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“We’ll work the best we can with Mother Nature to keep the folks safe.”

The report found that any efforts to protect the town are constrained by its unfortunate location in an alluvial fan of the Highwood river where the waterway was naturally prone to choking on its own sediment and changing course despite efforts to train its flows through the construction of berms and dykes.

While the floods two years ago caused an estimated $94 million in damages to the town, the study found that the estimated average annual loss from flooding is less than $1 million.

“This would economically justify implementing mitigating measures to an amount of only $25 million or in exceptional cases a maximum of $40 million,” the report said.

“Taking no flood mitigation measures and accepting the damages is to be preferred.”

The Dutch consultants were also sharply critical of Alberta-based engineers with AECOM and Worley Parsons who used the 2013 event as the “flood to conquer” without doing a social cost-benefit analysis to justify the large expenditures on mitigation projects like the diversion canal around the southern edge of the town.

“We find it hard to imagine that the benefits to society would justify the huge costs,” the report said.

“This measure, moreover, transfers the risk to the valley of the Little Bow River, where the downstream consequences may well be larger.”

Raising the height of the highway bridge through the centre of town so it doesn’t obstruct flow during a flood and removing dykes around properties purchased through the government’s relocation program to allow more room for the river may prove cheap and effective, the report said.

Getting homes and businesses well away from a river that is inherently vulnerable to overtopping its banks and meandering would be prudent.

“It is recommended to not develop (build) in the floodway and flood fringe,” the report said.

“Detailed flood hazard mapping may inform such a spatial planning policy.”

Neither High River mayor Craig Snodgrass nor local MLA Danielle Smith could be reached for comment.

mmcclure@calgaryherald.com

Twitter.com/mattmcclure2