The transportation sector accounts for 44 percent of greenhouse gas (GHG) emissions in King County. On-road vehicles such as cars, trucks and buses cause over 26 percent of emissions, while the other 18 percent come from aviation, marine, and off-road mobile equipment. Lowering these emissions will require a combination of reducing car trips overall, using cleaner vehicles, and shifting as many trips as possible from private cars to transit, biking, rolling, and walking. Changes in the transportation sector and shifts in travel behaviors have multiple benefits for the health of all residents and overall quality of life.
Achieving climate gains through transportation and land use actions will mean continuing to advance policies that support safer, healthier, less carbon-intensive, and more efficient modes of transportation, and that encourage and incentivize walkable communities. Ensuring low-carbon modes are less expensive and more convenient to use is key to achieving King County’s climate goals and creating a socially equitable and environmentally sustainable future.
What's at stake
King County has gained over 200,000 residents since 2018 and is expected to have a population of over three million by 2050. Meanwhile, rising housing costs have displaced many low-income households to more affordable but far-reaching parts of the County or region. This means people must travel further, increasing vehicle miles traveled (VMT) and associated emissions to get to work, school, and services. If there are not enough accessible options, it will mean more individual cars on the road, increasing gridlock and emissions.
This makes the transition to a sustainable, equitable transportation system more crucial than ever. King County needs to invest in higher frequency transit service and continue its commitment to transitioning to zero-emission vehicles where and when feasible. By increasing the frequency of bus and rail services and supporting non-motorized travel, King County can make public transit a more viable and attractive option for everyone. This will reduce dependence on private cars and minimize traffic congestion, especially in areas with high population and job density.
A better outcome
King County envisions connected communities that are more compact and walkable, and transit-served neighborhoods for this growing region. These actions will reduce dependence on private cars and minimize traffic congestion, especially in areas with high population and job density. Supporting a shift to zero-emission vehicles will both reduce GHG emissions and significantly improve air quality and public health. Emissions from vehicles, especially heavy-duty trucks, profoundly impact the health of adults and children living near roadways.39 Air pollution from vehicles is linked to increased asthma, respiratory, and cardiovascular health concerns, and disproportionately impacts children, low-income populations and communities of color.40
What we've done to get here
- Implemented Free Youth Transit Pass, launched RapidRide H and G lines, improved connections to Link light rail, expanded flexible transit services such as MetroFlex, and implemented spot improvements for transit speed and reliability.
- Expanded transit-oriented development (TOD) projects, including 232 affordable housing units at Northgate.
- Secured $7.9 million grant from the Washington State Department of Commerce to expand access to electric vehicle (EV) charging throughout the County in fleet, public, and multi-family residential settings.
- Established partnerships with power utilities to pilot curbside EV charging installations and collaborated with adjacent counties to scope the design of a regional EV charging plan.
- Convened Joint Aircraft Emission Technical and Community Task Force to update emissions accounting methodology for aircraft.
39 U.S. Environmental Protection Agency, “Greenhouse Gas Emissions Standards for Heavy-Duty Vehicles: Phase 3 - Regulatory Impact Analysis,” 2024.