Grant: Strategic Projects - Group

Utility managers in Toronto, Hamilton, Kingston and other communities are actively assessing, rehabilitating and replacing water & sewer pipelines to address the current infrastructure renewal cycle, so we continue to enjoy the benefits of clean water for our homes, industries and businesses, and wastewater removal for treatment. Budget limits are placing renewed emphasis on avoiding unnecessary costs associated with water loss from leaking pipes, and ingress of groundwater into sewers. New technologies have been developed to assist with pipeline rehabilitation, like cured in place polymer liners that can reseal leaking pipes and restore structural stability at lower initial cost than 'cut and cover' pipe replacement. However, key knowledge gaps create substantial challenges for consulting engineers advising on specific projects, and significantly magnify the 'new technology' risks perceived by city engineers and others charged with public safety, - The stability of existing pipes is not well understood, so decisions to repair or replace are often made using visual or other qualitative assessments; when better pipe inspection data is available, pipe strength models for cast iron, concrete and clay pipes do not explicitly consider deterioration- The long term failure mechanisms for cured in place polymer liners, their durability and expected service lives have not been established, so consultants & utility managers do not know how long these repairs will last- Spray-on liners are being developed for maintenance holes (MH), but little is known about the liner failure modes, the importance of bond, and sprayed liner durability (no rational procedures are available to choose liner thickness, and the impact on bond of surface cleaning & roughening of the old MH is uncertain)- Past joint leakage issues need to be eliminated in new pipes, by identifying factors controlling leakage.Using unique buried pipe & polymer durability test facilities, Moore, Brachman, Hoult and 8 PhD students will undertake seminal experimental work & analyses to study & address these challenges. The project outcomes can be incorporated into standards, practice guidelines, & specifications for use by industry partners & others.