Lange Street in Detmold, a city in North Rhine-Westphalia, Germany, and one of the country's most beautiful shopping streets with a substantial number of well-preserved historic buildings, has undergone a comprehensive redesign and wastewater system upgrade.
The overall goal was to enhance the quality of visit and overall experience in the inner-city pedestrian zone by adding new trees, benches, fountains, lighting and paving to improve accessibility.
Credit: Steinzeug-Keramo
This opportunity was also used to upgrade the underground utility infrastructure, including the renewal of the combined sewer and stormwater drainage systems, along with the residential connection pipes.
The project: Complete renewal of utility infrastructure
The city of Detmold put the construction project out to tender across Europe. The engineering firm, Bockermann Fritze, and the landscape architects, Kortemeier Brokmann, were commissioned to carry out the planning, while civil engineering works were carried out by Strabag AG.
Steinzeug-Keramo supplied its vitrified clay pipes for the construction of the underground wastewater infrastructure, utilising its longstanding expertise.
The construction project was divided into three phases, with the first phase completed in 2024. During this initial stage, the 115-metre stretch between the market square and Exterstraße street was prepared for open-cut sewer pipe installation. This involved excavation to create a trench, then laying a gravel bed to provide a stable foundation for the Steinzeug-Keramo vitrified clay pipes, ensuring adequate support and alignment.
Despite the road being only 15 metres wide, half of it remained in use to ensure all shops remained accessible and outdoor dining continued as normal.
In addition to the sewer system, the district heating network and the supply lines for gas, water and electricity were renewed, and empty conduit routes were installed for future or temporary use.
The dual stormwater and sewage system solution
Many of the residential pipe connections were found to be in poor condition and were originally laid across property boundaries, which was remedied as part of the project.
Technicians at Steinzeug-Keramo proposed dual infrastructure for stormwater and combined sewage because it allows for more efficient water management, reduces the risk of overflows during heavy rainfall and ensures better separation and treatment of wastewater.
The company’s wastewater pipe systems made of vitrified clay easily fulfil the extremely high demands of this project, specifically around weight loading. The longitudinal compression resistance of Steinzeug Keramo vitrified clay pipes is 100N/mm2. This ability to endure challenging conditions without deforming ensures the integrity of the drainage system. High chemical and corrosion resistance will also ensure a long lifespan.
Sourced from natural raw materials, Steinzeug-Keramo’s vitrified clay pipes have a service life of over 150 years and are completely recyclable. Every ceramic product from Steinzeug-Keramo contains a minimum of 30% recycled content, making it a pioneering product in terms of circular economy.
In addition, the production process uses green electricity from renewable sources of energy, providing this project with sustainable sewage infrastructure.
The diameters of the newly installed Steinzeug-Keramo vitrified clay pipes were specified to meet the forecast storm surge volumes on the system. The combined sewer was specified to DN 600mm while the stormwater sewer was DN 500 mm. The replaced residential connection pipes that feed into the sewer system will have a standard diameter of DN 150 mm.
Challenging construction site with limited space
One distinctive feature of Detmold’s wastewater system is that the existing combined sewer, constructed in brickwork, was four metres below the surface, while the stormwater sewer was located at a depth of two metres.
The new combined sewer is 115 metres long and forms the low layer of the new infrastructure. The open-cut trench was both narrow and deep, making it impossible for construction vehicles to access. Therefore, the gravel bed was created first, followed by the precise installation of the Steinzeug-Keramo vitrified clay pipes.
Installing vitrified clay pipes required both precise workmanship and carefully planned site logistics, as there was minimal space above ground for storing materials, and access to nearby retail outlets had to be maintained at all times.
The results
The completion of the works using Steinzeug-Keramo vitrified clay pipes has transformed the city of Detmold into a geener, more appealing and accessible shopping area.
These vitrified clay pipes are a long-standing sustainable solution for wastewater systems, as vitrified clay doesn’t corrode, degrade or lose strength over time. Since vitrified clay pipes contain no harmful substances, they can remain in the ground without risk of polluting the surroundings and even outlive the surrounding infrastructure with lifespans exceeding 150 years.
At street level, new seating areas, playground equipment, historical features and easy-to-navigate paths have made the area more enjoyable for everyone. Meanwhile, a long-lasting and sustainable drainage solution has been installed underground to manage water effectively for decades to come.
For more information on Steinzeug-Keramo, visit: www.steinzeug-keramo.com