Heat wave meets Hamburg: BUND demands green sponge city implementation!

Heat wave meets Hamburg: BUND demands green sponge city implementation!

The heat wave has a firm grip on Hamburg and the temperatures rise over the 30-degree mark. In this brooding heat, the call for a climate -adapted "sponge city" is loud to relieve the city climate. The BUND Hamburg now vigorously demands the implementation of this concept, which provides less concrete and more nature in the city. Sabine Sommer, chair of the BUND Hamburg, urgently warns that the climate crisis can no longer be ignored. She emphasizes that extreme weather conditions such as persistent heat waves and drought events have increased and demands a rethink in urban planning.

As the reports of the BUND Hamburg show, March 2025 was one of the driest months since 1881, with just one fifth of the normally expected rainfall. In addition, 89 waters in Hamburg are either completely dry in 2018 and 2019 or only led minimal water. These alarming developments show the urgency of an adaptation of urban infrastructure to the changed climatic conditions.

sponge city as a solution

The sponge city concept has the goal of storing rainwater through nature-related urban development and using it sensibly. In order to get the climate changes under control, numerous measures are required: more street trees, green roofs and deflected places are just a few suggestions. The goal is clear: a better green and blue infrastructure to withstand the drastic heat and heavy downpours.

The advantages of trees are undisputed. They lower the temperature by up to 3 degrees, evaporate up to 400 liters of water every day and contribute to CO₂ storage and oxygen production. The BUND actively supports projects for refrigeration and greening as part of the network "paving", and it is time that the citizens also make their contribution. Everyone can contribute to improving the urban climate with small changes such as unsealed entrances or front gardens.

important projects and potential dangers

The discussion about the sponge city comes at a critical time. Current major projects such as the A26 East or the development in Oberbillwerder and Wilden Wald threaten valuable natural areas. Here is a great risk for the city's already stressed environment. The warnings are clear: does it really have to come that far, or can a rethink save the endangered areas?

The Federal Government has already dealt with the German adaptation strategy to climate change (das) in order to create a political framework for adaptation. This concept for urban water management is crucial to promote active change in urban development, which meets the requirements of climate change. Many cities are already working on green infrastructure, and there are various strategies for adequate rainwater management in urban areas.

summarized it is shown that Hamburg is willing to make changes to meet the challenges of the climate crisis. It is up to the city and its citizens to recognize and implement the potential of the sponge city. It is to be hoped that these ideas will not only be on paper, but will soon become a reality.

For more information about the sponge city concept and the ongoing initiatives in the city, interested parties can read here: Environmental Federal Office .