The wastewater from Wetzikon is treated in the Flos wastewater treatment plant, which was built in 1961. However, not only the water from Wetzikon, but also from Aathal/Seegräben, Auslikon (Pfäffikon) including the baths, Ober-Balm (Hittnau) and Grüt (Gossau).
It is located at the Flos collection point on Usterstrasse, just by the Aabach.
At that time it was designed for 22,000 population equivalents. Due to population growth, the Flos wastewater treatment plant was expanded at a cost of 43 million Swiss francs. The idea was not only to cope with the growing population but also to keep the plant at the latest technical level, which was achieved with the help of new filter systems. After the conversion, the plant treats 37,000 population equivalents.
The municipal wastewater treatment plant is working at an average capacity of 120 %. For this reason, preparatory work for an expansion of the plant has been underway for some time.
Link
ARA Flos [www.wetzikon.ch]