Enabling Trenchless Rehabilitation of Aging Urban Water Mains

Project:​ Urban Water Main Rehabilitation
Challenge:​ Rehabilitating aging and leaking underground water mains beneath dense urban areas with minimal social and economic disruption from large-scale trench excavation.
HDPE Solution:​ The project employed trenchless technology​ using HDPE pipes. The primary method was slip-lining, where a new, smaller-diameter HDPE pipe is pulled or pushed through the existing host pipe. The flexibility and smooth bore of HDPE make it ideal for this technique. In more complex scenarios, a method called modified pipe bursting​ can be used, where a bursting head fractures the old pipe while simultaneously pulling in a new HDPE pipe of the same or larger diameter .
Results:​ This approach dramatically reduces excavation, leading to lower restoration costs, shorter project times, and less inconvenience to the public. A reported case in China’s Dagang Southern Oilfield using HDPE rehabilitation technology showed the repaired pipeline operated normally for nearly five years, extending the service life significantly, with maintenance costs at only 58% of full replacement costs . The corrosion resistance of HDPE also improves water quality compared to relining with traditional materials.