Flood Risk Study for Riverside/East Riverside/Lake St. Clair

The City of Windsor (pop. 217,188) will be carrying out a feasibility study to understand the vulnerability of the City’s drainage system to variability in climate conditions and rainfall. The study will focus on quantifying the flood risks to an area of land along Riverside drive, and inland, which is 6 kilometers long and includes 7,481 land parcels and the City’s Little River Pollution Control Plant. The area is at risk of surface flooding due to alterations to the Riverside dike system since its installation in the 1980’s. Surface flooding beyond this flood control infrastructure can overwhelm the City’s sewer system and significantly affect the wastewater treatment plant. Variability in water levels in the Detroit River and Lake St. Clair has left the City of Windsor with the complex engineering challenge of how to protect residents in this area. The current water level trend is returning to that coinciding with the historic flood events of 1973, 1986 and 1998 and is close to historic high levels. Since 2010, the region has experienced a number of extreme rainfall events, which all resulted in reports of widespread flooding. The flood risk is related to a combination of significant rainfall events and high water levels in the Great Lakes system. The study will use the PIEVC protocol, developed by Engineers Canada, to assess the impacts of climate change on drainage infrastructure. The five steps include: 1) Project definition; 2) Data gathering; 3) Risk Assessment; 4) Engineering analysis; and 5) Conclusions and recommendations. Data will be gathered on surface and subsurface conditions and historical and current climate information in order to project the severity and probability of future climate change and flooding events. The risk assessment will determine the severity of climate impacts on the components of the infrastructure; determine the risk tolerance thresholds and identify the higher risk components using projected climate change scenarios. The engineering analysis will determine the existing capacity of the system to mitigate flooding, and will determine the remedial actions that would be required under the projected climate change scenarios to improve resiliency in the study area. A detailed action plan with planning level estimates for construction costs for remedial works in order to reinstate and enhance the flood protection system will be determined in order to protect the community. This will be the first PIEVC analysis of infrastructure in the City of Windsor and will provide an ideal opportunity to use this information alongside of the City’s newly updated Asset Management Framework. This framework looks to embed Climate Change impacts into infrastructure decisions while also providing a methodology to assess against triple bottom line decisions.