Guanabara Bay 'jumps the queue' and sees a new promise of depollution

One day after moving to your home in Vigário Geral, 20 years ago , retired Reinaldo de Almeida, 76, saw his door flooded with water mixed with sewage after heavy rain in the northern part of Rio de Janeiro.

The reason was common to many residents of the metropolitan region: waste thrown into the rainwater network, made to collect rainwater, which ends up overflowing polluted in storms.

The construction of a sewer system nine years ago in part of the neighborhood did not solve the retiree’s problem. The pipes often clog, causing overflows of polluted water, which runs down the street to the rain channel whose destination is the Pavuna River, a tributary of the Guanabara Bay.

Like Almeida, more from half of the approximately 9 million inhabitants around the bay do not have treated sewage. It is a chronic problem whose solution promises add up to almost 76 years.

Almeida and her neighbors they also symbolize the main failure of the projects that promised to clean up the bay. They are next to the Pavuna ETE (sewage treatment plant), but they are unable to properly send their waste there.

The Guanabara Bay Depollution Program, from 1994, built four treatment plants, but not all the pipes needed to carry the waste to them. What has been installed suffers from maintenance failures. ETE Pavuna operates with only 15% of its capacity.

The failure pushed to the Olympics of 2015 the promise to treat 76% of the sewage released into the bay. Five years later, the rate varies from 20% to 40%, depending on the data source.

The basic sanitation concession in Rio, concluded in April, renewed the promises. The new target is to treat 99% up to 2033, in line with the new regulatory framework for the sector.

An emergency investment of R$ 2.7 billion over the next five years by the concessionaire Águas do Rio, winner of the auction in the region, is expected to accelerate the end of the disposal of waste in the bay.

For this, however, the definitive solution was postponed for those who do not have a sewage system in eight municipalities of the hydrographic basin (Belford Roxo, Duque de Caxias, Itaboraí, Mesquita, Nilópolis, Nova Iguaçu , Rio de Janeiro and São Gonçalo). For five years, the service rate in these cities will remain the same.

The bet in this period is the so-called dry weather collector, with faster implementation. Instead of new pipes connecting houses to the exclusive sewer network, the pollution continues to be drained through the rain drainage network and will be blocked either before the drainage in rivers or in the fluvial channel itself before reaching the bay. From there, it will be directed to the treatment stations, which are currently idle.

It is called dry weather because, in case of heavy rain, the system cannot handle the flow and the polluted water is dumped in rivers. Thus, floods and ditches that contaminate streets and alleys should continue, according to specialists.

“Dry weather does not end the sewage ditch. The objective is to clean up the river in the short term”, he says Adacto Ottoni, professor at the Department of Sanitary and Environmental Engineering at UERJ (University of the State of Rio de Janeiro).

For him, the system is justified as an emergency strategy in the Guandu river basin, main source of water in the metropolitan region. Pollution at the site has generated successive water crises, such as the proliferation of geosmin. “That’s not the case in Guanabara Bay.”

Sanitary engineer Alexandre Pessoa, from Fiocruz, says that the concession should prioritize the improvement in the health of the residents. “Is the system designed to bring an environmental improvement to the bay or to ensure that the population does not come into contact with sewage from the communities?”, he asks.

For engineer Eloisa Elena, the weather dry conditions can benefit those who live on the banks of polluted rivers. However, she claims that the rainy weather, intensified by the climate crisis, could make the strategy ineffective.

“In France, they go six months without a drop of rain. There it is worth it. Our situation is different. Here in our Atlantic Forest biome, it rains every month. Dry weather here is a quick fix.”

All previous plans to clean up the bay were based on the expansion of the “absolute separator” system, in which rainwater and sewage do not mix. Dry weather was first proposed in 2018, by the Metropolitan Chamber, a state government agency.

Urban planner Luiz Firmino, former superintendent of Chamber, defend the model. He claims that investments for dry weather anticipate interventions also necessary for the “absolute separator”, such as the improvement of treatment plants and installation of pumps.

He also says that both models must exist together to guarantee sanitation to the population and clean the rivers.

“There is a failure in the sewer system all over the world. I don’t know of any city in the world that is successful in sanitation that does not have this mix .”

In a research recently completed by the University of Lisbon, the urban planner compared sewage treatment in the Algarve (Portugal) and in the Lagos do Rio region —both mostly use dry weather and have similar populations. The cities of Rio de Janeiro had triple the rainfall of the Portuguese region, but the loss of system efficiency was 14% .

