Sitting in their shiny glass towers, corporate financiers striking billion-dollar deals gaze daily on a jumbled sprawl of conjoining tin roofs and rubbish-strewn alleys that mark out Asia’s largest slum.

The unavoidable view of extreme poverty takes the shine off having a big corner office in Bombay’s answer to Canary Wharf.

If the state government’s ambition is realised, though, India’s banking fraternity will one day be happily overlooking an ordered scene of seven-storey apartment blocks, hospitals, schools, gardens, jogging tracks and even a golf driving range under a $2.3 billion (£1.2 billion) plan to demolish the shantytown.

Dharavi, home to an estimated 600,000 people and a hive of cottage industry, was put up for sale this week. Advertisements in newspapers, including The Wall Street Journal and the Financial Times, proclaimed the project as “the opportunity of the millennium” and a “perennial source of income”.

But as dissenters hang black flags from their ramshackle homes this weekend, warning of a “bloodbath” if they are forced out, the scheme is already taking shape as a perennial headache for any international developer despite the clear profit to be made.

Once unattractive marshland, Dharavi is now slap in the middle of India’s burgeoning commercial hub.

It exemplifies all that is wrong with infrastructure planning as poor migrants swarm to the cities seeking their slice of the economic boom. Its redevelopment will be a big logistical challenge.

“It represents literally the rebuilding of a town. It is like taking one tenth of London and just moving it,” Sheela Patel, director of the Society for the Promotion of Area Resource Centres, said.

The plan for the 356-acre site looks good on paper. An estimated 57,000 families – representing about half of Dharavi’s total population – living in the most unhygienic conditions will be rehoused free in 225 sq ft flats with running water and indoor lavatories. Roads will be built, alongside $445 million worth of public amenities.

There is said to be just one working lavatory in the whole of Dharavi. Excrement flows through the warren of dark alleys in drains loosely covered with ill-fitting flagstones or piles openly in rat-infested, littered scrubland where children play cricket with stones and plastic bottles.

Mukesh Mehta, the US-based architect driving the redevelopment, claims the area will be “a beautiful suburb” by 2014. It will also effectively extend an existing commercial zone, close to the airport, which houses the National Stock Exchange and leading banks including Deutsche, Citibank and JPMorgan.

The state government – long embarrassed by Dharavi as it promotes Bombay as a global financial centre – is seeking foreign developers prepared to share this vision.

At a cost of $2.3 billion, the project is not for cowboy builders. Bidding criteria exclude companies whose net worth is less than $700 million and whose annual turnover for the past three years was under $600 million.

The successful bidders, to be announced in September, must also have experience of developing seven million square feet in at least one 100-acre township.

The Government claims there is nearly $1 billion to be made. In one of the world’s most expensive property markets, where space is scarce due to the peninsula city’s geographical constraints, this is a tasty proposition.

Some residents are sold on the plan. Noor Ulla Hasan, 39, a taxi driver, who shares a 12ft by 10ft space with five relatives, said: “If the government puts up new buildings, we will live there.”

But most appear opposed to a proposal that largely ignores Dharavi’s unofficial $1 billion-a-year economy, fuelled by potteries, tanneries, bakeries, metal workshops and one of the most enterprising recycling operations anywhere in the world.

Slum dwellers, half of whom work from home on a range of jobs from tailoring to separating the plungers from plastic syringes, fear the loss of their livelihoods. Half of them will not even be eligible for rehabilitation, driving them into new slums.

Curing leather in a sweltering workshop for 300 rupees (£3.76) a day, Masood Ahmed, 37, said: “What’s the use of a new building if it hurts our employment?” Tara, a mother-of-three earning 50 rupees a day washing used cooking oil tins for recycling, said: “I want to stay here.”

Jockin Arputham, president of the National Slum Dwellers Federation, said: “At worst, 75 per cent are dead against this and will come out on to the streets. There is going to be a bloodbath because you are forcing people to agitate. Dharavi should not be touched by the international market.”

With resistant slum dwellers claiming lack of consultation and threatening civil unrest, a public-private partnership in a notoriously corrupt system may be too fraught with difficulties to attract serious international players.

“They would be crazy to bid,” Anirudh Paul, director of the Kamla Raheja School of Architecture, said. “It is very complex coming in from outside. There are too many questions unanswered.”

In the meantime, people like Mustak Mohammed Khinu, 24, who lives above his small general store, carry on regardless. “I don’t know what the government is going to do. They have not asked us,” he said.

Slum census

$1bn
Dharavi’s estimated turnover

17%
of India’s leather exports comes from Dharavi

1m
something like the true population of the shantytown

6m
slum dwellers in Bombay; 42 per cent have a living area less than 10 sq m

$40bn
required in next decade to upgrade Bombay’s infrastructure

60%
of global slum population found in Asia

Source: UNHabitat, NSDF, Indian Government, Times research

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