The heavy rain catastrophe in the west and south of Germany demonstrates it in a drastic way: The weather is becoming more extreme – here too. German scientists have now summarized in a statement which lessons should be drawn from this for the future and how municipalities can arm themselves against future events of this kind. Above all, they list five central principles with which municipalities and cities can be made more climate-proof.
In July 2021, heavy and long-lasting rainfall in North Rhine-Westphalia, Rhineland-Palatinate, Bavaria and Saxony caused severe damage to infrastructure and buildings. Roads and rails were washed away, houses torn away by the water of the swollen rivers and cellars flooded. There were injuries, missing persons and deaths to an extent that was previously unimaginable for Germany. In contrast, the periods of heat and drought in 2018 and 2019 manifested themselves completely differently, but also with serious consequences.
More climate security for municipalities and cities
Climate studies show that such weather extremes are only two sides of the same coin, despite all the differences: Both types of events – heavy rain as well as heat and drought – are increasing in the course of climate change. In the future, we will therefore have to reckon with these extremes more frequently in Germany as well. It is all the more important to learn the right lessons from recent events. Researchers coordinated by the Helmholtz Center for Environmental Research (UFZ) have now summarized what these could be. You have defined five essential principles that cities and municipalities should use as a basis for their conversion for more climate security.
“Climate change poses enormous tasks, especially for municipalities and cities. It is therefore important to jointly advance the renovation of cities and municipalities, buildings and infrastructures as well as ecosystems and prepare for new weather dynamics, ”explain Christian Kuhlicke from the UFZ and his colleagues. “It is important to further strengthen risk management of extreme weather and civil protection as well as strategic planning in municipalities and cities. The aim must be to put the climate security of communities and cities on a new footing. This requires the further improvement of our knowledge base, but also the cooperation of all actors, including politics and the authorities of the federal and state governments, private companies, associations and the individual people on site. “
Warning systems, retention areas and reconstruction
The scientists propose the following measures: First, the early warning systems should be improved and civil protection should be strengthened. In concrete terms, this means improving the forecast of floods for smaller river catchment areas and establishing reliable warning systems. In addition, communication with local authorities and citizens must be improved. Experience with the most recent heavy rain has shown that weather warnings and their possible consequences are often not understood. “Only a warning that people understand and trust will lead to the desired actions,” emphasize the researchers.
Another measure is to protect communities, cities and landscapes not only with established protection solutions such as dykes, walls and polders, but also to increase the so-called sponge ability. Alluvial meadows, forest areas and urban green spaces increase the water retention capacity of the subsoil and thus delay the runoff of rainwater into the rivers. When rebuilding the destroyed buildings and towns, greater consideration should be given to climate security than before, both for new buildings and for renovations. Protection standards must be increased, particularly in facilities that accommodate particularly sensitive groups such as children, the elderly or disabled people.
“Similar to energy-efficient refurbishment, this requires financial support and incentive instruments as well as the establishment of preventive insurance premiums,” explain the scientists. “Trying to master future challenges in existing buildings in an appellative or reactive manner will not be enough.”
Better secure infrastructures
Public funds will also be needed to better protect critical infrastructures against damage and failures. “It is unacceptable when necessary communication networks, medical services and facilities fail during a crisis because they are not adequately prepared for such extreme events,” state Kuhlicke and his colleagues. “Infrastructures (supply of water, electricity, etc.), the backbone of our modern society, must be designed in such a way that they also function in extreme weather conditions or allow appropriate fallback options.”
As the scientists emphasize, none of these proposals and the associated measures are new: “Many of the demands were made public after the major floods in 1993 and 1995 on the Rhine and in the aftermath of the destructive floods in 2002 and 2013. This statement is intended to underline its importance again, ”said the team. It is clear, however, that the restructuring requires a will to innovate and shape on the part of cities, municipalities, investors and private individuals, as well as the use of financing and incentive instruments by the federal government and the states.
In addition, the scientists emphasize that even measures that can only be implemented in the long term, such as the conversion of infrastructure systems, must not be delayed – the foundations for this must now be laid. “It is now time to act,” said Kuhlicke and his colleagues in their statement.
Source: Helmholtz Center for Environmental Research; Five principles