By Ishaan Tharoor

In Manila, millions of residents now live in a world of mud. Torrential rain over the weekend triggered the worst flooding the Philippines’ capital has seen in over four decades, submerging more than 80% of the city, killing at least 246 people and displacing hundreds of thousands more. By Tuesday, the water had receded in many places, but it left behind ruined homes and swept-away neighborhoods, and according to health officials, it disabled the majority of Manila’s medical facilities. Debris, sewage and abandoned vehicles that were tossed around by gushing currents now litter the notoriously polluted capital; aid workers warn of water-borne diseases. The government has placed the area around Manila under a “state of public calamity.”

In an appeal for assistance, Philippine President Gloria Macapagal-Arroyo described Tropical Storm Ketsana, which hit Manila on Sept. 26, as a “once-in-a-lifetime typhoon.” A month’s worth of rain deluged the city in the space of 12 hours. “The system is overwhelmed, local government units are overwhelmed,” said Anthony Golez of the state’s National Disaster Coordinating Council at a press conference on Sept. 28. (See pictures of the storm.)

Yet many in the country are pointing fingers at its politicians for failing to predict the scale of the disaster or lessen the damage it caused. Manila, they say, was always bound to face such catastrophe, and more should have been done to help its millions of residents prepare. A recently published study by the Economy and Environment Program for Southeast Asia (EEPSA), a research group based in Singapore, ranked metropolitan Manila as one of the provinces in Southeast Asia most vulnerable to flooding. The capital region is perched on a marshy isthmus that is crisscrossed with streams and rivers. An ever-growing population — Manila is now a sprawling mega-city of some 12 million people, larger still when factoring in the day-worker population — and the lack of infrastructure to accommodate it left swaths of the city exposed. “What we are seeing is a phenomenon that will affect many major cities in Asia,” says Neeraj Jain, country specialist for the Philippines at the Asian Development Bank (ADB), which is headquartered in Manila. “Urbanization has been so rapid, yet the planning processes have lagged.” (Read “Manila Through the Eyes of F. Sionil José.”)

Last weekend’s flood was in large part the result of the capital’s poor drainage and sanitation systems, which have been neglected by several successive administrations in power. As Ketsana rained down upon Manila, sewers that were clogged up by plastic bags and other refuse led to roads becoming rivers and gardens lagoons. Video images of desperate people riding floating pontoons of garbage down inundated streets were a sign not just of the consequences of the flood, but also its causes. Many impoverished Manila residents live in makeshift settlements by rivers and creeks — the source of their drinking water — that overflowed and carried off their homes. “People have always been living on the edge,” says Carlos Celdran, a popular Manila historian and performing artist. “It’s amazing the city has actually managed to make it this far.”

The Spanish seized Manila from its Muslim rulers in the 16th century and set it up as their colonial seat in Asia. The city was a flourishing, elegant entrepôt for centuries, but in recent times civic planning has been more haphazard as the population has boomed. Lambert Ramirez, executive director of the National Institute for Policy Studies, a Manila-based think tank, says much of the blame for poor urban management ought to be leveled at the government. “There’s no coordinated policy for cleaning up garbage. There’s no political will to get even simple things done,” he says. Ramirez spoke to TIME while salvaging appliances and valuables from his own flooded home. (See pictures of the recent floods in Georgia.)

Jain of the ADB says the leadership in Manila, faced with elections in the coming months, is indeed thinking of long-term solutions to its infrastructure woes. Plans have been afoot to improve sanitation and also relieve the population burden in metro Manila by shifting certain businesses and government offices to areas outside the dense capital region. But the challenge facing the Philippines and other poor Asian countries is one of resources. Most Southeast Asia nations budget around 2% or 3% of their GDP for infrastructure development. To fend off such disasters in the future, Jain says that figure ought to be closer to 5% or 6%. It’s a deficit that few governments can afford to make up overnight.

But given the looming specter of climate change, they may have to find a way sooner rather than later. The prospect of another typhoon this week underscores environmentalists’ concern that shifts in global temperatures may mean increasingly extreme weather patterns for coastal cities like Manila. “[Ketsana] was a startling, unique event,” says Herminia Francisco of the EEPSA in Singapore. “But then I think this is going to happen more and more frequently in the future.” (See a TIME graphic on destructive weather.)

For today, as international aid pours in from organizations like the Red Cross and the World Food Program, Manila residents are slowly retrieving their homes and livelihoods from the mud. Thousands of volunteers have donated food and rushed to help those who were worse affected. “Filipinos are used to crisis,” says Celdran. “We’ve gone through a lot over the years, but we’ve managed. We’re a resilient people.”