Waste not, want not: Fish-farming in Calcutta

Before I joined the fishermen's co-operative, explained Niranta Makal, a thin, swarthy character of nervous disposition, 'I was a robber, a bag-snatcher. I used to hang around with a gang and we'd rob people in the docks.'

There were two reasons why Niranta abandoned the life of crime. For one thing, he was shot at by the police; for another, he could see that the 430 members of the Mudialy Fishermen's Co-operative Society were making a far better living than he was. He is now one of several dozen reformed criminals whose livelihoods revolve around a small wetland at the heart of Calcutta's docks.

Kiplings City of Dreadful Night where the cholera, the cyclone, and the crow come and go, by the sewerage rendered foetid, by the sewer made impure' - is witnessing a remarkable story of transformation, not just of criminals into honest men, but of paupers into well-shod producers, of human waste into fish - and without a penny of official aid.

Every day, an hour before dawn, a score of Niranta's colleagues make their way down to the Mudialy wetland. By the time the rising sun casts a burnished glaze over the shallow ponds, they have netted a ton of fish, fattened in waters nutritionally charged with human sewage. Soon the merchants appear, their vans clattering along pot-holed streets with names like Karl Marx Sarani and Oil Installation Road. Around 7am the catch is auctioned off and the fishermen head home for breakfast.

Shambhu Mondal, the co-operative's chairman, came here as a child when six fishing families, refugees from a dried-up river, decided to try their luck in the dockland marshes. 'In those days, the men barely caught enough fish to live off,' he recalled. Over the years much of the marshland was drained to make way for factories, but the fishermen gradually increased their catch. 'In 1980 we caught just over a ton a week,' said Shambhu. 'Now we get that much in a day.'

The rising yield is a reflection of the fishermen's hard work and the expertise of a government ecologist who has helped to refine the process of turning waste into edible protein. Every day 23 million litres of polluted water - a cocktail of industrial effluent and sewage - enters a square tank at one end of the wetland. 'In this one,' explained Shambhu as we peered into the pungent sludge, 'there's no oxygen at all, it's absolutely lifeless, but by the time the water is discharged back into the River Hooghly it's almost drinkable.' And it supports more than 40 species of fish.

The cleansing process, as Shambhu explains, employs peasant technology at its most ingenious: 'Nature has given us the means to purify water and that's what we do here.' Water hyacinth leaches out heavy metals such as cadmium, while other plants absorb grease and oil. The water reaching the main ponds is devoid of industrial pollutants but rich in nutrients - the sustenance for the algae and plankton which are devoured by the fish.

Since 1986 the fish catch has trebled and the co-operative's earnings have quadrupled. A decade ago, only a fifth of the members' children went to school; most were sent out to work or scavenge. Now, fishing profits pay for the education of all the members' children, as well as for medical care, funerals and religious festivals.

Profits also provide interest-free loans to members who wish to build new homes. 'When I joined the co-op in 1961,' said its accountant, Astam Kumar Bag, 'our living conditions were dreadful. I lived in a one-room mud hut and couldn't afford to eat much.' Now he has a three-room house with a pleasant garden. His children eat three decent meals a day, with fish every lunch.

The Mudialy fishermen are practising on a small scale what 20,000 people living on the other side of the city, in the East Calcutta Marshes, have been doing for almost a century. Each day they transform a third of the city's sewage into 20 tons of fish and 150 tons of vegetables. It is not only the most efficient and productive system of sewage treatment in the world, it is also the cheapest. It works so well that the mechanical sewage works built by the British in 1943 proved superfluous and ceased operating two years later.

But the East Calcutta Marshes operation is not one that can be easily replicated. It is a mature system of great complexity, involving a variety of people and practices over a wide area. Mudialy is different: recent in origin, compact, scientifically refined and eminently replicable. The success of the Mudialy fishermen has encouraged Calcutta's municipal authorities to establish several other low-cost sanitation schemes run on similar lines. 'It is a system of genius,' one official told me. 'The two basic requirements seem to be poverty and sunshine, and we have plenty of both.'

The significance of this story goes far beyond Calcutta and the business of turning waste into food. The Mudialy co-operative is just one example of how poor people across the world are making intelligent and sustainable use of the resources around them - waste, water, forests.

In the Philippines there is an impoverished fishing community which is restoring damaged coral reefs and protecting the inland waters from pirates and illegal trawlers. In Costa Rica a group of peasants, unlike the big banana and logging companies, has found ways of making a sustainable living from the tropical forests. In Mauritania, nomads are working out ways of sharing and conserving the sparse desert pastures.

In each case a group of people - ranging from a few families to many thousands - has taken control of local resources and democratically worked out how to make the best use of them. Many are notably entrepreneurial, and they are proving that good ecology and good economics often go hand in hand.

Unlike the Mudialy co-operative, most of these groups have received some financial and technical help. Oxfam is working with the Filipino fishing villages and a US charity with the Costa Rican peasants. One would expect non-governmental organisations such as these to support community initiatives; more significant is the fact that the World Bank is working with the Mauritanian nomads; that the EU has contributed to one Ugandan community development project; that the British government has helped to finance a community-based wildlife resources venture in Zimbabwe and a conservation project in Nepal.

This approach is long-overdue. The giving of small amounts of aid, sensitively targeted to communities that have the right, and the desire, to manage the resources on which they depend, will usually prove far more efficacious than the funding of grandiose projects which often do little more than gild the pockets of engineers, politicians and self-proclaimed 'development experts'. In their small way, the Mudialy fishermen, and thousands like them, are part of the process by which governments and aid agencies are reassessing where and how they invest.

'The Wealth of Communities' by Charlie Pye-Smith, Grazia Borrini Feyerabend and Richard Sandbrook is published on 30 June by Earthscan at pounds 10.95 (paperback).