Underground Construction Technology International Conference & Exhibition

In early 2009, officials in King County, WA, addressed a hydrogen sulfide (H2S) problem in a nearly half mile stretch of concrete sanitary sewer. Rehabilitation was needed near the Lake Hill Interceptor. Engineers chose the cured in place pipe (CIPP) technology to address the corrosion problem and restore structural integrity. The project, totaling $2.6 million, rehabilitated 513 lf of 36", 1,472 lf of 42", 496 lf of 48", and 135 lf of 54" concrete sanitary sewers. While the client originally specified water inversion and water cure, they opted to go with the more environmentally friendly air inversion steam cure (AISC) process when the project was implemented. This allowed both savings for both energy and water resources. In fact, AISC uses roughly 98 percent less water than the traditional water cure. making it an excellent option in areas with scarce resources.