Marilotte Stemerdink
TU Delft
In the summer of 2025, the mayor of Paris, Anne Hidalgo, opened three brand-new swimming sites in the River Seine. The inauguration came a year after images of her dive into the river—ahead of the Olympic Games—went viral worldwide. Thanks in part to developments in Paris, urban bathing is now playing an increasingly prominent role in debates about the quality of urban water and the liveability of cities. This global swimmable cities movement is also fuelling Rotterdam’s growing ambition to tackle heat stress and improve access to its waterfronts through urban bathing. The pilot swimming site at the “Floating Park” in the Rijnhaven has shown just how great the enthusiasm is: it has quickly become immensely popular with both Rotterdammers and visitors.
This graduation research, conducted in collaboration with the Municipality of Rotterdam and Swimmable Cities, explores various ways to build on this success. The study ties in with ambitions set out in the Water Atlas Binnenstedelijke Nieuwe Maas, in which the city designates certain harbours as “hospitable harbours”—places where water contact and recreation take centre stage as traditional port activities shift further away from the urban core. The research looks at three hypothetical locations for urban swimming within Rotterdam’s harbour areas, exploring the challenges and opportunities for implementing swimming facilities.
Three Typologies of Urban Bathing
Around the world, urban bathing takes many forms. Notable examples include the Harbour Baths in Copenhagen, the Badeschiffs in Berlin and Vienna, and the Marineterrein in Amsterdam—which, as of this year, is the first officially designated swimming site in the city centre. With these international cases in mind, the study identifies three main types of urban bathing:
- The Free Style: Swimming directly in open water, with minimal infrastructure. Rotterdam’s Rijnhaven swimming site is an example of this model.
- The Protected Plunge: A demarcated “pool” within the harbour, offering added safety.
- The Dip in a Bowl: A floating pool with purified water, independent of the harbour’s water quality.
Three Rotterdam Harbours Under the Microscope
Spoorweghaven
Spoorweghaven currently offers considerable space but is officially designated as a marina. The study highlights the main challenge here: the tension between its current designation and the desired recreational use. On the other hand, the opportunities for The Free Style are significant: the scale and relative quietness of the harbour lend themselves well to swimming without extensive facilities or side activities, year-round.
Urban bathing in the Spoorweghaven could breathe life into an underused harbour, meet local demand for public amenities, and strengthen the connection between the waterfront and the surrounding neighbourhoods. It could also revive historical associations with past harbour uses while bridging towards future developments of the surrounding urban area of Rotterdam South. Moreover, swimming here aligns with Rotterdam’s culture of urban experiments and sustainable innovations, as seen in local initiatives such as the Rotterdam Makers District and BlueCity. The Marineterrein in Amsterdam provides a successful precedent for this approach.
Coolhaven
Coolhaven is already a popular, though informal, swimming spot. In summer, young people jump into the water from the quay at Tuschinskipark, despite the city-wide swimming ban. Assuming this existing dynamic should not be suppressed but supported, the main challenge lies in the limited space and the need to ensure safety within a bend of a shipping route.
A seasonal facility in the form of a Protected Plunge—comparable to the new swimming sites in the Seine—could best suit this logistical situation while complementing the lively, informal character of the area. Establishing a designated swimming zone in Coolhaven would help all stakeholders work towards a common goal of better regulating the current practice. Positioned on the Delfshaven side of the quay, the facility would also align with local ambitions to improve quality of life and connectivity in the area (the “rondje Coolhaven”), while creating room for more social activities.
Persoonshaven
Persoonshaven is on the brink of one of Rotterdam’s largest urban redevelopment projects in the coming years. This raises the urgency for inclusive public amenities, especially given the expected growth in housing and the arrival of new resident groups.
Here, the opportunities are clear: a Dip in a Bowl—a floating pool with purified water—could serve as a reliable and multifunctional neighbourhood landmark, playing a key role in placemaking. According to the study, such a facility could not only activate the neighbourhood and encourage local ownership, but also contribute to broader urban goals such as inclusive public space, swimming proficiency, and social cohesion. A relocatable floating pool could later be introduced in other developing areas as well, such as Merwe-Vierhavens (M4H).
Swimming as a Driver of Urban Development
The study’s key recommendations emphasise the importance of integrating urban swimming into existing urban ambitions and planned redevelopment projects. The Rotterdam case studies show that swimming in harbours should not be seen as a stand-alone facility, but as part of wider spatial and social development strategies for the city.
In Rijnhaven, the floating park paved the way for a swimming site; in Spoorweghaven, Coolhaven, and Persoonshaven, swimming could instead act as a catalyst for improving the quality of new waterfront living environments. Linking these facilities to the Water Atlas is crucial: swimming sites contribute to the vision of the Nieuwe Maas as Rotterdam’s central urban park. They make the water more visible and accessible, while supporting current ambitions in climate adaptation, health, and liveability.
Beyond providing cooling in summer, swimmable harbours primarily create new places for meeting, activity, and vitality. As such, Rotterdam gains a powerful tool for shaping its urban future: a new, more sustainable economic model for the use of water.
The full research report can be accessed via the TU Delft Repository: https://resolver.tudelft.nl/uuid:1f48d37f-29f4-4274-8d32-81f6c39a0b71
The article was originally published in Dutch on De fijne stad.
Acknowledgements
This blog post has been written in the context of discussions in the LDE PortCityFutures research community. It reflects the evolving thoughts of the authors and expresses the discussions between researchers on the socio-economic, spatial and cultural questions surrounding port city relationships. This blog was edited by the PortCityFutures editorial team: Yi Kwan Chan.