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Vision Zero | We’re accelerating Leading Pedestrian Interval (LPI) signal rollout throughout the city

People crossing the street at 5th and Marion, where there is a leading pedestrian interval in place. Photo: SDOT


  • We’re expanding Leading Pedestrian Interval (LPI) signals at 100 locations this year as part of our momentum building actions from the Vision Zero top-to-bottom review, accelerating their rollout at locations where existing signal boxes allow. 
  • LPI signals are a proven method to improve safety of people walking, rolling, and biking at intersections by giving them a three-to-seven second head start to cross the street, increasing their visibility. 
  • At locations where LPIs were installed from 2009-2018, we’ve seen a 48% reduction in turning collisions involving pedestrians, and a 34% reduction in serious injury and fatal pedestrian collisions.

Failure to yield to pedestrians is one of the leading causes of crashes in Seattle. At traffic signals, incidents involving vehicle drivers turning account for 35 percent of all pedestrian-involved crashes citywide.

Earlier this year, we published a top-to bottom review of our Vision Zero initiative, which aims to end traffic related deaths and serious injuries on city streets by 2030. This review was commissioned by Mayor Bruce Harrell and SDOT Director Greg Spotts to evaluate our processes after seeing fatal and serious injury crashes increase in recent years.  

One of the momentum-building actions to come out of the review is to accelerate planning for citywide implementation of Leading Pedestrian Interval (LPI) signals, a treatment to give pedestrians a head start to reduce collisions. We are on track to install LPIs at 100 locations in 2023, with 49 already installed. We are also developing a strategy for implementation across the city over the next few years. 

We’ve installed LPIs at over 50 percent of our signalized intersections. It turns on the walk signal three to seven seconds before people driving get the green light. Doing so offers people walking a lead, prioritizing them, and making them more visible to drivers.

When it comes to identifying where we’ll put new LPIs, we focus primarily on our high-injury streets. By prioritizing areas where we already see incidents, we can increase overall safety before turning to locations that have less frequent or less severe conflicts.