Alternate Sewer Rehabilitation Methods: EXpanding the Toolbox

Over the past few years, Citizens Energy Group has been reexamining the means and methods used in the vast majority of its sewer rehabilitation program. This reexamination has led to a pilot project utilizing the proprietary fold and form technology – EX lining system. The EX lining system heats polyvinyl chloride (PVC) pipe such that it is malleable, and then rapidly inserts that heated pipe into a cleaned sewer. The inserted pipe is then pressurized, taking the form of the host pipe. The PVC liner then cools and hardens, retaining its original circular shape, creating a new pipe within the existing pipe. The EX system cost less than curried in place pipe (CIPP), but does have limitations related to pipe diameter and maximum segment length when compared to CIPP.This paper presents an alternative approach to small diameter sewer rehabilitation methods that utilities can utilize to extend the useful lifespan of small diameter sewers, specifically in residential neighborhoods. Using a case study from the east side of Indianapolis, Miller Pipeline’s proprietary fold-and-form sewer rehabilitation (often referred to as close-fit pipe rehabilitation) EX product provided a comparable solution for a targeted I&I mitigation project area. The project area, project background, scope and cost of the project will be discussed along with the installation procedures. The overall advantages and disadvantages will also be discussed and compared to CIPP to accurately gauge this fold and form product.