Environmentally friendly rehabilitation of drinking water pipelines in Münster – with high Installation speed through the nature reserve

The transport of drinking water from the waterworks in Münster is now carried out by fully welded egeplast pipe systems. With the rehabilitation of the old drinking water pipelines, the capacities of the drinking water and surface water pipelines of the Hohe Ward waterworks were also to be expanded. In doing so, Stadtnetze Münster faced the challenge of ensuring an environmentally friendly Installation when crossing a nature reserve. They opted for 20-meter pipe sections, which allowed for a high Installation speed and reduced costs.

Between early 2024 and mid-2025, in the Hiltrup district of Münster, old cast iron pipes were replaced by almost 5 km of modern PE drinking water pipes between the Hohe Ward waterworks and the Hiltruper See parking lot. The client is Stadtnetze Münster, which commissioned Ludwig Freytag as the construction company and pipe layer and selected the egeplast egelen PE 100-RC drinking water pipe as the pipe system.

The starting point for the extensive rehabilitation was the fact that the old cast iron pipelines from 1906 had reached their maximum service life. Especially at the hemp-sealed connection points, there were increasing leaks and drip leakages. In addition, an expansion of the capacities of the Hohe Ward waterworks had to be considered when planning the new pipeline system. Among other reasons, for cost considerations, a fully welded pipe variant was chosen, which was installed in 20-meter sections using open-trench construction. This reduced the number of welded connections and achieved a high Installation speed.

However, a railway line had to be crossed and a nature reserve traversed along the route, which made precise planning and work steps more important. Below the railway line, new steel protective pipes were pre-pressed, into which the new PE-HD pipes were pulled. For this purpose, walk-in concrete shaft structures were installed on both
sides of the railway line, in accordance with railway specifications, for visual inspection of the newly installed PE-HD pressure pipes. The construction phase for crossing the nature reserve was continuously monitored by ecologists to ensure a standard-compliant and environmentally friendly Installation. Among the special requirements was that all equipment and machinery had to be operated with bio-oil. This requirement increased the complexity of the construction project, especially for pressing equipment, where this is usually not the case.

After almost one and a half years of construction, the project was completed in summer 2025. The pipes now transport water from the Dortmund-Ems Canal to the Hohe Ward waterworks. After multi-stage treatment, the water is fed into Münster’s drinking water network.