“This does not prevent the use of this system in the tropical climate”, he evaluates. dos Lagos points out a drop in hospitalizations for diarrhea, indicating improvements in the health of residents due to the dry weather. from the private sector to accelerate the environmental improvement of the bay.

“It is a historic demand. Bringing sanitation without depollution to the Guanabara Bay is soon to lose an opportunity to also have the largest environmental project in the It would be to deny for five years something that can happen now,” he said. out of five the years” in the eight municipalities in exchange for dry weather. It also shows that the rates to be charged from concessionaires on sewage remain constant in these cities in the period.

Nevertheless, the government claims that there will be no waiting. According to Riley Rodrigues, special advisor to the Civil House, interventions for the “absolute separator” in this area will begin now, but will only take effect later. During this period, the dry weather works as an emergency measure”, says Rodrigues.

Miccione says that Guanabara Bay is not “jumping the line” of residents, who have been waiting for decades for sanitation basic adequate.

“For other locations, the solutions involve more specific technical issues. It’s not about jumping in line, but the bay has two solution options and not just one,” he said .

Biologist Mário Moscatelli states that, with or without delaying the collection of ideal sewage, the bay needs emergency interventions.

“The patient Guanabara Bay is wasting away day by day. You can’t wait to tackle the causes and then think about the consequences. From an ecological point of view, we are not in a comfortable position.”

The monitor ment of the bay’s waters carried out by Inea (State Environmental Institute) shows the environmental liability. Of the 24 analysis points in 2019 (latest available), had a bad or very bad level average, and 5 were considered regular. None were good or great.

The bathing facilities of the bay’s beaches also show pollution. The one in Botafogo, at the foot of Sugarloaf Mountain, was 99, 8% of the days unsuitable for bathing between 2014 and 2019, according to the Guanabara Bay Hydrographic Basin Committee.

Study of 1994 from Instituto Trata Brasil shows that the lack of basic sanitation is responsible for 14% of hospitalizations caused by gastrointestinal diseases. In the previous year, the total number of hospitalizations was 2.225.

Águas do Rio —winner of blocks 1 and 4 — you have until April 2022 to present an investment plan to be approved by the regulatory agency responsible for overseeing the fulfillment of targets, such as the treatment of 90% of the sewage in the area.

This index does not include slums considered to be undeveloped, which concentrate 1.2 million people in the capital, approximately 14% of the population.

In these areas of the capital, Águas do Rio has the obligation to invest R$1.2 billion in sanitation, regardless of the percentage that this represents for the total number of residents in these areas —the contract does not mention communities in other municipalities.

Um of the prioritized places is the Complexo da Maré, on the shores of the bay. The concessionaire must build a belt around it to collect dry weather.

The neighborhood has a sewer system, but of the five pumps needed, only one is working and in a precarious way.

Like Vigário Geral, the favela complex is close to an ETE, Alegria, but it cannot send its sewage there, and it ends up “in natura” in the bay. The unit works with only 24% capacity.

Ottoni cites Maré as a example of a place where he considers the installation of dry weather to be adequate.

“In areas without urbanization and security, there is no way to implement the absolute separator. It is a risk area for maintenance”, he says the professor at UERJ.

The director of the NGO Redes da Maré, Eliana Sousa Silva, criticizes the argument.

“The State, which does not provide the right to public safety in the favela, uses this failure as an argument to say that it is difficult to provide full access to sanitation. We cannot accept that”, she says.

It was not accepting that residents da Maré created the Cocôzap project, which monitors the region’s sanitation problems. Between May and September, there were 99 records, mostly related to sewage.

“The idea is that participation help to problematize this issue in Maré and to stop naturalizing these problems, which for us are normal. It is to show that we are there and that we matter,” said Vinicius Lopes, project coordinator.

Firmino also states that it is necessary to closely monitor the investments to be made by the concessionaire.

“This design it has to be calibrated. Who will dictate the priority? If you leave it loose, the economy dictates: where it achieves more goals with less effort,” he says.

Alexandre Pessoa, from Fiocruz, is concerned about the State’s ability to oversee the goals. “There are a number of gaps in concession modeling. They are medium and long-term risks.”

Miccione, however, says there will be monitoring. “The depollution of Guanabara Bay is no longer a promise because it is contained in the contract.”


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