Integrating Climate Change into Municipal Watershed Management in Ontario

Rachel M. Gregg
Posted on: 6/05/2013 - Updated on: 3/02/2020

Posted by

Rachel Gregg

Project Summary

The Toronto and Region Conservation Authority (TRCA) is engaged in multiple climate change projects focused on integrating adaptation into long-term planning for natural and built systems. This includes developing resources and networks to support knowledge exchange between practitioners and conducting assessments to evaluate the challenges presented by global climate change.


Observed climatic changes in Ontario include increases in temperatures and altered precipitation patterns; these changes are expected to continue and increase in frequency and intensity over time. These changes will have cascading effects on water resources in the province, including an increased need for drinking water source protection, water allocation planning, water quality monitoring, and improved management of stormwater systems, dams, and reservoirs. TRCA has worked on watershed management and sustainability issues in Ontario since the 1950s and has integrated climate change adaptation and mitigation measures into its efforts. Example adaptation initiatives include the Mainstream Project, the Climate Consortium for Research Action and Integration, and a vulnerability assessment of some of the public water resources infrastructure under its purview.


Mainstream: The National Water Adaptation to Climate Change Project

The Mainstream project, funded through the Ontario Regional Adaptation Collaborative, was created to collect and present information on climate change and water resource management in Canada. Partners include TRCA, the Canadian Water Resources Association, the Canadian Foundation for Climate and Atmospheric Sciences, the Institute for Catastrophic Loss Reduction, Conservation Ontario, the Ministries of Natural Resources and Environment, York University, ESSA Technologies, North Arrow Research, EBNFLO Environmental, and AquaResource/Matrix Solutions. Activities include:

  • Providing a Mainstream Forum for networking and knowledge exchange on climate adaptation.
  • Creating a compendium or database of climate change adaptation resources and tools related to extreme storms and flooding events;
  • Writing a status report on adaptation in water resources management in Canada.

The Mainstream Forum was held March 22-23, 2012 in Toronto. The stated objectives of the forum were to:

  • Provide learning opportunities for new ways of thinking about water adaptation;
  • Reflect upon the current state of practice and share knowledge on water adaptation projects;
  • Showcase a diverse range of projects led by Forum participants;
  • Stimulate discussion to identify:
    • Water adaptation knowledge needs of practitioners (e.g., engineers, scientists, policy analysts, project coordinators, planners, and educators);
    • Opportunities for dissemination of knowledge and collaboration towards the mainstreaming of adaptation.
  • Contribute to:
    • A national compendium of knowledge on water resource adaptation to be used by practitioners; [and]
    • A briefing document on the state of and opportunities for advancing water adaptation across Canada. (Forum Results Report 2012).

The compendium is geared toward water resources practitioners from municipalities, watershed organizations, private sector groups, advocacy groups, and provincial/territorial agencies in Canada and around the world. Its purpose is to provide information and training on climate change adaptation as it relates to water resources. The website was launched in June 2012 at
Climate Consortium for Research Action and Integration (CC-RAI)

The CC-RAI is a partnership between the TRCA and York University to coordinate research and provide resources and tools to practitioners in Ontario and the Great Lakes region.

Public Infrastructure Vulnerability Studies

The TRCA and Engineers Canada conducted a vulnerability assessment of two dams that TRCA operates using the protocol developed by the Public Infrastructure Engineering Vulnerability Committee (PIEVC). The TRCA applied this protocol to determine the ways in which the dams might fail due to climatic changes, including an engineering analysis of infrastructure capacity to handle increased water flows in a changing climate. In addition to the PIEVC protocol, the partners applied climate models, a climate trend analysis, a literature review, and expert opinion.

Outcomes and Conclusions

TRCA has engaged in a number of adaptation projects, including the three highlighted here. Their philosophy is to integrate climate change into the day-to-day practices of their partners and associated stakeholders. Through the Mainstream Project, TRCA and its partners have created a national water resources database of adaptation tools that supports open information exchange between practitioners.


Gregg, R. M. (2012). Integrating Climate Change into Municipal Watershed Management in Ontario [Case study on a project of Toronto and Region Conservation Authority]. Product of EcoAdapt's State of Adaptation Program. Retrieved from CAKE:… (Last updated October 2012)

Project Contact

Harris Switzman
[email protected]

Affiliated Organizations

Formed in the aftermath of Hurricane Hazel, TRCA has a strong history in watershed management and leadership in applying sustainability practices.  Today, we own more than 40,000 acres of land in the Toronto region, employ more than 400 full time employees and coordinate more than 3,000 volunteers each year.

The quality of life on Earth is being determined in the rapidly expanding city regions.  Our vision is for a new kind of community, The Living City, where human settlement can flourish forever as part of nature's beauty and diversity.