Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods SOCIAL IMPACT REDUCTION DURING THE JUNE 2013 ALBERTA FLOODS: Using HAZUS Canada to estimate social impact reduction during the June 2013 Alberta floods Ryan Reynolds, Ph.D. Candidate University of Calgary Photo: BBC News Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods

A SIMPLE QUESTION? At a adults-only evening at the Telus Spark science centre I asked a City engineer who was giving a public talk about the floods what I thought was a simple question: “What would have been the impact on those living downstream of the Glenmore Dam if the City of Calgary had not drawn down the reservoir prior to the floods?” Turns out, it was not so simple a question… At a adults-only evening at the Telus Spark science centre I asked a City engineer who was giving a public talk about the floods what I thought was a simple question: “What would have been the impact on those living downstream of the Glenmore Dam if the City of Calgary had not drawn down the reservoir prior to the floods?” Turns out, it was not so simple a question… Photo: Ray Wong Photo: Teddy Kwok (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods FINDING AN ANSWER Finding an answer would involve several City engineers, one City manager, two graduate students, and several different modeling tools We agreed to work together and present our findings at the upcoming Canadian Dam Association conference … only 5 months away! HAZUS Canada, while still in beta, was the best tool to perform the modeling we needed to do in our tight timeline Finding an answer would involve several City engineers, one City manager, two graduate students, and several different modeling tools We agreed to work together and present our findings at the upcoming Canadian Dam Association conference … only 5 months away! HAZUS Canada, while still in beta, was the best tool to perform the modeling we needed to do in our tight timeline Photo: Ray Wong Photo: Teddy Kwok (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods THE FLOODS Photo: Ray Wong Photo: Ryan L. C. Quan (Open Commons)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods DAYS “IT RAINED FOR DAYS”  The bulk of precipitation fell between June 19 and 22  Areas along the Bow, Elbow, Highwood, Little Bow, Red Deer, Sheep and South Saskatchewan rivers were impacted by overland flooding  Of particular interest to Calgary are the Bow and Elbow Rivers, which converge in the heart of the city  The bulk of precipitation fell between June 19 and 22  Areas along the Bow, Elbow, Highwood, Little Bow, Red Deer, Sheep and South Saskatchewan rivers were impacted by overland flooding  Of particular interest to Calgary are the Bow and Elbow Rivers, which converge in the heart of the city Photo: Ray Wong Photo: Ryan L. C. Quan (Open Commons) Source: AESRD, 2014

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods CANADA’S COSTLIEST NATURAL DISASTER  Estimate of insured losses by the Insurance Bureau of Canada: $1.7 Billion  Total damage estimate by the Province of Alberta: $6 Billion  Number of Calgarians forced from their homes as estimated by The City of Calgary: 110,000 persons  Estimate of insured losses by the Insurance Bureau of Canada: $1.7 Billion  Total damage estimate by the Province of Alberta: $6 Billion  Number of Calgarians forced from their homes as estimated by The City of Calgary: 110,000 persons Photo: Ray Wong Photos: Ryan L. C. Quan (Open Commons), Sande Dalton, and Sarah Skett

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photos: Ryan L. C. Quan (Open Commons), Sande Dalton, and Sarah Skett Source: Public Safety Canada, 2014

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photos: Ryan L. C. Quan (Open Commons), Sande Dalton, and Sarah Skett Source: Public Safety Canada, 2014

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Glenmore Reservoir Downtown Core Photo: The City of Calgary Glenmore Dam Elbow River Bow River Elbow River

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: Ryan L. C. Quan Peak Inflow: 1240m 3 /s Peak Outflow: 700m 3 /s

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Hazus Predicted 1:100 Flood vs. Observed ConditionsExtent of June 2013 Flood Waters along Elbow River Observed conditions along the Bow and Elbow Rivers as derived from aerial photographs and high water marks taken following peak flow conditions

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: skinnybrager (Flickr) OUR APPROACH

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: skinnybrager (Flickr) OUR APPROACH Two approaches to social impact modeling: 1. HAZUS, level 1 analysis 2. Custom dasymetric GIS model  Residential building centroids  Civil census community level

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods HAZUS Predicted 1:100 Flood vs. Observed Conditions Areas in red were flooded in 2013 and did not appear in the Base Case HAZUS model. Areas in grey were not flooded in 2013 but do appear in the Base Case HAZUS model.

