‘Entire cities in RS will have to change location’, says researcher who warned of unpreparedness against rain | Environment

“O rain behavior has changed. I have been doing a survey and I have already noticed that from 2013 onwards we have accumulated precipitation [chuvas] in the month of more than 300 ml. My question is: What have we, for example, in Civil Defense, programmed to foresee these possibilities? At some point we will start to see [inundações] in areas where water didn’t reach as often and let’s remember that’s what we’re talking about here.”

The warning above, made in June 2022 during a public hearing at the Municipal Council of Pelotas (RS) and highlighted in videos on social media as “prophecy” in light of the floods that have already left at least 90 people dead in Rio Grande do Sul, it is ecologist Marcelo Dutra da SilvaPhD in science and professor of Ecology at the Federal University of Rio Grande (FURG).

⛈️ On the occasion, during a debate on climate changesthe researcher drew attention to the fact that many cities in Rio Grande do Sul were totally unprepared for extreme rainfall: they did not know which areas were at risk, which regions were vulnerable to flooding, or who would be the first residents of the state to be hit by the waters.

“We can’t prevent the climate event from happening, nor the next ones, because they will happen. But can we be more resilient to it? Yes. Maybe if we had already moved people away from the highest risk areas. Is it possible to know where the event will occur? becomes more serious first”, he ponders, adding that environmental planning would have made it possible, for example, to remove residents from the most vulnerable areas in advance.

Faced with the devastating floods that hit Rio Grande do Sul less than six months after floods that destroyed part of the Rio Grande do Sul mountain range in November last year, the researcher argues that, this time, the Public authorities’ response needs to change radically.

“There’s no point in trying to rebuild everything that was destroyed in this event trying to make it the way it was before. That’s no longer possible.”

The reconstruction of Rio Grande do Sul, says the academic, will need to be planned considering which areas are the safest and most resistant to extreme climate variationswhich are here to stay.

“Entire cities will have to change location. It is necessary to move urban infrastructures away from these highest risk environments, which are the lowest, flat and humid areas, hillside areas, riverbanks and cities that are within valleys “, it says.

Such changes will involve what he calls “deedify“: remove structures from cities that are in risk areas and start over in safer regions.

“We need to return these spaces that are most sensitive to flooding to nature,” he says.

Much of the unpreparedness of cities for the new climate reality occurs because they grow without considering the geography of the State and its levels of vulnerability in the face of climate forecasts, as well as the preservation of nature.

“Municipalities in Rio Grande do Sul have been facing strong urban growth over remaining humid areas”, he explains.

It’s not just about removing the population who live in hillside areas, but all regions are sensitive to flooding and landslides.

In general, the areas most valued by the real estate sector for large projects and by the population themselves are precisely those most vulnerable to flooding: close to the banks of rivers and lakes, or in flat, low-lying and humid areas.

In addition to being less resilient, wetlands play an important role in preventing floods, as they should serve as “sponge” in periods of heavy rain, explains the researcher.

“These areas are important because they have what we call the sponge effect: this service provided by nature is precisely so that when there is a large load of water it goes there, and the higher areas remain safe”, he says.

From the point of view of environmental risk, urban expansion decisions have gone against safety, says the ecologist.

“We are doing the opposite of what we should: we are going where we shouldn’t go, exposing ourselves to risk, creating situations that put lives in danger, and recurring losses.”

Another geographical aspect of Rio Grande do Sul that needs to be considered when adapting to the new climate reality is that there are many cities located within river valleys, which are low-altitude areas surrounded by higher areas, such as hills and mountains, and close to the water.

“There are several entire cities that are in the valley region: areas subject to receiving large loads of water in an extreme event like this. And then there is no point in rebuilding that city within the valley, because it will continue to be threatened. Because climate events will continue repeat”, he says.

He cites the example of Muçum, a city in the Taquari River Valley.

A report by BBC News Brasil showed that the municipality had already been affected by floods three times during 2023 – the first in June, which killed 16 people in the state; in September, when 53 people died as a result of the passage of an extratropical cyclone; and in November, when more than 700,000 people were affected by torrential rain.

“We have examples of cities that were hit in 22, 23, and people lost things for the fourth time, like Muçum, Lajeado. Some people are already so discouraged that they say in interviews that they didn’t even buy more furniture, more cars, because they know that they will lose again”, he says, highlighting that in this case, the government’s failure was to allow families to rebuild their lives in the same place, without offering safer housing plans.

“This new reconstruction plan needs to come with a climate change adaptation plan,” he states.

The academic, who advocates that all affected cities review their master plans before rebuilding everything that was lost, says that “there is no point in wanting to build, or rebuild everything that was destroyed in this event now trying to make it like it was before”.

For the professor, both the state and federal governments could encourage such reviews, perhaps placing them as requirements for city halls to have access to resources to finance reconstruction.

The governor of Rio Grande do Sul, Eduardo Leite (PSDB), has already declared that the State will need a “Marshall plan”, making reference to the reconstruction plan in Europe after the Second World War.

The city reconstruction plan, warns the researcher, can no longer be based on buildings in low, flat and humid areas and environments on the banks of rivers, lakes and streams, as happens in many cities on the coast, such as Pelotas, and even in neighborhoods of Porto Alegre close to Lake Guaíba.

“The look from now on needs to be more technical, and think about adapting the city to such extreme situations.”

“Critics will say that we are only concerned with biodiversity, and argue that we need to think about people’s lives, about development. If I were only concerned about biodiversity that would be fine, but we are not even talking about that anymore, in this case”, he states. “We’re talking about survival, because it means you put a business there and it stays underwater.”

Another important aspect of the State’s reconstruction, which will be long and arduous, will be investing in structures that are better prepared for climate events.

“We will have to rebuild, yes, but now thinking about bridges that are much higher and more robust, roads that are much more prepared and resilient to such extreme processes of water presence.”

Technologies to alert the population more efficiently about potential disasters, in the professor’s view, have limited effect if they are not accompanied by more drastic changes.

“Any warning technologies will be useless if we continue to keep people and infrastructure in places that will always be at risk. What’s the point of warning people to leave if they are going to lose absolutely everything?”, he asks.

“The quick investment will have to be in correcting these cities, in updating these cities, so that we become more adapted to this new condition. Because it’s not just warning.”

On another front, the researcher says that it is necessary to invest in less centralized ways of building cities, in order to allow water to flow more easily into the ocean.

“We need to allow water to pass, for water to flow, instead of trying to block it. We have to recover, for example, natural vegetation in permanent preservation and production areas.”

Another recommendation, considering that extreme weather events also predict periods of intense drought, is to take advantage of rainy periods to store water in dam systems or other water reservoirs.

“A lot of this water raining now is simply being lost and at some point it will be missed, because it is raining a lot now and it will rain very little later.”

Convincing the population that the new climate reality is here to stay, he says, is an important part of the work to prevent new environmental tragedies.

“Unfortunately, there are people who think this happened, but tomorrow is over and life goes on”, he laments. “It’s not a moment; it’s a period that maybe will be like this for a long time, and we need to prepare ourselves to fit into it.”

VIDEO: Animals are rescued after floods in Canoas (RS)

Animals are rescued after floods in Canoas (RS)