Clean water for Mexico City

The largest sewage treatment plant in the world for Mexico City is currently being built in the Mexican city of Atotonilco.

For more than half of the sewage volume

The sewage treatment plant is located north-east of the Mexican capital. In future, the new plant will treat around 60 percent of the sewage of 20 million inhabitants of the state capital. The area of the plant is several square kilometres.

Redundant design

The sewage treatment plant is consistently designed for safety and consists of two redundantly configured clarifying strands that run in parallel during normal operation. The same redundancy is found in the PLC hardware for the mechanical pre-treatment, so the system can continue to operate even if technical problems arise. SPANGLER planned and configured the 16 control cabinet fields that are needed for this using EPLAN Electric P8. The plant is divided into three area substations, each of which SPANGLER has clearly displayed in on a touch panel.


An integrated motor management connects the higher-level automation system and the motor feeder. In this way, the operator always has an overview of the current operating status of the drives. The corrosion-resistant construction protects the controller hardware against aggressive substances.