With walls, berms and raised roads, Fort McMurray is working to keep its river from overflowing

Since the devastating spring floods of 2020 in Fort McMurray, the northeastern Alberta community has been diligently working on enhancing its flood defences against rising rivers. The Regional Municipality of Wood Buffalo (RMWB) officials have stated that Fort McMurray is now better equipped for future floods, thanks to the significant investments made in flood mitigation measures.

James Semple, the manager of RMWB’s project management office, highlighted that $119 million has already been spent on flood mitigation, with an additional $270 million planned for future works. The ultimate goal is to prepare the community for another one-in-100-year flood, similar to the 2020 event, as well as a one-in-200-year flood, where the river levels could rise even higher.

Fort McMurray’s vulnerable location at the confluence of the Athabasca and Clearwater rivers makes it prone to ice jam flooding during the spring thaw. Nadia Kovachis, a river hydraulics and ice engineer with Alberta River Forecast Centre, explained that the unique geography of the area encourages ice jam formation downstream of Fort McMurray.

The 2020 flood, caused by a massive 25-kilometre ice jam on the Athabasca River, resulted in significant damage and forced thousands of residents to evacuate. Post-flood engineering reports revealed shortcomings in the municipality’s flood mitigation system, prompting a renewed focus on enhancing the existing infrastructure.

Recent approvals by the RMWB council have paved the way for structural mitigation works between the Clearwater River and Clearwater Drive, marking the final phase of downtown Fort McMurray’s flood mitigation efforts. The planned construction includes earth berms and retaining walls, with the Heritage Shipyard being relocated to accommodate the infrastructure.

Semple emphasized that Fort McMurray’s flood mitigation system comprises a combination of berms, walls, and road elevation adjustments to reduce the risk of flooding in susceptible areas. The construction of man-made berms, capable of withstanding significant water level rises, is a key component of the mitigation strategy.

Erin Sieger, the RMWB’s director of emergency management, highlighted the proactive approach taken by the municipality in preparing for potential flood seasons, starting as early as March. Collaboration with river forecasters and stakeholders plays a crucial role in monitoring and responding to flood risks.

Kovachis stressed the unpredictability of ice jam flooding events, with factors like snowpack thickness and rapid temperature changes influencing the severity of floods. The ongoing efforts to strengthen Fort McMurray’s flood defences reflect a commitment to safeguarding the community against future natural disasters.