Toronto: Transport Sector Climate Risk Assessment

by Corrine Rodriguez


Toronto’s transportation network includes four major highways, multi-modal railway facilities, the Port of Ontario, and Pearson International Airport. Toronto also boasts the second largest public transit system in North America comprised of bus, subway, rapid transit, and streetcar lines operated by the Toronto Transit Commission (TTC). Greater Toronto and Hamilton Area residents are served by GO Transit, the regional train and bus service, which also links to the TTC. On a typical workday, the TTC carries 1.5 million passengers (Toronto Transit Commission, n.d.). Moreover, 96% of GO Transit’s train ridership and 70% of its bus ridership travel to and from the City of Toronto (GO Transit, n.d.).


Climate Risks
A climate risk assessment (Mehrotra et al., 2009) demonstrates first that recent extreme weather events and growing climate variability have exposed the vulnerability of Toronto’s transportation infrastructure to climate change impacts (Andrey and Mills, 2003), Ligeti et al and a forum conducted by the Toronto Urban Climate Change Network (2009) cite the following as potential climate impacts and risks to the transportation sector:


Climate Impact Physical Infrastructure Operations
Higher temperatures (e.g., heat waves, power outages) Asphalt rutting, pavement damage, Traffic congestion, road travel and electricity-dependent modes of transportation (e.g., streetcars, trains, etc.) hampered
Increased poor air quality (e.g., smog) Traffic congestion
Increased freeze-thaw cycles Potholes and other road disrepair, damage to pavements and runways Flight delays and cancellations
Increased intensity and frequency of extreme weather events (e.g., heavy rainfall, floods) Damage to roads, bridges and culverts, sewers, parking garages, etc. Traffic control management, flight delays and cancellations,
Lower inland water levels Disruption of shipping activity


Mitigation and Adaptation Responses

Mitigation Measures

The Climate Change, Clean Air and Sustainable Energy Action Plan (2007)established reduction targets for GHG emissions in the Toronto urban area from 1990 levels of 22 million tons per annum to 6% by 2012 (Kyoto Protocol targets), and ultimately to 80% by 2050 (City of Toronto, 2008). One of the city’s well-developed mitigation responses to achieve these goals is the Sustainable Transportation Implementation Strategy (STIS). The STIS focuses on the passenger transportation sub-sector and sustainable transportation initiatives for the short- and long-terms.

The STIS has a three-pronged approach. First, there are behavioral-based proposals, which include promotion of car-sharing programs, the introduction of road-user charges, and the construction of commuter parking facilities. Second, there are proposals to change the urban form through land use and zoning. They include the creation of temporary and permanent pedestrian zones and streets, pavement narrowing, the expansion of major bike trail corridors, and extended peak hour parking restrictions. Third, there are technological approaches involving the utilization of Intelligent Transportation Systems (ITS), which aim to improve system efficiency by providing travelers with information that will increase their mobility (City of Toronto, 2007a, 2007b, 2007c, 2008). Examples of ITS technologies include Highway 401’s compass freeway management system and Highway 407’s intelligent toll collection (Woudsma, 2003).

Each of the mitigation strategies noted here may contribute significantly to Torontonian’s quality-of-life, enhance productivity, and make the city more attractive. However, according to Mehrotra et al. (2011), they do not sufficiently reduce the climate hazard factor for the city. Risk reduction at the local level should include adaptation responses.

Adaptation Measures

Toronto’s adaptation responses are not as comprehensive as its mitigation responses. This may be due, in part, to a dearth of research on climate change adaptation for the transportation sector as a whole (Infrastructure Canada, 2006). Furthermore, transportation infrastructure decisions do not generally incorporate climate change adaptations (Infrastructure Canada, 2006). However, Toronto does employ some adaptive measures to maintain its roads, bridges, and other infrastructure. For example, it utilizes a life-cycle costing, system for road repair, which requires that roads be fixed as necessary to avoid costly maintenance in the future, (City of Toronto, n.d.). This strategy is cost-effective as it extends the useful life of roads, thus delaying costly reconstruction. Other adaptive measures being utilized include use of new materials and technologies, reviewing standards and practices, employing green design standards, as well as disaster and emergency management (TUCCN, 2009).

Policy Recommendations

Toronto should focus on programmatic adaptation strategies that will reduce its risk over the long-term. Strategies might include: 1) regularly reviewing and updating design and engineering codes, standards and practices to reflect changing climate extremes (TUCCN, 2009); and 2) developing a working group comprised of planners, engineers, NGOs, local and regional transportation authorities, and other stakeholders to develop a transportation infrastructure master plan. Third, federal fiscal transfers are needed to support local adaptation planning.



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This article is a product of Professor Shagun Mehrotra’s Climate Change and Cities class. Views expressed are entirely those of the individual author.