Associated Press

As the New York metropolitan region reels in the aftermath of Hurricane Sandy, those outside the area may wonder how their own cities would fare in such a disaster.

What if a storm on the scale of Sandy took place in another teeming metropolis surrounded by water – like, say, Mumbai?

First, some basic stats: Mumbai has 13 million residents to New York’s 8.2 million and is twice as densely populated, at 53,600 people per square mile, compared to New York’s 27,243 per square mile.

Mumbai was once an archipelago of seven islands that is now bound together by land reclaimed from the sea, and the city is surrounded by water on three sides. While heavy rainfall inundates the city each monsoon, submerging parts of the city and leaving commuters stranded, urban planners and architects say Mumbai is completely unequipped to deal with sudden flooding like the kind that accompanied Hurricane Sandy.

“Mumbai is a unique city that has grown, and continues to expand, without any physical planning in terms of land use or planning for emergencies and natural disasters,” said P.K. Das, an urban planner and architect who heads P.K. Das and Associates, a Mumbai architecture firm. Building codes that do exist are simplistic and only address structural stability in the case of a fire, he said.

Experts here fear a repeat of the events of July 26, 2005, when the city received a record 37 inches of rain in 24 hours. The deluge claimed the lives of 900 people and left thousands stranded as the city came to a standstill.

That day, “we saw firsthand the impact on the city and the lack of preparedness,” said Rohan Shivkumar, deputy director at Kamla Raheja Institute for Architecture and Environmental Studies. “While there were very few pre-emptive measures taken, the city was not even equipped for rescue operations,” he said.

Mumbai’s antiquated storm-water drainage system, which was initially put in place in the early 20th century during British rule, was largely blamed for the flooding. A plan submitted in 1993 to overhaul Mumbai’s storm water drainage was turned down by the municipal corporation because of a lack of funds.

In a report following the 2005 floods, the government of Maharashtra said that Mumbai needed to replace its drainage system, but it would cost 12 billion rupees, or $221 million. The city authorities drew up an extensive plan to overhaul the storm-water drainage system and develop the Mithi River to create outlets for water. Over seven years later, the city still remains ill-prepared, flood control projects are incomplete, and the estimated project cost has now gone up to 40 billion rupees, or $739 million.

While the mangroves, wetlands and waterways that surround Mumbai provide a natural defense against flooding, they are being slowly eroded to make room for new real estate development, making the city increasingly vulnerable. A study conducted by the Mumbai Transformation Support Unit found that over the last 40 years natural vegetation like mangroves and bodies of water like lakes and ponds have shrunk by 53 percent.

“Although there are rules and regulations in place that are supposed to protect the mangroves, with the sort of real estate pressure there is on the city, they are not systematically followed,” said Mr. Shivkumar. “No one really cares about a possible future disaster when there is money to be made currently.”

Construction along the shoreline is regulated by Coastal Regulation Zone guidelines that attempt to manage the density of development up to 500 meters (1,600 feet) from the shore. In January 2011, the government eased the restrictions on construction along Mumbai’s coastline to allow the redevelopment of fishing communities and industrial activities. However, architects say there is a lack of clarity in the application of the rules.

Building rules, in fact, are not applied consistently around the city. While newer buildings are not given permission to be built unless they follow regulations like fire safety, older buildings are poorly maintained and uninspected.

“In Mumbai, there are a huge number of properties in the city that are under rent control, which means that the landlords don’t do anything much for their upkeep,” Sameer Padora, an architect at Sameer Padora and Associates in Mumbai, said in a phone interview. “Buildings such as these collapse during a regular Mumbai monsoon, so if a cyclone of the scale of Sandy were to take place here, the damages would be staggering to say the least.”

Another worrying factor is the fact that over 60 percent of the city is dominated by informal settlements, often slums, where building regulations are not applied at all. “These are built edge to edge, so that if something happens to one of the structures, the damage spreads very quickly,” said Mr. Padora.

In narrow lanes, unregulated construction has made them even narrower, so access becomes an issue for fire or rescue operations, he said. These areas normally lack proper drainage, so water tends to accumulate in pockets as well.

For Mumbai, a lack of planning risks exacerbating the effect of natural calamities. Mr. Das, the architect, said the city did not have a comprehensive disaster plan in place and lacked alarm systems, early detection systems, evacuation plans or emergency shelters.

“We run this city on the principle of firefighting – if there is a disaster somewhere, we hurriedly intervene,” says Mr. Das. “Knee-jerk reactions do not constitute proper governance.”

There is a need to institutionalize disaster management, experts say, so that proper infrastructure is put in place and periodic checks are carried out to see if it is operable.

“Given that the city is quite low lying, if there was a rapid rise in sea level, then we would be flooded, much like what is happening in New York currently,” said Mustansir Dalvi, a professor at Sir J.J. College of Architecture in Mumbai. “The difference is that we might take longer to recover because they seem to have their systems in place.”