In a city with 100,000 inhabitants, for example, 10,000 to 12,500 m³ of wastewater containing faeces is produced every day. This wastewater is channelled through the sewage system to the treatment plants, where it is purified and discharged back into a river. The wastewater passes through various purification stages, from the removal of coarse foreign matter, to the settling and pumping of mineral components in the grit chamber, to biological purification using microorganisms, oxygen and sufficient time. The purified wastewater leaves the treatment plant after 24 to 36 hours.
It is hard to imagine the consequences of the sewage treatment plant coming to a standstill. In the past, a treatment plant foreman even lived on site to monitor the plant. Today, on-call services take over this task. However, the best solution is an early warning of impending complications.