until phone signals vanished and the power went out.

By evening, officials and newsrooms were counting the human lives lost by drowning, electrocution, building collapses, and road accidents. The total rainfall recorded in parts of the city was the highest since the late 1970s. Across Pakistan, the monsoon death toll, swollen by flash floods in the northern region, rose into the hundreds.

This was not an isolated incident in Karachi. It was a national one. Monsoon rain sank southern Sindh, triggered mud-and-boulder torrents in Khyber-Pakhtunkhwa and Gilgit-Baltistan, severed roads, and forced rescue operations where rivers surged with frightening speed. The National Disaster Management Authority (NDMA) and meteorological offices have warned of more rain spells sweeping Sindh, including Karachi, Hyderabad, Thatta, Badin, Mirpurkhas, and Sukkur, throughout the coming weeks, with isolated heavy rainfall that could translate on the ground to another night of pumping water out of living rooms.

“Twenty years ago, when Karachi was a much smaller city, people assumed that whenever it rained, it rained everywhere. In reality, rainfall was always scattered, but since the city was limited to areas like PECHS, KDA, Gulshan-e-Iqbal, and North Nazimabad, nobody noticed the difference,” said environmentalist Tofiq Pasha Mooraj. He added that today, with Karachi’s massive expansion, we see a more obvious pattern: sometimes Malir is drenched while other neighbourhoods stay completely dry. These localised showers have been common for the past decade or so.

A city that flooded unevenly

Karachi’s flooding did not arrive evenly. Residents in Gulshan, Surjani, New Karachi, and parts of the northeast found themselves submerged waist-deep, while other localities rode out squalls in ankle-deep flooding. Near Jinnah International Airport, gauges logged 163.5 mm, reportedly the highest there since 1979, while northeast Karachi hit 178 mm, a five-year record for that monitoring point. In other pockets, totals ranged from 80 to 145 mm, still enough to overwhelm drains designed for far smaller, shorter bursts.

This pattern of one inundated neighbourhood, with the next merely drenched, poses an uncomfortable question: why does the same storm punish some areas and spare others? The answer lies in a tangle of meteorology, topography, and urban form.

“There are two very clear reasons why Karachi sinks every monsoon, and both have to do with how the city is governed and built,” said Farhan Anwar, an urban planner. The first is that any city in the world, whether it is New York, Mumbai, Bangkok, or Dhaka will experience flooding when rainfall of this magnitude occurs. Roads get submerged, underpasses fill up, and low-lying pockets are cut off. But in those cities, the water finds its way out within hours because there are stormwater drainage systems, pumping stations, and emergency protocols designed for such events. “Karachi, on the other hand, is left paralyzed for days because the fundamental skeleton of infrastructure is missing. Water does eventually recede here too, but only after causing devastation, and people losing their homes, livelihoods, and sometimes even their lives,” he explained, adding that what should have been a temporary inconvenience becomes a disaster because our systems cannot cope.

The second reason is structural because Karachi has grown at a pace that its infrastructure can never match. “This city was gifted with a natural drainage system in the form of the Lyari and Malir rivers, supported by smaller nullahs like Orangi, Gujjar, and dozens of other tributaries. If these channels had been respected, protected, and regularly cleaned, monsoon rains would not be the nightmare they are today,” Anwar explained. Instead, they have been narrowed by encroachments, blocked with garbage and sewage connections, and in many cases, turned into dumping grounds. These drains were the city’s defense system, but today they are treated like open sewers.

What turned heavy rain into a disaster

A century of poor decision-making set the stage for this flood. Karachi grew by straightening, narrowing, roofing over, or building into channels that once carried monsoon water out to sea. From Gujjar and Orangi Nullahs to dozens of feeder streams, natural drainage space has been pinched. Even when channels exist on maps, functional widths on the ground are reduced by siltation, encroachments, utilities, and ad hoc crossings, so a design storm no longer fits in the real canal. Research over the past decade has repeatedly linked Karachi’s urban flooding to the loss or obstruction of natural streams and the cumulative hardening of catchments.

Municipal drainage networks were not designed for the intensity and duration witnessed this week. Local media, citing utility managers, noted that portions of the city’s power and drainage infrastructure are rated for roughly 40 mm events, enough for fleeting downpours, not for hours-long tropical deluges that deliver 100 to 170+ mm in a day. Once system thresholds are crossed, the flow backs up, manholes geyser, and water seeks the old paths through homes.

It is also important to understand that thousands of people live along the banks of these nullahs, often because they have no other affordable housing option. Every time demolitions are carried out, the poor are displaced without viable alternatives. “If the government is serious about solving flooding, it must offer dignified relocation, low-cost housing schemes, affordable apartments, or regularised settlements with proper services rather than pushing people further into vulnerability,” the urban planner suggested, adding that the city cannot be made climate-resilient while its poorest residents are treated as disposable.

Even a well-designed network fails if inlets are clogged with trash, silt, or construction debris. Karachi’s storm seasons often begin before pre-monsoon cleaning is complete, or after new obstructions have formed. Where desilting and widening have been attempted most visibly along stretches of Gujjar and Orangi Nullahs, the benefits can be undone downstream when bottlenecks persist, or upstream when feeder drains remain choked. Projects launched after earlier floods improved segments but left the system vulnerable to backflow and choke points.

