In 2019, the Weber Basin Water Conservancy District installed the first tight-fit HDPE liner for a large diameter drinking (culinary) water pipeline in the state of Utah. The project included rehabilitation of 1.5 miles of 30-inch and 27-inch diameter AWWA C303 "Bar-wrapped" and non-standard non-cylinder reinforced concrete drinking water pipeline originally installed in 1955. The design basis was carried out utilizing a “partially deteriorated” host pipe condition for the majority of the alignment with a fully-deteriorated liner design in select locations based on findings of hydraulic modeling and CCTV observations.Pressures in excess of 100 psi, steep slopes greater than 40 percent through a valley, and a narrow corridor within an established residential community were some of the construction challenges. Successful rehabilitation of the 9 MGD pipeline was accomplished through careful collaboration between owner, engineer and construction team. Custom proofing pigs were fabricated to detect and grind joint defects, and a highly successful community relations campaign was implemented for stakeholders along the alignment.This paper will discuss the planning, installation, and testing of the liner from the perspectives of the engineering team and specialty liner installers with emphasis on engineering considerations during construction, and challenges encountered during installation, and lessons learned.This case study is intended to be a useful reference for pipeline designers, city asset managers, and contractors considering similar rehabilitation projects.
展开▼
