A quiet but growing problem is building up in the Seine Amont wastewater treatment station in Valenton, Île-de-France, as people return to their usual routines after the start of the school year. The station processes wastewater from over 2.2 million people every day, with a flow rate that can reach 15 cubic meters per second. The issue is caused by wipes, even those labeled as "biodegradable," which contain plastic fibers that do not break down and accumulate in the station's filtration systems. Olivier Browne, the site director, says the screens capturing solid waste are about 80% full of wipes, a number that includes all types of solid material retained, regardless of their original purpose. The Seine Amont station, which began operating in 1987, is the second largest wastewater treatment plant in Île-de-France, capable of handling the waste of 3.6 million people. It can process up to 1.5 million cubic meters of water daily during heavy rain. Designed to manage water, organic matter, and a certain amount of typical solid waste, the station was not built to handle the large volume of synthetic textile fibers coming from wipes. Originally intended for secondary filtration, the screens are now the first line of defense, trapping wipes before they clog pumps and interfere with the downstream treatment process. The buildup of wipes has led to more frequent manual and mechanical removal, increased maintenance of equipment that is wearing out faster, and ongoing monitoring of pumps at risk of becoming blocked. These efforts require time, equipment, and energy, but the associated costs are not passed on to residents through their water bills. Even though the station has undergone modernization, including the installation of a thermal drying unit and a biogas production unit, more and more resources are being used to tackle this preventable waste problem. Local authorities are running more awareness campaigns, reinforcing the message that "no toilets for wipes." Some manufacturers have started producing cotton wipes that are genuinely biodegradable, but these remain a small part of the market. According to experts in the water sector, most products sold still contain synthetic fibers that do not decompose in the sewer system. The simplest and most effective action is to throw used wipes in the trash instead of the toilet. This small change in personal habits could greatly ease the pressure on infrastructure that is already operating at full capacity.