Last week, we wrapped up De Oorzaak with nothing less than a bang. With in-depth stories featured in De Morgen, striking results on the table, and a “tour across Flanders” that brought us to Antwerp, Ghent, and Leuven, the project ended on a high note. The closing events weren’t just symposia – they were the grand finale of a citizen science project that has kept us occupied for the better part of two years. Each evening was a meeting point between science, citizens, and policymakers, weaving data and lived experience into one story about noise in our cities.

Noise is more than just an irritation – it shapes how we live, sleep, and feel.
The results from De Oorzaak make this crystal clear: almost half of all measurement points were, on average, above 60 dB during the day – a level already higher than the World Health Organization recommends. Unsurprisingly, traffic was the worst culprit across the board. But we also saw how local noise sources – like tourist boats or tram rails – can have gigantic impacts on daily life in specific neighborhoods.

And those numbers are only part of the story. Behind them are the voices and experiences of people who live with noise every day. At the symposium, participants shared endless varieties of stories – some tragic, some creative, all deeply personal. They showed just how differently noise can affect lives, and how much effort it takes to raise awareness.

The consequences are clear, as shown by our data: the more noise we are exposed to, the more annoyed we become. Annoyance spills into reduced sleep quality, and ultimately into a diminished quality of life.

Browse the beautiful visual stories from media partner De Morgen here: https://www.demorgen.be/redactie/2025/oorzaak-resultaten/index.html

🗺️ If you don’t have a subscription to De Morgen, you can explore this beautiful interactive map of Lden values and noise events at each measurement point, including AI-detected sources binned by the peak noise level per event, as made by our data wizard Ablenya Barros: https://ablenya.github.io/Oorzaak/Sensors_noise_events.html.

Yet there is also hope – and it’s green. Across the data, one message stood out: nature helps. Green spaces and natural sounds soften the harsh edges of our urban soundscapes. Even when the decibel levels are not lower, the presence of rustling leaves, birdsong, or flowing water transforms how we experience sound. Nature doesn’t necessarily quiet our environment – it restores us.

The next question is: what will we do with this knowledge? At each evening of the symposium, policymakers were confronted with that exact challenge. The most striking message came from the city counsillor of environment in Leuven, who put it simply: this is the new normal: citizens now have the data to show there is a problem – giving them a lot more power again. But solutions will not be easy, and they never have been.

So where do we go from here? The evidence is clear, the stories are real, and the momentum is growing. If we want healthier cities and better lives, the answer is again clear: we need more green in our cities.

There is much much more depth and nuance to this story than I can tell here and now, but we hope we can get back to you about all that! For now, check out this first post here: https://www.uantwerpen.be/nl/projecten/de-oorzaak/nieuws/.