Waste water treatment in South Essen has been completely re-structured by rebuilding the sewage treatment plant Essen-Süd and closing the sewage treatment plants in the Essen suburbs of Rellinghausen, Steele, Heisingen, and Werden. Instead of those decommissioned plants, pumping stations combined with storm water overflow tanks or sewers with storage capacity and overflow were built, transferring the waste water to neighbouring sewage treatment plants.
The sewage treatment plant Essen-Süd now accepts waste water from the old plants in Rellinghausen and Steele; sewage from Heisingen is pumped to Kupferdreh and sewage from Werden, to Kettwig. Thus, the future of waste water disposal in South Essen has been guaranteed for both residential and commercial estates.
Pumping station Essen-Steele
Since late 2005, waste water from Essen-Steele has been transferred to the sewage treatment plant Essen-Süd via a new pumping station. This building, which is round for static reasons, is 20 metres wide and 13 metres deep, with most of it installed underground. Only the large openings for pump assembly and the building housing the electrical switchgear can be seen above ground.
Six pumps convey the sewage of around 67,000 inhabitants at a delivery rate of 680 litres (corresponding to three to four bathtub fillings) per second.
Pumping station Essen-Rellinghausen
As part of the re-structuring process and in order to connect with the sewage treatment plant Essen-Süd, a new transfer pump station had to be built in Essen-Rellinghausen. From here, waste water has been conveyed to the sewage treatment plant Essen-Süd since mid-2005.
Considerable operational re-organisation was required for building the pumping station. The first step was to build a provisional installation next to the existing pumping station. For this purpose, a shaft of 2.40 metres in diameter made of prefabricated components was used to install three pumps and create an exposed connection with the existing pressure pipeline. After dismantling the old pumping station, its new successor could be built in a roughly 12-metre-deep excavation pit. It houses six pumps which convey waste water via two pressure pipelines to the inlet canals leading to the sewage treatment plant Essen-Süd. One feature of this system is a 500-metre-long, walk-in pipe duct underneath a busy road junction.