On Friday, May 22, a local resident told a wildlife ranger that the river Le Diron, in Vuadens (FR), had a strange appearance: grayish, turbid, cement-like water. A technician from the environmental service came by and confirmed that someone had poured cement-laden water into the waterway. The pollutant reached the confluence with the Sionge River, where it dissolved.
What is striking is how the authorities reacted. To determine where exactly the contamination was coming from, they used a yellow, non-toxic fluorescent dye injected at the likely entry point. The goal is for it to appear somewhere upstream and allow the source to be identified. The dye may remain visible in the river for the next few days.
So far, no dead fish have been found. The ecosystem has been affected, but apparently without serious consequences. The investigations continue. Who did it and why, at the moment it is not known. Someone may have carelessly cleaned a cement mixer. It may be something more deliberate. The cantonal police of Fribourg do not give more details.
What this little incident does say is something about Switzerland: that a spill into a modest small-town creek triggers a technical response, with measurement, tracing dye, and official communication. In many other places, this kind of thing would happen without anyone knowing.