Munich Sewer Rehabilitation

Project context

The targeted sewer segments ran beneath listed-heritage streets in central Munich where excavation was permanently forbidden. The combined sewer carried sustained flow that could not be bypassed for extended periods, and adjacent utilities — gas, telecom, district heating — were less than 1 meter from the sewer crown. Conventional open-cut was technically and politically impossible.

Our solution

Huatao supplied UV-CIPP felt liners impregnated with sanitary-grade resin, sized to DN300, DN400, DN600, and DN800 across the 18 segments. Sectional CCTV inspection mapped defect locations and confirmed dimensional compatibility prior to liner production. UV light trains traversed each segment in a continuous cure cycle, delivering 50-year design service life with zero excavation. Local contractors completed pre-installation cleaning using our pipeline dredging robots and slurry pumps.

Outcomes

• 3,200 meters rehabilitated with zero pavement excavation
• 11-week project completed on schedule with year-round construction capability
• Zero traffic closures on listed-heritage surface streets
• 50-year design service life confirmed via post-cure mechanical testing
• Sanitary-certified resin compliant with German DIN drinking-water-adjacent standards
• Zero adjacent-utility incidents during installation