The Urban Stream Syndrome: causes, failures, and the search for a cure

Full Name: Elli Papangelaki

Academic Affiliation: University of Waterloo

Position: PhD Candidate

Abstract (max 250 words): As urbanization expands in Canada and globally, rivers undergo many rapid and significant changes. The most consequential of these changes are an increase in the quantity of water delivered to the river, and a severe decline of water quality. Together, these shifts bring an increase in the magnitude and frequency of flooding, dangerous and costly erosion problems, and a deterioration of river ecology. These universally observed trends are symptoms of what has been coined the ‘urban stream syndrome’. River restoration refers to a large range of modifications to rivers and their watersheds aimed at mitigating symptoms of the urban stream syndrome and includes activities such as the construction of stormwater ponds, vegetating banks and complete channel reconstruction. Unfortunately, most restoration projects fail within 5-10 years of implementation, and have been unable to improve the stability and ecology of rivers. This is significant, because river restorations projects cost billions of dollars annually, and damage costs due to erosion and flooding have not diminished. This failure is largely attributed to a lack of scientific context for restoration projects driven by a poor understanding of the mechanisms behind river change. This research project explores the physical mechanisms behind river change and the ways in which current restoration practices impact river systems through hydraulic, sediment transport, and ecological analyses. The goals of this project are to increase understanding of the processes that drive channel change in the context of urbanization and river restoration, and to provide insights for improved future management practices.