Beautiful section with fine white gravel along the Cologne Randkanal (Pulheim). Very good and fast to navigate.
Source Wikipedia (April 2020):
The canal is mainly used to maintain water in the Rhenish open-cast lignite mines near Frechen. In addition, it supports the drainage of the Rhein-Erft district and takes in the treated wastewater from the sewage treatment plants in Pulheim, Frechen, Hürth and the Cologne districts of Esch, Auweiler, Pesch and Widdersdorf. The city of Dormagen and Ineos Cologne in Cologne-Worringen have direct discharge rights. The southern edge canal now only takes in rainwater in the southernmost part at the old sewage treatment plant in Hermülheim during heavy rain.
Treated wastewater from the parts of Cologne and the Rhein-Erft district further east is discharged through the southern outfall to the Rhine near Rodenkirchen. The southern outfall closes the sewage ring around the Cologne city area on the left bank of the Rhine.[1]
In addition to the discharge of treated sewage from the municipalities in the Cologne Bay, the edge canal has also been used for flood protection on the Erft since its renovation in 2010–2015. The Erft flood canal can be partially dammed by a weir near the Kerpen district of Horrem-Götzenkirchen and corresponding amounts of water can be diverted into the feeder channels to the Götzenkirchen pumping station and through the Ville tunnel into the edge canal and thus into the Rhine.