In an exclusive interview for the G20 Brasil website, hydrologist and architect Elenisa Ávila Campos emphasizes the importance of integrated public policies for urban management and tackling extreme weather events. The expert advocates the implementation of models such as "Sponge Cities" for sustainable environmental protection.
The climate crisis is addressed in different forums in the G20 discussions: the Global Climate Change Mobilization Task Force, the Working Groups on Environment and Climate Sustainability, Agriculture, Disaster Risk Reduction, Energy Transitions, Sustainable Finance, and the Bioeconomy Initiative.
One of the highlights of the discussions so far was the accord signed between Brasil and the United States to strengthen environmental ties, focusing on clean energy, the carbon market, and sustainable finance. The accord was signed during the G20 by the Minister of Finance of Brasil, Fernando Haddad, and the US Secretary of the Treasury, Janet Yellen, and aims to accelerate the energy transition and raise funds, highlighting the importance of global climate cooperation.
The deliberations carried out by the G20 have the potential to influence not only the member countries but also to establish global guidelines on how to deal with the consequences of climate change and the increase in natural disasters. The discussion becomes even more relevant with G20 meetings focused on environmental issues.
In an exclusive conversation with the G20 website, hydrologist and architect Elenisa Avila Campos, PhD in geography and specialist in regional urban planning, analyzes the complexity of urban drainage and the importance of innovative approaches such as the sponge cities. The theme has a global perspective, especially in light of recent extreme weather events that have impacted cities around the world.
Elenisa, who is also a professor at the Federal University of Rio Grande do Sul (UFRGS) and a researcher at the Observatory of the Metropolis in the city of Porto Alegre, believes that this discussion on urban drainage is vital for several disciplines from engineering to architecture, but has never received the necessary attention, according to the hydrologist. She points out that drainage, or the management of rainwater flows, has been neglected amid rampant urbanization and the uncontrolled action of real estate markets. "The lack of regional and metropolitan policies in Brasil aggravates the problem even more, making water management a fragmented and ineffective task," she says.
The expert cites the case of Porto Alegre, in southern Brasil, which has experienced a historic flood. In her opinion, it was no use for local management to take isolated measures without recognizing the regional dynamics. She defends integrated policies, and in the case of Rio Grande do Sul, she criticized the lack of planning and the absence of a systemic approach, which considers both urban density and soil impermeability. "What we have seen are the effects of political decisions and economic interests that neglect the environmental balance," says Elenisa. She cites the amendment to the Environmental Code of Rio Grande do Sul as an example of how easing laws can have devastating consequences.
What are Sponge Cities
In a global context, where climate change intensifies extreme events, the hydrologist emphasizes the need for public policies that prioritize sustainability. She advocates that Brazilian cities adopt the "sponge cities" model, originally developed in China and implemented in some regions of Europe, as a possible solution to tackle the new climate reality of more frequent extreme events in places of high urban density and in need of efficient water management.
The expert explains that sponge cities are urban areas designed to absorb, retain, and reuse rainwater, reducing flooding and improving water resource management. The process replicates the natural water cycle using green infrastructure, such as parks, gardens, and permeable pavements. This strategy aims to prepare cities more sustainably for dealing with the consequences of climate change. "The whole world is preparing for the processes that will be happening from now on," she stated, stressing the importance of learning from these initiatives.
Within the scope of the G20, the hydrologist hopes that the discussions will move forward and translate into concrete actions. "It is necessary that global policies are reflected in local actions, adapted to the specificities of each region," she argues.
Elenisa says that one of the most important strategies for reducing the effects of flooding is protecting riverbanks, which are considered Permanent Preservation Areas (APP) under the Brazilian Forest Code. "The definition of the minimum areas to be protected aims to ensure that the general functions of these areas are minimally safeguarded, both in rural and urban areas," she observes.
Sponge cities are urban areas designed to absorb, retain, and reuse rainwater, reducing flooding and improving water resource management. The process replicates the natural water cycle using green infrastructure, such as parks, gardens, and permeable pavements. This strategy aims to prepare cities more sustainably for dealing with the consequences of climate change. "The whole world is preparing for the processes that will be happening from now on," she stated, stressing the importance of learning from these initiatives.
The hydrologist emphasizes the urgency of restoring the government's role in managing environmental resources and protecting vulnerable populations. "Governments have a responsibility to ensure that urban spaces are safe and sustainable for everyone," she warned. She calls for urgently revising master plans to include robust environmental principles.
The statement by Elenisa Ávila Campos is a call to action as the world faces the challenges of climate change. The researcher argues that collaboration and innovation are essential for building resilient and sustainable cities. She concludes that the G20, as a forum of world leaders, "has the opportunity and the responsibility to guide these transformations towards a more safe and sustainable future."
