The unexpendables at the end of the line

Luc Ley opens the first door to the plant, which "doesn't exist in most people's minds, but always has to work". He is responsible for the sewage treatment plant in Beggen, a huge complex by Luxembourg standards, but passers-by generally notice little of it. Contrary to all kinds of prejudices, visitors and workers smell nothing even inside the plant, except in some rooms. The air is filtered so often before it leaves the building that even the chimney on the roof is odourless. "Not what you expected, is it?" enthuses Ley, who would like to have visitors more often to bring the work that is done here a little more into the public eye. Because it is often only noticed when something goes wrong, although a little more attentiveness would make it much easier.

Here, on the border between Luxembourg City and Walferdingen, the wastewater from the municipalities of Luxembourg, Bertrange, Strassen, Leudelange-Schléiwenhaff, Roedgen and part of Findel flows together to find its way back into the Alzette after a complex treatment process. The largest sewage treatment plant in the country can currently serve around 210,000 inhabitants, explains Patrick Licker, who is responsible for the sewerage service of the city of Luxembourg. In addition to the 124,000 inhabitants of Luxembourg City, there are also commuters – who produce the equivalent of half a person – as well as wastewater from shops, restaurants and industry. All these factors will soon push the existing wastewater treatment plant to its limits. An upgrade is necessary. According to Licker, the new plant, which is scheduled for completion in 2030, will be able to serve 450,000 population equivalents.