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: Ryan L. C. Quan Peak Inflow: 1240m 3 /s Base Case Scenario Outflow: 700m 3 /s No Drawdown Scenario Outflow: 820m 3 /s

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Hazus Predicted 1:100 Flood vs. Observed ConditionsComparison of Base Case and No Drawdown Scenarios The No Drawdown scenario (red) extends beyond the Base Case scenario (blue) covering an additional 60 ha

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: Ray Wong (Flickr) RESULTS

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods RESULTS Comparing the No Drawdown scenario to the Base Case Scenario : Difference in extent:  Total: + 600,000 m 2 (60 ha)  Residential: + 217,000 m 2 (20 ha) Comparing the No Drawdown scenario to the Base Case Scenario : Difference in extent:  Total: + 600,000 m 2 (60 ha)  Residential: + 217,000 m 2 (20 ha) Photo: Ray Wong Photo: Ray Wong (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Photo: Ray Wong Photo: Ray Wong (Flickr) HOUSEHOLD IMPACTS

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods EMERGENCY FACILITIES IMPACTED Photo: Ray Wong Photo: Ray Wong (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods SOCIAL FACILITIES IMPACTED Photo: Ray Wong Photo: Ray Wong (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods VALIDATION OF HAZUS While there were some issues, the HAZUS Base Case (1:100) flood model fit the observed conditions reasonably well Where flood mitigations were not in effect (e.g., berms, sandbags, etc.) Where flood mitigations were not in effect (e.g., berms, sandbags, etc.) Backwards flow up rainwater drainage in several areas not predicted by HAZUS Backwards flow up rainwater drainage in several areas not predicted by HAZUS No measurements of goodness of fit have been performed: No measurements of goodness of fit have been performed: Too many variables to account for Too many variables to account for Data issues with observed conditions Data issues with observed conditions While there were some issues, the HAZUS Base Case (1:100) flood model fit the observed conditions reasonably well Where flood mitigations were not in effect (e.g., berms, sandbags, etc.) Where flood mitigations were not in effect (e.g., berms, sandbags, etc.) Backwards flow up rainwater drainage in several areas not predicted by HAZUS Backwards flow up rainwater drainage in several areas not predicted by HAZUS No measurements of goodness of fit have been performed: No measurements of goodness of fit have been performed: Too many variables to account for Too many variables to account for Data issues with observed conditions Data issues with observed conditions Photo: Ray Wong Photo: Ray Wong (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods CONCLUSIONS The drawdown of the Glenmore Reservoir in advance of peak inflows is estimated to have:  Reduced total inundation extent by 60 ha  Resulted in 30% fewer dwellings, and 22% fewer residents being directly affected by flooding  Reduced the degree of social impact across all measures used in the study The drawdown of the Glenmore Reservoir in advance of peak inflows is estimated to have:  Reduced total inundation extent by 60 ha  Resulted in 30% fewer dwellings, and 22% fewer residents being directly affected by flooding  Reduced the degree of social impact across all measures used in the study Photo: Ray Wong Photo: Ray Wong (Flickr)

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods Thank you Photo: BBC News

Using HAZUS to Estimate Social Impact Reduction during the June 2013 Alberta Floods REFERENCES Reynolds, R.P., Blakely, D. E. W., & Ryan, S. E. (2014). Potential Reduction of Social Impacts During the June 2013 Alberta Floods as a Result of the Drawdown of the Calgary Glenmore Reservoir. Presented at the Canadian Dam Association Annual Conference, Banff, AB, October Available from Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta Environment and Sustainable Resources Development (AESRD). (2014) Precipitation Map, June , 2013 [Image]. Retrieved from City of Calgary. (2013). Aerial Photograph of Calgary [Image]. Used with permission. Public Safety Canada. (2014). The Canadian Disaster Database on Public Safety Canada website. Retrieved from Reynolds, R.P., Blakely, D. E. W., & Ryan, S. E. (2014). Potential Reduction of Social Impacts During the June 2013 Alberta Floods as a Result of the Drawdown of the Calgary Glenmore Reservoir. Presented at the Canadian Dam Association Annual Conference, Banff, AB, October Available from Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta_Floods_as_a_Result_of_the_Drawdown_of_the_Calgary_Glenmore_Reservoir Alberta Environment and Sustainable Resources Development (AESRD). (2014) Precipitation Map, June , 2013 [Image]. Retrieved from City of Calgary. (2013). Aerial Photograph of Calgary [Image]. Used with permission. Public Safety Canada. (2014). The Canadian Disaster Database on Public Safety Canada website. Retrieved from Photo: Ray Wong Photo: skinnybrager (Flickr)