High-rise clusters and dense neighborhoods don’t create a storm, but they change how rain behaves once it hits the ground and how air moves around the city. Towers and walls can channel wind and rain, funneling surface flow toward low points. Large podiums, parking slabs, and tightly packed streets reduce permeable area – even when there are setbacks, many are paved. As a result, runoff spikes quickly and dramatically. Over-hours rainfall that might have infiltrated into soils decades ago now becomes sheet flow seeking the nearest sag. Studies and planning critiques of Karachi’s last two decades point to a rapid hardening of surfaces and the building over of micro-drainage that amplified flood peaks.

Another major factor is the way Karachi has been concretised over the past three decades. We have cut down trees, eaten up parks, and erased open spaces that once allowed rainwater to infiltrate into the ground. “Our infiltration basins have been destroyed brick by brick, replaced by asphalt, concrete plazas, and high-rises. Each new housing scheme is another nail in the coffin, with barely any thought given to stormwater management,” said Anwar. Even when new roads are constructed, they come without proper drainage channels. The result is a city that sheds water faster than it can absorb it, creating instant flash floods every time it rains.

Are crowded neighbourhoods to blame?

It is tempting to assume that high-rises and crowded localities cause more rainfall. However, the relationship is more nuanced. Density can shape the storm’s expression over the city and worsen flooding once rain falls, but it is not the primary tap that turns the sky on. The Pakistan Meteorological Department (PMD) advisories for this week highlighted synoptic setups affecting the entire Sindh belt, not just Karachi’s skyscraper districts.

Mooraj further noted the unpredictability of today’s climate, “Rising sea levels and altered wind currents have disrupted the balance. Rainfall patterns are changing and becoming harder to forecast. Many times, clouds simply blow away before releasing water.” These are signs of broader climate shifts like glacier lakes bursting, unusual snowfalls, flash floods, and droughts. “Such events have always occurred, but now they are more frequent, more intense, and more devastating,” explained the environmentalist.

Why do certain localities flood again and again?

Where storm drains pass under roads or rail lines, they are sometimes too small or partially clogged. A city can dredge a nullah for kilometres and still be undone by a single undersized throat. When heavy rain coincides with elevated tides or onshore winds, outfalls discharge less efficiently and water piles up inland. Service lines laid across channels, unplanned ramps, and rubble piles all nick away at capacity until the channel is functionally narrower.

Karachi’s 2020–2023 efforts to widen sections of Gujjar and Orangi and to clear thousands of dwellings from embankments did reduce choke points in places. But without comprehensive, end-to-end capacity upgrades, maintenance regimes, and protected buffers, each widened reach simply pushes the problem to the next constriction.

“Green cover also makes a difference. Areas with more trees and open spaces tend to attract and retain rain, while concrete-heavy neighbourhoods do not,” Mooraj said. He also added that wind direction and geography shape our weather. In summer, rain clouds usually come from the east through Nooriabad, reaching Malir first. In winter, systems arrive from Balochistan, often bringing stormy downpours. Sometimes we even witness ‘return rains,’ when clouds pass over the city, circle back, and pour down later.

What must change before the next cloudburst?

Drainage and pumping standards should be revisited to 21st-century extremes. When gauges in multiple Karachi localities report 140 to 180 mm in a day, a system designed for 40 mm will fail predictably. A tiered standard primary drains, sized for rarer, larger events; secondary networks for frequent ones can better match reality. The city’s own experience this week is the case study.

Karachi needs more room for water to be preserved in floodways, expanded detention basins, and along nullahs. Globally, nature-based solutions are sought increasingly that pair engineered channels with wetlands, bioswales, and permeable landscapes, especially in deltas and coastal megacities. In Karachi’s context, this means legal protection for drain reservations, engineered floodplains where feasible, and incentivizing green roofs and permeable courtyards at the building level.

“We must stop telling ourselves that money is the problem. It is not. After the 18th Amendment, provinces received significant funds from the federal pool. Karachi’s crisis is not financial; it is a crisis of political will, governance, and institutional capacity,” he said. The Karachi Metropolitan Corporation today has been reduced to little more than a registrar of birth and death certificates. At the union council level, there is no meaningful authority to manage drainage, waste, or flood planning. For decades rains have come and gone, yet nothing has been learned and no planning has been put in place. Contrast this with cities like New York, where every major disaster becomes an opportunity to build better, stronger infrastructure. Karachi, in comparison, simply waits for the next monsoon, pretending that each year’s devastation was unavoidable.

“All of this is ultimately human-driven. Our unchecked urbanisation, loss of green spaces, and global environmental damage have made extreme weather the new normal,” said Mooraj. He warned that Karachi must prepare for heavier downpours, longer dry spells, and rising seas. Unless we act now, flooding will not remain just an inconvenience, it will become a permanent crisis.

What this week taught us

The monsoon is not an anomaly in Pakistan – it is a season. In the north, the lesson is brutally simple: do not build in the way of torrents. In the south, the lesson is humbler but no less grave: it says give the water room, keep the exits open, and expect that tomorrow’s cloudburst will be stronger than yesterday’s. Karachi cannot change the monsoon’s path, but it can change how ready it is when the clouds arrive.

What Karachi needs is nothing less than a complete architectural and governance rethink. This has to begin at the grassroots level with empowered local councils, with citywide drainage master plans, with regulations that prioritise green and open spaces, and with strong accountability for agencies that fail to act.