Development & Aid, Environment, Headlines, Latin America & the Caribbean

DEVELOPMENT-BRAZIL: Harnessing Rainwater, a Rural and Urban Solution

Mario Osava

RIO DE JANEIRO, Nov 25 2003 (IPS) - Rainwater catchment is providing solutions to chronic water shortages in two vastly different parts of Brazil: impoverished rural areas of the semi-arid northeast and the rich metropolitan region of Sao Paulo, Brazil’s biggest city.

The One Million Rural Water Tanks Programme (P1MC) was launched in 2001 to harness the potential of the sporadic rains that fall in northeastern Brazil, a region that suffers frequent droughts, in order to provide drinking water for five million people within the next five years.

The P1MC was awarded the prestigious ”Super Ecology Award 2002” last year by a Brazilian magazine, ”Superinteressante”, which described it as ”a definitive solution to the lack of drinking water” in the region.

The semi-arid drought-stricken tropics in Brazil’s northeast is a region of around one million sq kms which is home to some 15 million of Brazil’s approximately 177 million people.

The P1MC is carried out by the Semi-Arid Coordination Group (ASA), a coalition of 750 non-governmental organisations involved in development and protection of the environment, community associations, church groups, unions and federations of rural and urban workers, social movements, and public and private organs of international cooperation.

The idea is to build a rainwater catchment tank next to each home among the most impoverished rural population, which is scattered around the brushland.

In the northeast, it rains at least 200 mms even in the driest years, which would be enough to supply drinking water for a family of five if the water is collected from the rooftops and stored.

During the dry season, family members – usually the women – walk an average of an hour a day to the nearest waterhole. The waterholes, the only sources of water, are shared by livestock, and are germ-infested and make diarrhoea a fact of life in the area, where infant mortality rates are high.

Countless hours are lost in ”going back and forth, the bucket of water weighing down my arms, eating up my time, my strength and my youth, undermining our hopes,” Josefa Cabral do Nascimento, a 56-year-old widow, said in testimony gathered by ASA.

Cabral do Nascimento, one of the first beneficiaries of the programme, said she ”could not contain the flood of tears…of happiness, of new life,” when she saw the water tank that she had dreamt of for decades, finally built next to her home.

Prefabricated cement slabs facilitate construction of the round 16,000-litre concrete reservoirs, part of which fit into a 1.8 metre hole dug into the ground. The tanks are filled from spouts connected to gutters installed on both sides of the roof.

The water tanks are built by the residents themselves, with the help of local bricklayers who take a course provided by ASA member organisations to learn to build the cisterns, which cost just under 300 dollars each to build.

But it is not just a question of putting an end to the thirst, to intestinal parasites, or to the sacrifice made by women who must trek long distances to fetch brackish water from the waterholes, Joao Amorim, P1MC operations manager, said in an interview with IPS.

Only communities that organise themselves participate in the programme, one of whose main focuses is community organisation.

The beneficiaries must take a two-day course on how to take care of the cisterns, which involves keeping them shut tight, taking down the gutters and spouts and washing them in the dry season, discarding the first rainfall, which cleans off the rooftop, and treating the stored water with chlorine, to ensure that it is safe to drink.

The full name of P1MC, the ”Programme of Social Formation and Mobilisation for Living in Semi-Arid Regions – One Million Rural Water Tanks,” indicates the project’s broader aim: helping local communities learn better techniques for living in a semi-arid environment.

The programme had few funds in its test phase, enough to build just 5,000 water tanks. But it has now been incorporated into the social programmes of the leftist government of Luiz Inácio Lula da Silva, and has received funding from the Ministry of Food Security to build 12,000 more tanks in the immediate future, said Amorim.

P1MC also receives funding from the Environment Ministry and the United Nations children’s fund (UNICEF), as well as the international aid agencies participating in ASA.

Another 20,000 tanks will be funded by contributions from the Brazilian Federation of Banks.

The goal is to build 45,000 cisterns by mid-2004, and to accelerate the pace over the next few years as new public and private sector partners are drawn into the project, until one million tanks are built by 2008, said Amorim.

Water is also a problem in a radically different setting, the greater Sao Paulo in southeastern Brazil, the country’s ”economic capital.”

This year, less frequent than normal rainfall has aggravated longstanding water problems in the city, where water sources are polluted and have been affected by deforestation in surrounding areas.

The water and sanitation company of the state of Sao Paulo estimates that as it stands, the water pipe system will only be able to meet the needs of the metropolitan region, home to 17 million people, until 2010.

Unlike in the northeast, the problem in Sao Paulo is not one of scarce rainfall. In fact, the city, especially outlying slum areas, suffers frequent ”urban micro-floods” every summer caused by heavy rain.

Nevertheless, Sao Paulo residents are now facing the possibility of water rationing, a problem that could be at least partially alleviated by rainwater catchment systems.

Although the proportion of ”harvested” rainwater would be small in relation to the actual amount of rainfall, it could significantly ease the impact of the torrents of water that periodically flood parts of the city, Ivanildo Hespanhol, a professor at the Polytechnic School of the University of Sao Paulo, told IPS.

For years, local authorities have been digging large pools in the city to catch part of the rainwater runoff, to reduce the damages caused by the micro-floods.

Rainwater catchment systems could also be incorporated in buildings and houses, to provide water for household uses like cleaning, flushing toilets, and watering gardens and yards, said Hespanhol, who explained that rainwater in Sao Paulo was not suitable for drinking, due to the air pollution.

Some buildings in Sao Paulo have already begun to harness rainfall, in an effort to cut costs. Water is the second-biggest expense in the administration of apartment buildings, after the salaries paid to building employees. The city government provides incentives for such projects.

However, the initiatives carried out so far are not well-planned, because the installation of adequate rainwater catchment systems is an engineering question, said Hespanhol, an engineer who specialises in the treatment and reutilisation of water.

Rainwater collection and storage should be carried out directly on the rooftops by means of a system that channels the water down to special faucets, to avoid the expense of energy in pumping the water, he said. But that requires structural changes in buildings, and should ideally be incorporated during the construction process, he pointed out.

In addition, said Hespanhol, rainwater catchment, which is more viable in industries and other activities that occupy vast areas and use large amounts of water, should be combined with the treatment and reutilisation of sewage water.

In the future, different pipes will be needed for drinking water and water used for household, industrial and other purposes, said the engineer.