What is Old is New Again: Elbow River Historical Detention and Diversion Sites Report

A new report on historically identified detention and diversion sites, commissioned by the Alberta Flood Recovery Task Force and executed by Alberta WaterSMART, has been added to the Flood Recovery Task Force page.

This report explores 100-110 years of historical documentation on previously considered options for both drought and flood mitigation in the Elbow River Watershed. Many of the potential options come from reports by the Department of the Interior (established in 1873 by Sir John A. MacDonald) which had surveyed the land by foot looking for sites where the topography of Alberta could be used to create reservoirs to combat drought. 

Executive Summary

The purpose of this study is to review historical records to identify previously proposed detention and diversion sites on the Elbow River, and determine if these historical sites have any merit for further investigation and consideration by the Government of Alberta (GoA) as an alternative to the mitigation options currently being reviewed by the Flood Recovery Task Force.

An initial historical review of potential detention and diversion sites on the Elbow River provided twelve possible options that could be implemented to mitigate for both flood and drought.

Of the twelve identified historical detention and diversion sites it is recommended that the Priddis Creek diversion be seriously considered as an option for flood and drought mitigation. The Priddis Creek diversion is designed to mitigate for flooding upstream of Bragg Creek and the City of Calgary using the natural creek bed and low lying topographical areas for channeling the water flows. By using natural topography the Priddis Creek diversion has a greater potential to slow down the water; subsequently reducing peak flows. It is also recommended that the historical resevoir sites identifed by the Department of Interior in the 1890s, along with the McLean Site, should be further investigated for feasibility. These storage sites are recommended due to their use of natural topography and their ability to mitigate for flooding upstream of Bragg Creek and the City of Calgary.

In order to ensure that all the flood mitigation options are considered for all watersheds throughout Alberta, Alberta WaterSMART recommends further investigation into all mitigation options by continuing to undertake this type of historical analysis for all watersheds throughout Alberta.

Some of the current proposed options have received criticism by the water community for the potential impact they would have on the watershed. Do any of these proposed options seem like promising alternatives?  If not, what options would you recommend exploring?