Spokane's Heat Islands: A Deadly Post-War Legacy

Post-World War II urban development in Spokane, like many U.S. cities, focused heavily on automobile infrastructure and modernization. This led to vast expanses of impervious surfaces and a lack of green spaces, contributing significantly to the urban heat island effect. This phenomenon, where metropolitan areas with dense concrete trap heat, disproportionately impacts lower-income residents during heat waves.

The lethal heat wave of June 2021, which saw temperatures reach 109 degrees Fahrenheit in Spokane, resulted in 19 deaths in Spokane County and over 300 hospitalizations. This event highlighted the vulnerability of the city to extreme heat. In response, Gonzaga University began tracking urban heat islands, initially focusing on support for the homeless but discovering that most heat-related fatalities occurred among housed individuals.

Efforts to bolster climate resilience in Spokane have faced setbacks. A significant $19.9 million grant from the EPA, intended for resilience hubs and low-income housing upgrades, was rescinded in May 2025. While a federal judge ruled this termination unlawful, no relief was provided. However, a $6 million federal grant for a tree equity program was reinstated, aimed at increasing tree canopy to mitigate urban heat islands.

Spokane's electrical grid also experienced strain during the 2021 heat dome, leading to power outages due to high air conditioner usage. Utility provider Avista has since made investments to strengthen the system. Experts suggest practical solutions like painting dark surfaces white for an albedo effect, while also emphasizing the need for infrastructure that accounts for future climate conditions, such as incorporating sea-level rise and increased rainfall in designs.