The Bog

The Bog is where thoughts, opinions, discussion pieces, and action converge. Influential thinkers from the water community are invited to share their insights on current or controversial water topics. Please note that the views expressed herein are those of the authors, and do not necessarily reflect the position of the Alberta WaterPortal.

Over the past few months, WaterPortal readers have raised concerns about reduced insurance coverage and increased rates related to flooding. We felt this presented the opportunity to revisit the impacts of flooding on insurance and take a look at broader climate change issues that could impact insurance coverage in the future.  

Conventional stormwater management relies on large-scale facilities such as dry ponds, wet ponds, constructed and natural wetlands to detain flows from large storm events. 

Alberta Lake Management Society was formed in 1991 and works to promote understanding and comprehensive management of lakes and reservoirs and their watersheds.

The following is a summary of the report “Benefit/Cost Analysis of Flood Mitigation Projects for the City of Calgary: Glenmore Reservoir Diversion”. Please read the entire report for a full understanding of the Benefit/Cost Analysis.

The Glenmore Reservoir Diversion, also known as the Calgary Tunnel, will consist of

  • an inlet structure,
  • tunnel, and
  • outlet structure.

The cost benefit analysis assumes the structure would align with Heritage Drive in Calgary and would operate whenever a 1:10 year event or greater would occur.

Glenmore Reservoir Proposed Design Heritage Route

 The Glenmore Reservoir proposed project along the Heritage Drive alignment as drawn by Hatch Mott MacDonald.

The following is a summary of the IBI report “Benefit/Cost Analysis of Flood Mitigation Projects for the City of Calgary: McLean Creek Flood Storage” and the AMEC report “Environmental Overview of the Conceptual Elbow River Dam at McLean Creek”. Please read both reports for a full understanding of the Benefit/Cost Analysis and Environmental Review for this mitigation project. Given the simultaneous release of these reports the McLean Creek Environmental Review has highlighted new items of concern that would require additional costs, and are therefore not reflected in the IBI study.


The McLean Creek Dam will consist of:

  • an earth fill dam built across the main stem of the Elbow River,
  • a combined permanent outlet/spillways structure for discharging normal and flood flows and
  • an auxiliary earth cut channel spillway to protect the dam from extreme floods up to the probable maximum flood event.