By Roger Rempel and Joel Nodelman
Climate change impacts are being observed in every region of Canada, with increased frequency and intensity of hurricane events in the Atlantic region, ice storms in Ontario and Québec, more tornadoes in the Prairies, severe flooding events in Toronto and southern Alberta, shorter ice road seasons in the North, and increased intensity and frequency of “Pineapple Express” extreme precipitation events on the Pacific coast.
Canadian engineers designing critical infrastructure are faced with a growing challenge. We must design, build and operate infrastructure systems that are resilient to the environments where they are intended to operate, while satisfying our obligation as engineers to protect the public’s health and safety.
The public often takes for granted that our systems will function as designed for the operating environments they were intended for. Meanwhile, changing climate conditions in Canada are challenging these systems on an ongoing and growing basis. These systems can fail, with the potential for economic disruption and loss of life.
The engineering profession must identify ways to address our evolving understanding of the hazards presented by a shifting climate. We must also provide tools to professional engineering practitioners to ensure safe and reliable infrastructure system designs.
Issues with existing codes and standards
Most of the infrastructure that exists today was designed using values derived from historical climate data. This practice is based upon the premise that the average and extreme conditions of past decades will also hold throughout the decades to come.
As long as our climate remains stable, defining the “envelope” for a design’s operating environment using historical climate data, is an approach that has worked reasonably well. Given a stable, consistent climate, we could design for known conditions over an expected service life. We could be confident that our design would be resilient enough to function properly in that intended operating environment. Engineers have applied this approach because it allowed consideration of climate design values for flooding, rainfall, temperature and others, over different return periods and historical extremes for a given location.
But, how valid can this approach be when our climate begins to shift and move away from these historical ranges? Could we be leaving unattended risk “on the table” within the gap between historical and future climate conditions? If the vast majority of our engineering codes and standards do not yet include consideration of a shifting climate that no longer adheres to historical patterns, then who must manage the risks induced by this wider range of conditions?
The answer is professional engineers. Engineers Canada, the national organization representing regulatory associations that license the engineering profession across Canada, recognize that effects of a changing climate will require infrastructure designs to be revisited to improve safety and protection for Canadians.
Engineers Canada worked with Natural Resources Canada to develop partnerships with municipal and provincial government owners of public infrastructure. The Public Infrastructure Engineering Vulnerability Committee (PIEVC) and a best practices framework for detailed assessment of climate vulnerability of public infrastructure, known as the PIEVC Protocol, were both established.