Water scarcity, flooding, and overburdened infrastructure pose enormous challenges for megacities around the world. This is particularly evident in Mexico City, a metropolis with a population of 23 million. Christopher Funk, a student in the master’s program “Sustainable Water Management and Engineering” at Hof University of Applied Sciences, investigated how innovative concepts can contribute to sustainable water management during a research semester in the winter semester 2024/25. On behalf of the Institute for Sustainable Water Systems (inwa), he analyzed the potential of the so-called sponge city concept at two schools in the Mexican metropolis.
The sponge city concept is a central component of research and teaching at inwa. Christopher Funk had already dealt with related issues as a student assistant when he expressed his desire to spend a research semester abroad. Mexico City was an obvious choice as a research location, as the city suffers from massive water shortages despite high rainfall. Large water losses in the pipe network, falling groundwater levels, and the consequences of climate change further exacerbate the situation.
Prof. Günter Müller-Czygan from inwa recalls:
Mr. Funk approached me about the research semester in Mexico City when we were working on digitizing a green roof at a primary school in Schauenstein. This raised the question of how schools in Mexico City are dealing with the challenges of climate change and what role sponge city solutions play in this.
Prof. Günter Müller-Czygan
The sponge city concept: storing water instead of draining it
The sponge city concept was developed in the mid-2000s and has been systematically implemented in China since 2013 to make cities more resilient to heavy rainfall and flooding. The basic idea is simple: rainwater should not be drained away as quickly as possible, but stored where it falls. Green roofs, infiltration areas, or planted hollows allow water to be retained in the soil, filtered, and returned to the groundwater. At the same time, these measures promote evaporation during dry periods and thus cooling—an important contribution to combating urban heat islands. In Mexico City, too, there are initial initiatives that focus on green-blue infrastructure and the importance of soil. The key here is the interaction between overarching urban strategies and many smaller individual measures. Schools play a special role in this context, as they not only provide space, but are also places of learning and awareness-raising.
Schools as key locations for water awareness
In his research project, Christopher Funk focused on two selected schools in Mexico City. The aim was to investigate which sponge city elements could be usefully implemented there, which conditions would promote or hinder their implementation, and what recommendations could be derived from this. This approach was inspired by earlier studies conducted by Hof University of Applied Sciences, which had shown that real-life sponge city solutions can also offer great added value in primary school education.
“It was impressive to see how much the sponge city concept can enrich everyday school life. Even simple, pragmatic solutions had a noticeable effect in dealing with water scarcity.”
Christopher Funk
Scientific approach with practical relevance
Methodologically, the study relied on a mixed-methods approach that combines qualitative and quantitative methods. Based on a systematic literature review, social, economic, and political evaluation criteria were developed, which were then supplemented by interviews with school administrators and teachers. The statements of the respondents were evaluated, compared, and combined in a decision-making model to assess the overall potential of sponge city approaches in schools.
Results: High social potential, structural hurdles
A primary school in the Iztapalapa district and a secondary school in the Gustavo A. Madero district were examined. In both cases, high social potential was evident: sponge city measures can be easily integrated into everyday school life and are widely accepted by teachers and students. At the same time, significant limitations became apparent. Economic uncertainties, particularly with regard to financing and maintenance, as well as unclear building regulations and a lack of political support limit the possibilities for implementation.
While the secondary school fared somewhat better due to more favorable financial conditions, the political environment remained a key inhibiting factor at both locations.
Recommendations for action and outlook
Christopher Funk derived specific recommendations from the results. These include better access to green spaces, greater integration of sustainability into teaching, the promotion of external partnerships, clearer legal frameworks, and more intensive cooperation with authorities. Long-term financing and further research with a larger sample size were also identified as important next steps.
Contribution to sustainable urban development
The research project thus demonstrated how university research can provide concrete answers to global challenges. The example of schools made it clear that sponge city concepts are not only technical solutions, but also have social and educational impacts. For megacities such as Mexico City, this can be an important building block on the path to greater water security and sustainable development – with impulses from Hof that reach far beyond the region.
