Understanding and Assessing Impacts
This document was produced as part of a collection of natural infrastructure case studies in Canada to explore opportunities and barriers in accelerating the implementation of natural infrastructure as an adaptation measure and resilience strategy. Calgary’s major flooding event in 2013 is the main inciting event that highlighted the need for a suite of flood reduction strategies in the region. The flood event displaced thousands of families, disrupted and destroyed businesses, damaged public and private property, and claimed four lives. Flood damages were more than $5 billion across Alberta and an estimated $400 million to the City of Calgary’s infrastructure. Informed by the fifth generation Canadian Regional Climate Model, the article notes that climate change is increasing the likelihood of rainfall in the region and adding to flood risks. At the same time, wetland loss has been a persistent issue in the Bow River Basin. According to the provincial government, in Alberta’s populated areas 64 percent of wetlands have already been lost and the region continues to lose wetlands at a rate of 0.3-0.5 percent per year. In the City of Calgary specifically, losses are in the range of 90 percent. The loss of 133,000ha of wetlands in Alberta over the past 40-60 years has resulted in approximately 379,000,000 m3 of lost water storage capacity. By reducing the ability of the landscape to store water, the loss of wetlands results in increased flow and volumes downstream following rainfall events, exacerbating flood risk.