One year after a three-day heat wave that killed over 30 people in King County – the most fatalities from a climate-related disaster in the region’s history – experts from public health, climate preparedness, and emergency management are partnering with communities to develop King County’s first-ever Extreme Heat Mitigation Strategy.

King County has applied for a FEMA grant, which has historically not considered extreme heat in hazard mitigation grant programming. The strategy will include both immediate and long-range actions to prepare a region that was primarily designed and built for flood hazards.

"The record heat we experienced late last June – our region's deadliest climate event to date – confirms that the threat is neither speculative nor distant, but certain and immediate. We can, must, and will confront the looming climate crisis with every available resource,” said King County Executive Dow Constantine. “Our team of experts representing public health, climate preparedness, and emergency management will partner with communities to develop a comprehensive strategy to strengthen our response and adapt our built environment to keep people safer while working to dramatically cut carbon emissions countywide."

The Extreme Heat Mitigation Strategy will be an integrated approach that engages and mobilizes county departments, cities, communities, nonprofits, healthcare providers, and emergency responders. It will identify actions needed to enhance the region’s immediate response to extreme heat while adapting the built environment so that people and property are better prepared for more prolonged, hazardous heat waves that climate scientists predict unless there is a dramatic increase in greenhouse gas emissions.

“Last year we experienced the single most deadly climate event in our history, and these events are expected to be longer in duration, and more intense going forward,” said Dr. Jeff Duchin, Health Officer for Public Health – Seattle & King County. “We must prepare both for the inevitable heat events that will continue to challenge us, and also do what we can to minimize the risk for these becoming even more catastrophic in the future.”

Working with communities, experts from the King County Department of Natural Resources, Public Health – Seattle & King County, Office of Emergency Management, and the Climate Equity Community Task Force will develop the strategy.

King County and its partners have improved tactical responses in the wake of last year’s heat wave:

• Created and distributed multi-language materials that inform the public on how to stay safe during heat waves
• Updated public health recommendations for extreme heat to better aligning with National Weather Service heat and health risk factors, which are similar to risk thresholds for air quality but tailored to the health risks of heat
• Increased the number of languages for emergency alerts from two to nine
• Activated the Office of Emergency Management’s Trusted Partner Network of volunteers who help ensure that everyone in King County – regardless of the language they speak – gets the lifesaving public information

King County’s application for the FEMA grant included data from the heat mapping project it conducted in 2020 with the City of Seattle that identified the harmful, inequitable impacts that hotter summers are having on the region. Data analysis shows that areas with hard landscapes held on to heat longer than areas that have more natural landscapes, increasing the potential for heat-related health risks in those areas. More urbanized areas were as much as 20 degrees hotter than less urbanized areas, due in large part to differences in land use and land cover.

Applying data to reduce heat impacts

Heat is evenly distributed during the afternoon

Areas with more natural landscapes retain less heat

The 2021 heat wave included Seattle weather station recordings of 102 degrees on June 26, 104 degrees on June 27, and 108 degrees on June 28. Meanwhile, significantly higher temperatures were recorded farther away from Puget Sound, including 118 degrees in Maple Valley.

“While extreme heat affects everybody, not everybody is affected equally,” said Lara Whitely Binder, King County’s Climate Preparedness Program Manager. “It’s deepening racial inequities, which is why we’re working with members of the Climate Equity Community Task Force to ensure that our strategy creates a more resilient, equitable community that is better prepared for the next extreme heat wave.”

Multiple King County departments are already incorporating heat risk into their operations and initiatives:

• King County Metro Transit is using the data from the heat mapping project to inform bus stop design and amenities to account for more extreme weather events, particularly at stops serving communities disproportionately impacted by climate change. The 3 Million Trees initiative that Executive Constantine kicked off on Earth Day will work with communities where there is the greatest need for urban tree canopy, aligning with King County’s 30-Year Forest Plan.
• King County’s Land Conservation Initiative is already prioritizing the permanent protection of urban greenspace, which provides relief during extreme heat events and prevents an increase in hard landscapes that retain heat.
• King County Parks will use the data to inform park design and improvements to account for hotter temperatures during peak summer months.
• The 2020 Strategic Climate Action Plan includes strategies to make ownership of energy-efficient green homes – which cost less to heat and cool – more equitable.
• King County is updating land-use and urban planning policies to prioritize greenspace and other cooling strategies, including providing more equitable access to energy-efficient green homes that are designed to stay cooler during increasingly hot summers.

The Extreme Heat Mitigation Strategy is part of King County’s 2020 Strategic Climate Action Plan and its 2020 King County Regional Hazard Mitigation Plan.

“Extreme heat is one of King County’s severe weather hazards. We anticipate this happening more often and we encourage everyone to develop an emergency plan to help prepare for and be resilient to this hazard – what are you going to do, where are you going to go, and what supplies do you need before the extreme heat occurs?” said Brendan McCluskey, Director of the King County Office of Emergency Management. “We also encourage people to stay informed during the extreme heat events, and a good way to do that is to sign up for ALERT King County at kingcounty.gov/alert.” 

Extreme heat’s impact on frontline communities

Recognizing that climate change-related incidents don’t affect everyone equally, King County convened as part of its Strategic Climate Action Plan update in 2019 the Climate Equity Community Task Force to bring multi-ethnic and multi-racial cross-sector experiences and voices into climate-related discussions.

The task force served as the primary body for identifying community-driven climate actions for the plan update, working with the support of an internal advisory team of staff from across a wide range of King County departments.

Task force members developed climate actions and priorities that recognize the connections between climate change and other social issues such as housing, food access, and community health. The climate justice section includes actions focused on building frontline community capacity, mitigating environmental injustice, and ensuring equitable distribution of environmental benefits.