SAO PAULO, BRAZIL — ON a Saturday two weeks ago, like every day, the mucky Tiet^e River slogged through this megalopolis of 14 million people. But that day, at the lush green Ibirapuera Park - a safe distance from the river's fetid odor - about 2,000 children and adults sang songs, dressed as wild animals, rode in a colorful hot air balloon, and signed petitions to begin saving the polluted waterway.
The ``Thirsty Tiet^e River'' campaign, begun by a local radio station last August, is part of growing evidence, at last, that Brazilians are waking up to their environmental needs and problems.
``There is an ecological consciousness in Brazil,'' says Joao Mesquita, executive director of Radio Eldorado, ``but no one had ever thought of the Tiet^e. People are always talking about the Amazon, and about the [disappearing] Atlantic forest, but we didn't remember the river. It was right under our noses.''
The campaign has stirred many memories and hearts. ``People used to swim in the river, and there were rowing races. One man came to the radio station to show us his medal,'' Mr. Mesquita says.
Inspired by Britain's success in cleaning up the Thames, the Tiet^e campaign is collecting signatures on petitions to be presented to state and city officials. The rally was the first of several planned events that have begun to mobilize Paulistas.
Unless pushed, says Edson Secund'ario Leite, a building materials salesman, ``government won't do anything [about the river] because this doesn't get votes.'' Seated on a bicycle he has ridden three miles to the park, he adds, ``officials are elected to four-year terms, and the cleanup will take 10 to 20 years.''
Most of Brazil's economic development, and the pollution it caused, took place from 1964 to 1985, when a military government was in power. During that time, officials believed that progress was necessary at any cost. Industry grew and people flocked to the cities for jobs, but little was done to treat industrial waste and sewage. Today, Sao Paulo state accounts for half the country's income of about $350 billion, but less than half of the capital's residents are linked up to the sewer system and even most of that waste goes into the Tiet^e.
Human waste accounts for about two-thirds of the river's pollution, while industrial effluent makes up the rest. Specialists estimate that $2 billion is needed to clean up the Tiet^e, in part to pay for three new treatment plants. The Sao Paulo State Industrial Federation has pledged to help map industrial pollution sources. The city is negotiating a $500 million loan from the World Bank to dredge the river and other local polluted waters.
The Tiet^e crosses Brazil's largest city and goes on through the state of Sao Paulo, collecting and delivering pollution on its 600-mile route. In Salto, a city of 90,000 inhabitants just 63 miles from the capital, a concrete slide and diving board bear witness to a cleaner past. Today, says the city's culture, sports, and tourist secretary, Jos'e Geraldo Garcia, the river is covered by a foul-smelling foam and no one goes near it.
``We have lots of beautiful spots in Salto. Our city should be a resort, but the river has made this impossible,'' he laments. Mr. Garcia and a small group of townspeople have come to the rally to protest to Sao Paulo Mayor Luiza Erundina. They are speaking out against a provision in the state's new constitution allowing the capital to send more of its pollution their way, two years from now.
The job these Brazilians have taken on is a huge one. But, officials and activists say, the idea is to start somewhere.
``Consciousness has grown a lot,'' says Germano Seara, coordinator of a Sao Paulo state environmental education program. ``People don't have all the information on the relationships within an environment, such as how the food chain works ... but they realize there's a problem.''