Building a Climate-Resilient City

This briefing by the International Institute for Sustainable Development outlines strategies to enhance the climate resilience of water supply and sanitation systems in Alberta's urban centres, specifically Calgary and Edmonton. It advocates for a transition from highly centralized infrastructure toward a 'multi-barrier' approach incorporating redundancy, decentralization, and low-impact development (LID) to mitigate risks from extreme weather, such as droughts and floods.

• Alberta is projected to experience significant temperature increases if current greenhouse gas emission rates continue, with potential rises of 2.0°C by the 2030s and 4.0°C by the 2060s compared to the 1990s. Precipitation is expected to increase overall, though it will likely decline in the summer and increase in the winter, while climate variability and extreme events like heat waves and heavy rainstorms are expected to increase.
• Calgary and Edmonton lack redundancy in their source water supplies. Edmonton relies entirely on the North Saskatchewan River, which has historically experienced episodes of zero flow. Calgary sources water from the Bow and Elbow watersheds, but these are highly correlated in terms of climatological risk, meaning drought in one typically coincides with drought in the other.
• Building robustness in water systems requires 'multi-barrier' water protection principles to prevent drinking water contamination from source to tap. This includes hardening infrastructure nodes and investing in the ecological integrity of watersheds. For Calgary, specific recommendations include multiply-redundant power systems and advanced fire suppression to mitigate the risk of forest fires in source watersheds, which can decrease water quality through sedimentation and turbidity.
• Decentralized wastewater treatment is presented as a viable alternative to centralized plants to reduce public safety risks during climate shocks. Technologies range from small-footprint secondary treatment replacement reactors serving 50,000 to 1 million people to household-level systems like the Dutch DeSaH concept, which integrates gray water re-use for flushing and black water treatment via fermentation for biogas and fertilizer production.
• Low-impact development (LID) and resourcefulness strategies, such as bio-retention, permeable pavement, and rainwater harvesting, can reduce the load on sewerage systems and mitigate flood risks. The Credit Valley Conservation Authority reported that LID practices reduced annual runoff volumes, phosphorus loadings, and suspended solids by up to 80%, and provided a cooling effect on filtered water of more than 5°C.
• The document recommends several strategic and regulatory actions for cities, including conducting risk management scenario planning for simultaneous flooding and power outages, reviewing the 'First In Time First In Right' (FITFIR) water allocation system during droughts, and exploring water trading systems for industrial consumers to reduce demand.

APA

Venema, H., & Temmer, J. (2017). Building a Climate-Resilient City. International Institute for Sustainable Development. https://www.iisd.org/system/files/publications/pcc-brief-climate-resilient-city-water-supply-sanitation.pdf

Chicago

Venema, Henry, and Jennifer Temmer. Building a Climate-Resilient City. International Institute for Sustainable Development, 2017. https://www.iisd.org/system/files/publications/pcc-brief-climate-resilient-city-water-supply-sanitation.pdf.

Wikipedia

{{cite report |last1=Venema |first1=Henry |last2=Temmer |first2=Jennifer |title=Building a Climate-Resilient City |publisher=International Institute for Sustainable Development |date=2017 |url=https://www.iisd.org/system/files/publications/pcc-brief-climate-resilient-city-water-supply-sanitation.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{venema2017building, author = {Venema, Henry and Temmer, Jennifer}, title = {{Building a Climate-Resilient City}}, institution = {International Institute for Sustainable Development}, year = {2017}, url = {https://www.iisd.org/system/files/publications/pcc-brief-climate-resilient-city-water-supply-sanitation.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }