Construction of the main outlet
On behalf of Stadtwerke Offenbach's Stadtservice, Stadtwerke Offenbach has built the Main outlet on the banks of the Main at the level of the former Clariant site. This is the end of a new sewer that relieves the combined sewer during heavy rainfall and discharges heavily diluted combined water directly into the Main.
The mixed water, which has been discharged during heavy rain since 2022, comes from the stormwater overflow structure in Kettelerstraße. The overflow sill is designed in such a way that the wastewater is mixed with a lot of rainwater when it flows into the Main. Both the depth and the shape of the outlet ensure that the water flowing out later does not impair navigation or damage the banks.
Crossing under the Maindamm: A challenge from an engineering perspective
The canal had to be routed under the Maindamm. From an engineering point of view, this is a challenge. The pipe jacking method was used: A large, remote-controlled drilling head clears the way underground for the new pipes with a diameter of two meters.
Status of the work
The Main outlet itself was completed at the end of 2021. It is part of a major project to drain rainwater from Bieber and the connected areas below via this Main outlet in the event of heavy rainfall. Now only 1,000 meters of new sewer are missing, which will run along Mühlheimer Straße between Karl-Herdt-Weg and Kettelerstraße. It is expected to be completed by the end of 2024.