Management of inflow and infiltration in new urban developments By Ted Kesik
February 2015
Abstract
This study commissioned by the Institute for Catastrophic Loss Reduction attempts to provide a best practices guide for the management of inflow and infiltration (I&I) in new urban developments. It is intended to serve as a knowledge map of sorts connecting relevant and authoritative sources of information. While the focus of the study is the Greater Golden Horseshoe, the findings are extensible to other regions of Canada and particularly relevant to areas experiencing rapid continued growth.
A premise of this study is that I&I in sanitary sewer systems is a barometer of the care and diligence exercised by public works organizations, and a direct reflection of the corporate culture of a municipal and/or regional government. After having put men on the moon and safely bringing them back almost half a century ago, it is not unreasonable to expect fully engineered municipal infrastructure to consistently achieve high performance. However, it is important to appreciate high performance infrastructure comes at a cost that comprises the initial expenditure and the ongoing operational and maintenance costs over the life cycle of the infrastructure asset. Willingness to pay combined with political will are viewed as among the most significant obstacles to delivering sustainable infrastructure to Canadians.
Research conducted by way of literature review and interviews with experts indicates virtually all of the prerequisite knowledge and expertise needed to effectively manage I&I in sanitary sewer systems exists today. However, it is widely dispersed among numerous organizations and has yet to be integrated and consolidated. Without a consistent knowledge base that is readily accessible, not only does each municipality have to develop its own standards, guidelines and protocols, but it is also difficult to effectively conduct training and education of design professionals, asset managers and skilled trades. It is time for municipal infrastructure to evolve from a collection of local prescriptive measures to an integrated system of performance-based technologies. Some jurisdictions have embraced this challenge and are demonstrating considerable success in achieving performance objectives.