Dharavi, described as Asia's largest slum, is home to thousands of recyclers
By Shivani Dhillon
One Planet, BBC World Service
Mumbai, India's financial capital, is known as the city of dreams for most young Indians.
People from around the country come to the city to fulfil their dreams, but many of them end up in slums; it is estimated that more than half of the city's population live in squalor.
At the heart of the city - surrounded by posh, luxurious skyscrapers - is Asia's largest slum, Dharavi. It spreads over 525 acres (212 hectares) and is home to more than a million people.
Dharavi may seem like any other: full of dirt, filth and sewage, but what maybe an eyesore for most of the city's residents is also a recycling marvel.
"The majority of the place is a plastic recycling industry," says Naushad Khan, chairman of Dharavi Businessmen's Welfare Association.
The slum is home to thousands of small-scale recycling factories
"We also recycle paper and cardboard. If we make a brand new cardboard box the cost is about two dollars but if we reprocess the old one the cost is half."
It's an industry that employs almost 200,000 people.
Walking through Dharavi, home to an estimated 15,000 single room factories, it is difficult to find anything that is not recycled here.
The plastic, which comes in all forms, including bottles, boxes, pens, is first sorted according to colour and quality.
Next, the plastic is ground into flakes and sold to a granule maker. In his factory, the plastic flakes are washed, dried, melted, squeezed into wires and then chopped into pellets.
These pellets are then used to make different types of products.
Most of the waste is collected from various households and commercial buildings by housemaids and servants who then bring it to Dharavi for recycling.
Even the rag pickers roaming the streets of Mumbai help in collecting the waste.
As you walk along the dark alleys of Dharavi, you come across workshops and factories recycling everything from plastic and paper to soap and candles.
One such factory recycles vegetable oil tin cans that are used in every household in India. These two-litre containers are hammered back into shape, dipped in scalding water, cleaned and then polished.
"We make new cans out of old and used ones. We then sell them to oil companies and directly to local consumers as well," says Pannu Paswan, one of the factory's workers.
But this extraordinary way of recycling may soon come to an end. The government has provisionally approved a plan called "Vision Mumbai", which aims to create a world-class city by 2013.
Mumbai will have waste problems without recycling, say campaigners
Under the plan, Dharavi will be demolished and replaced with flats in high-rise blocks for the slum dwellers, and the rest of the land will be used for shopping malls and luxury apartments.
But there is fierce opposition to this plan from Dharavi residents who believe that this is only to benefit the rich and the powerful.
The man behind the Vision Mumbai scheme is Mukesh Mehta, an architect and urban designer. He says that there has been thorough consultation.
"We live in a democracy and slums are a big vote bank for the government," he explained.
"If there was no support for the redevelopment project, the government would never give the green signal," added Mr Mehta, who is also the adviser to the Maharashtra State government on the Dharavi Redevelopment Project.
Jockin Arputham, president of National Slum Dweller's Association, is fighting for the rights of the local residents. He is suspicious that it is all about money.
"Dharavi has become a goldmine sitting at the heart of Mumbai. It is not about the poor, it is only about minting money," he suggested.
Fears and suspicion
Dharavi residents are not against the redevelopment project, but they question the way Dharavi is being redeveloped.
Officials say slum dwellers will enjoy a better quality of life
The residents warn that if the area is redeveloped it will bring problems for not just them but every single resident of Mumbai.
"We bring the entire city's dirt and create a livelihood from it," says one resident.
"If Dharavi is redeveloped, all this waste will lie on the roads and eventually people living in expensive high-rise apartments will have to come down and face the filth."
But environmentalists believe that this is only a threat. They say that if Dharavi is redeveloped, the waste will not lie on the roads of Mumbai because there is a culture of recycling existing within every household.
"People from urban households sell paper and glass bottles to small traders who roam about on cycles," says Debi Goenka from Bombay Environmental Action Group.
"So, people actually earn money out of waste. Even if they throw it in the bin, it is picked up by their maids and servants who sell them to recycling units."
It is true that if Mumbai has to become India's Shanghai, it needs to improve its infrastructure and its image.
But in the process of improving that image it is the poor people, making a living literally out of rubbish, whose lives will change forever.
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