Central Puget Sound Interstate 90 - Dashboard
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Performance indicators for the I-90 corridor in the central Puget Sound region
Indicators
This dashboard shows three multimodal performance indicators for Interstate 90 in the central Puget Sound region: annual general purpose (GP) lane person miles traveled, annual GP vehicle delay, percentage of park and ride spaces occupied. For details on the methodology used to calculate person miles traveled and vehicle delay, refer to WSDOT's Handbook for Corridor Capacity Evaluation (PDF 5.9MB).
Sources: WSDOT Transportation Safety and Systems Analysis Division and WSDOT TRACFLOW (https://tracflow.wsdot.wa.gov/)
Note: Park & Rides utilization rates data will no longer available from 2020.
Multi-year trends
In 2021, annual GP person miles traveled and vehicle delay increased from 2020, due to the recovery of traffic volume. In 2020, due to the statewide response to COVID-19—which sought to limit travel to essential trips—annual GP person miles traveled decreased considerably in 2020 and there was no delay. From 2017 through 2019, the central Puget Sound region experienced substantial economic growth and increases in employment, which resulted in more commuters. During this time, rapidly increasing housing prices caused many Washingtonians in this region to move further from their workplaces to find housing they could afford; many of these people commute on I-90. Annual GP person miles traveled increased between 2017 and 2019. Annual GP vehicle delay decreased over the same period, likely due at least in part to the June 2017 opening of the HOV lanes between Seattle and Bellevue.
Traffic on the I-90 corridor is heavily influenced by congestion on the major north/south routes: I-5 and I-405. When these routes are congested, traffic backs up onto I-90, resulting in delays.
Annual highlights
In 2021, annual GP person miles traveled and vehicle delay increased from 2020, due to recovery of traffic volume. Nearly 413 million person miles were traveled in the GP lanes on I-90 between Seattle and Bellevue, up 10% from 377 million in 2020. Travelers on this corridor experienced 11 thousand hours of vehicle delay in 2021, up from 0 in 2020
In 2020, the statewide response to COVID-19 resulted in a significant reduction in GP person miles traveled and annual delay. Nearly 377 million person miles were traveled in the GP lanes on I-90 between Seattle and Bellevue, down over 26% from 512 million in 2019. Travelers on this corridor experienced no vehicle delay in 2020, down from 222,000 in 2019.
In 2019, about 512 million person miles were traveled in the GP lanes on I-90 between Seattle and Bellevue, up 1% from 506 million in 2018. Travelers on this corridor experienced 222,000 hours of vehicle delay in 2019, down 17% from 222,000 in 2018. Approximately 86% of available parking spaces at Park & Ride lots on this corridor were occupied in 2019, up from 82% in 2018.
In 2018, approximately 506 million person miles were traveled in the GP lanes on I-90 between Seattle and Bellevue, up 1% from 501 million in 2017. Travelers on this corridor experienced 266,000 hours of vehicle delay in 2018, up 15% from 231,000 in 2017. Approximately 82% of available parking spaces at Park & Ride lots on this corridor were occupied in 2018, down from 99% in 2017.
In 2017, over 501 million person miles were traveled in the GP lanes on I-90 between Seattle and Bellevue, down 2% from 511 million in 2016. Travelers on this corridor experienced 231,000 hours of vehicle delay in 2017, down 38% from 373,000 in 2016. Over 99% of parking spaces at Park & Ride lots on this corridor were occupied in 2017, the same as in 2016.
WSDOT opened new HOV lanes on I-90 between Seattle and Bellevue on June 1, 2017, after the agency closed the existing I-90 express lanes to make room for Sound Transit's light rail East Link Extension project. Unlike the express lanes, the HOV lanes are open in both directions 24 hours a day, and appear to have significantly improved travel time reliability for HOV lane users (people traveling by carpool, vanpool, or transit). Given the 38% drop in delay in the I-90 GP lanes between 2016 and 2017, the new HOV lanes appear to have also significantly relieved GP lane congestion during their first six months of operation.