River swimming in the Seine, Rhine and Danube. How European cities are reclaiming their rivers

For decades, the rivers flowing through Europe’s major cities were known for their unpleasant appearance, foul smell and poor water quality. Today, the situation is changing, and residents enduring increasingly frequent heatwaves have more reasons than ever to cool off with a refreshing swim.

Swimming with a view of the Eiffel Tower

Ahead of the 2024 Summer Olympics, the Paris authorities invested millions of euros in upgrading the city’s wastewater and stormwater systems to allow athletes to compete in the Seine. Pollution levels were significantly reduced, and last year three public bathing areas were opened along the river. Although their operation was complicated by heavy rainfall, they reopened this year.

Parisians and tourists can officially swim near the Hôtel de Ville, the Eiffel Tower and in the eastern part of the capital. Water quality is tested daily, and lifeguards are on duty to ensure the safety of swimmers.

The Rhine and the Rhône, urban bathing in Switzerland

Swimming in the Rhine is one of Basel’s most popular summer attractions. Bathing is permitted only when the water temperature exceeds 18°C and the river level is between 246 and 650 cm. Special waterproof Wickelfisch bags are even sold along the river, allowing swimmers to safely pack their clothes and drift with the current from the Tinguely Museum to the Johanniterbrücke, a distance of 3 km.

In Geneva, meanwhile, visitors can cool off in the Rhône, although local authorities warn that the glacier-fed river can have cold and unpredictable currents. The official bathing area begins just beyond the Sous-Terre Bridge and follows the Sentier des Saules riverside path.

Danube waves for summer cooling

Urban bathing areas have also been established along the Danube, specifically in the Austrian capital. There are five in total, with the most popular located at the Neue Donau, Alte Donau and on Donauinsel, the river island. Vienna’s authorities state that water quality is monitored regularly to ensure safe bathing conditions.

Further downstream in Budapest, water quality was poor and swimming was prohibited as recently as three decades ago. Thanks to major investments in wastewater treatment throughout the Danube basin, conditions have improved, and the city now has two official bathing areas: the traditional Roman Beach in District III and the new bathing area in Árasztó Park in District XI. Before entering the water, however, it is advisable to check whether a temporary swimming ban has been introduced, as local pollution can occur after heavy rainfall or industrial discharges.

The difficult fight for cleaner rivers and cooler cities

River bathing areas are also popular in Copenhagen, Rotterdam and Munich, while activists in Berlin are currently campaigning to legalize swimming in the Spree, where water quality has improved significantly. This year, a bathing area on the River Thames in southwest London opened for the first time.

Urban planners agree that returning rivers to city residents not only creates new recreational opportunities but is also an important part of climate change adaptation. Unfortunately, the task is far from simple. It requires reducing pollution at its source, modernizing wastewater and stormwater infrastructure, restoring natural riverside ecosystems and developing reliable water quality monitoring systems.

As Eline Boelee, a water and health expert at the Dutch research institute Deltares, explains, the main problem is outdated infrastructure. These systems were designed to handle average capacity. During heavy rainfall, they become overwhelmed, causing untreated water to overflow into surface waters.

Heavy rainfall carries pathogens, antimicrobial-resistant bacteria and chemical pollutants such as PFAS into rivers. These are the challenges that urban river bathing areas must contend with throughout the summer.