Brazil’s largest city launches project to clean up its waterways

World Today

Latin America’s rivers are some of the most polluted in the world. The World Bank says 70 percent of the region’s wastewater goes untreated.

In Brazil, sewage from millions of Sao Paulo residents is dumped directly into the Tiete river. But a major expansion of the sewer system is now underway.

CGTN’s Paulo Cabral has details.

The Tietê is São Paulo’s main river but it’s far from a picturesque tourist draw. The waterway is little more than a huge open sewer –biologically dead with the fish long gone. The water is polluted to the point of having nearly zero oxygen.

People used to seeing and smelling the poisonous Tietê River in São Paulo may be amazed to realize that a short drive upriver is enough to drink pure, fresh water directly from the Tietê source. And it’s really good. These springs were discovered and officially declared the source of the Tietê River in 1954. Later, the area was made into a state park. Drinking and taking home samples of the water is a must for most visitors.

“It’s a very interesting experience that everyone should try,” said actress Luana Romin. “It’s about returning to our roots, to nature. I was amazed to see all the life in the water — the little fish, the tadpoles.”

After this stream, which flows at about one and a half liters per second, leaves the source, it gathers strength and volume as it cascades down the mountains of the Serra do Mar and remains clean for about 70 kilometers. Until it reaches the metropolitan area of São Paulo, with its more than 20 million inhabitants. When their waste is dumped into the river, the Tiete is overwhelmed.

Now, a tunnel more than seven kilometers long is under construction alongside the Tietê to intercept much of that sewage and take it to a treatment plant. At its widest, the tunnel is almost three and a half meters high. It can handle up to six thousand liters of sewage per second. But the president of São Paulo’s Water and Sewage utility acknowledges that, even after the tunnel’s completion, a lot of sewage will still go untreated.

“The Metropolitan region of São Paulo has a lot of informal settlements,” said Benedito Braga, utility president. “About three million people live in these conditions. We need the population to help us in getting connected to the sewage collection systems.”

The crystal clear springs that feed the Tietê River serve as a reminder that there’s hope for even the dirtiest rivers. Managing this important resource so it can serve more people for longer is an ongoing challenge.