Hydraulic Engineering Team completes the expansion of the Bad Zurzach wastewater treatment plant

The expansion of the Bad Zurzach wastewater treatment plant was carried out by the hydraulic engineering specialists at ERNE AG Bauunternehmung in close collaboration with Gebrüder Meier AG Rohrleitungsbau.

The expansion of the Bad Zurzach wastewater treatment plant (ARA) is being carried out by the hydraulic engineering specialists at ERNE AG Bauunternehmung in collaboration with Gebr. Meier AG Rohrleitungsbau. Due to stricter discharge regulations imposed by the Canton of Aargau, an expansion of the existing plant was necessary to comply with these requirements. The project is being carried out in three stages and involves the construction of new primary and secondary clarification tanks as well as the conversion of existing tanks.

In the first stage, which began in February 2019, six new concrete tanks and technical rooms were constructed. F-concrete, which is particularly resistant to aggressive influences such as sewage, was used for the tanks. In addition, all components were tested for watertightness, which required precise planning of the construction process. In the second phase, starting in June 2020, the partial demolition of an existing combined tank took place. A detailed demolition plan was necessary, as only a load of 18 tonnes was permitted around the tank. The demolished material was reused, and the new funnels were filled with SCC concrete.

The existing tanks had to be adapted to the increased capacity. To this end, the parapet was raised by one metre, whilst the walls were cleaned with high-pressure water jets, anti-corrosion protection was applied and watertightness was ensured. In addition, a special formwork system for circular columns was used inside the tank. The first aeration tank came into operation at the end of 2020.

Gebrüder Meier AG Rohrleitungsbau laid various PE pipes between October and December 2020 for overflow and pump lines, as well as for the municipality’s drinking water supply. Industrial hydrants were also replaced and reconnected. The third phase, comprising the demolition and conversion of the second combined tank, began in May 2021 and lasted until December 2021.

What stands out about this project is the excellent cooperation, both between the companies of the ERNE Group and with the ARA operational staff and the engineering firm Baerlocher und Partner AG, Lengnau. A big thank you is due to everyone involved.