While Alberta continues to recover from devastating large scale flooding events caused by record setting rainfalls across the province, Ontario can take comfort in knowing it has implemented a system that helps reduce flood damages through effective flood forecasting, flood mitigation works, and managing development in flood plains.   

The most severe flooding on record in Ontario occurred in October 1954 when Hurricane Hazel passed into southern Ontario, killing eighty-one people and causing over $180 million in damages. Following the devastating impact of Hazel, a flood plain mapping and flood forecasting and warning system was established in the province. Ontario’s flood management system is often regarded as an example of good risk management.   Ontario’s 36 Conservation Authorities, local watershed management agencies that deliver services and programs that protect and manage water and other natural resources, work with the Ontario Ministry of Natural Resources under a provincial emergency management framework to deliver a flood management program to help safeguard the homes, belongings, and lives of Ontarians from flooding events.  Conservation Authorities are responsible for monitoring and predicting flood flows and water levels within their watersheds, operating flood control structures such as dams, and disseminating flood messages to local municipalities and agencies.  Flood forecast messages enable Conservation Authorities and Municipalities to prepare for, track, and manage local flooding. Advance warning provides these agencies with the opportunity to put emergency plans into operation, evacuate communities if necessary, and secure property in areas that are more likely to flood.  In parts of the province where Conservation Authorities don’t exist, the Ontario Ministry of Natural Resources provides a flood management program through their District Offices.

In accordance with the Conservation Authorities Act (1946), Conservation Authorities have the ability to restrict development in flood plains.  While some may claim Conservation Authority permitting processes are unnecessarily restrictive, flood management programs delivered by the Conservation Authorities prevent loss of life and an average of well over $100 million per year in reduced flood damages.

“Although Conservation Authorities and our partners have done a good job at minimizing risk, the reality is that flooding remains to be the leading cause of public emergency in Ontario, costing millions of dollars per year in damages” says Kim Gavine, General Manager of Conservation Ontario, the organization that represents the Conservation Authorities. Gavine also outlines that climate change impacts are a significant issue as they create more frequent and more serious flood events, “flooding can no longer be seen as a spring problem” she says, “it’s an issue year round”. 

Conservation Ontario believes that additional investment is needed now to reduce costs later if we hope to minimize the risk and reduce overall cost to the public.  Continued funding is needed for aging dams and dykes that require ongoing preventative maintenance, repair, and replacement.  In addition, supplementary funding is required to update flood plain maps to move from the traditional hard copy maps to modern digital mapping. These modernized maps can be used to update emergency response plans and improve preparedness for future large floods.  Fortunately technology has evolved, significantly reducing the cost to update and maintain flood plain mapping.   The Federal Provincial Floodplain Damage Reduction Program, which historically provided funding for flood plain mapping, needs to be reinstated to update flood plain mapping and associated computer models.  Not only will this information help in preparing emergency response plans but it will also support efforts by Environment Canada to provide improved weather forecasts and weather radar information.

Investment in hazard management is an important underpinning of the economy that can reduce disruption during disasters and return business to normal much more quickly. This is one of the factors that makes Ontario an attractive place to live and do business. Most importantly, this investment will help keep Ontarians safe and reduce impact to them during major floods.

To learn more about flood forecasting and management in Ontario visit Conservation Ontario’s website http://www.conservation-ontario.on.ca/projects/floodstatus.html .


For more information:

Kim Gavine
General Manager
Conservation Ontario
905-895-0716 ext. 231
[email protected]

Dwight Boyd
Director of Engineering
Grand River Conservation Authority
519-621-2763 ext. 2225
[email protected]

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