Cologne Rhine Sewage Tunnel: Project Milestones
Recovered Tunnel Boring Machine: "Henriette" Found in Cologne
As the Cologne Rhine sewage tunnel project progresses, significant milestones have been achieved, with more to come in the near future. Here's an update on the current status and recent developments:
Tunnel Boring Machine "Henriette"
- Completion of Tunneling: The tunnel boring machine "Henriette," named after the Cologne mayor, successfully completed its journey between Cologne-Stammheim and Niehl under the Rhine in August 2025.
- Retrieval and Transport: The retrieval of the 100-ton machine was initially delayed due to a large clay lump and stubborn nuts, but it was finally lifted out of the sewage tunnel and transported away around midnight.
- TBM Specifications: The tunnel boring machine "Henriette" weighs approximately 100 tons, with its cutter head tipping the scales at over 20 tons.
Second Tunnel Construction
- Upcoming Construction: Work on a second tunnel is set to begin soon in Cologne. This development is a crucial step towards the completion of the project.
- Timeline: The second tunnel is expected to be finished by November.
Wastewater Treatment Improvements
- Expanded Capacity: The completion of the new tunnels will allow the full capacity of the treatment plant in Cologne-Stammheim to be utilized.
- Maintenance Efficiency: With three new pipes running through the two tunnels, one pipe can be emptied for maintenance, a task that was not possible with the old Rhine duct.
- Future-Proofing: The additional pipes are a response by the SEB to the expected population growth in Cologne in the coming years, ensuring wastewater management remains efficient and effective.
Environmental Impact
- Reduction of Combined Sewer Overflows (CSOs): The new tunnels will capture stormwater and sewage during heavy rains, preventing untreated sewage from entering the Rhine.
- Improved Water Quality: By diverting excess wastewater to treatment plants, the project significantly reduces pollution levels in the river.
- Enhanced Treatment Capacity: The increased flow capability allows wastewater facilities to operate more efficiently, especially during peak inflow periods.
- Environmental Benefits: The project helps comply with environmental regulations and enhances ecosystem health in the Rhine.
For more detailed, up-to-date specifics such as exact dates or technical specifications, you might consider checking official project reports from the City of Cologne or the managing water authorities.
