King County Solid Waste Climate Vulnerability Assessment

King County Solid Waste Division (SWD) partnered with Herrera to complete its first-ever climate vulnerability assessment — a critical step toward ensuring reliable, resilient solid waste operations in a changing climate. Herrera led the project, guiding SWD through a comprehensive process to identify critical systems, assess exposure and vulnerability, and develop actionable adaptation strategies.

The assessment examined how climate hazards such as extreme heat, intense rainfall, flooding, and wildfire could impact daily operations, worker safety, and infrastructure across landfills and transfer stations. Through interviews, site visits, spatial analysis, and collaborative workshops, the team identified systems and operations most at risk — particularly those related to water management, including stormwater, leachate, and landfill gas systems designed for a climate that no longer reflects today’s realities.

Key outcomes included:

• A clear evaluation of climate risks to SWD facilities and operations.
• Development of 18 adaptation strategies focused on the most vulnerable systems, with specific actions to reduce exposure and risk.
• Additional refinement of 4 adaptation strategies that were priorities for advancement through King County’s updated Strategic Climate Action Plan, moving from planning to implementation.

By identifying vulnerabilities early and creating practical, on-the-ground solutions, this project helps King County prepare its solid waste systems for an unpredictable future that may include hotter, drier summers and wetter winters.