Lane reduction on State Route 18 (Cameron Sires/)

Data shows more collisions in SR 18 construction zone

75% increase in collisions in 2023.

As the construction between State Route 18 and Interstate 90 continues, Eastside Fire & Rescue has collected data on motor vehicle collisions occurring specifically between construction zones from State Route 18 heading toward the interchange.

The data showed nearly a 75% increase in collisions in 2023 compared to 2022.

The I-90/SR 18 Interchange Improvements are a response to the highway interchange becoming one of the busiest in the state, causing backups during peak times and weekends, according to the Washington State Department of Transportation (WSDOT)

The area had a notable number of collision rates before the beginning of construction, said Catherine Breault, spokesperson for the Eastside Fire & Rescue.

In addressing these concerns, the project plans include building a diverging diamond on the interchange — improving traffic flow and safety for residents navigating through this corridor, according to WSDOT.

The construction continues south alongside SR 18 to widen the highway into two lanes between the interchange and Deep Creek, which involves the construction of three new bridges across Lake Creek, Raging River and Deep Creek.

The project, initiated in April 2023, witnessed a notable increase in collisions, particularly during August 2023, as reported by Eastside Fire & Rescue, which responded to these collisions.

Fire Chief Ben Lane explained in an email that the sharp increase in collisions began in August 2023, aligning with the implementation of the traffic lane reduction. Lane reductions span from the interchange, down State Route 18 and slightly past the Raging River bridge.

“A comparison of the same stretch of roadway from the year before construction to the present highlights a substantial 75% increase in collisions,” he wrote.

The Eastside Fire & Rescue data documents collisions exclusively between the interchange and the Raging River bridge.

According to the data, the agency responded to eight collisions in this zone in 2022 before construction began. In 2023, the team responded to 12 collision incidents, with four collisions reported in August 2023 — the highest number of collisions in any single month during either 2022 or 2023.

Breault noted the statistics provided were solely on the number of Eastside Fire & Rescue responses to collisions.

“This is just incidents that we’ve responded to with at least one apparatus,” she said. “So, the [Washington State Patrol] might even have different numbers or more numbers if there wasn’t an injury involved or a need for an aid car.”

The Washington State Patrol (WSP) did report a significantly greater number of collisions in the same area Eastside Fire & Rescue reported; however, the numbers told a similar story.

In 2022, there were 48 reported collisions between Raging River and the Interchange — where the lane reduction would take place the following year. Between August and December 2023, 21 of those collisions occurred, according to the WSP collision analysis tool.

In 2023, there were 64 reported collisions along the same stretch of road. Out of these collisions, 41 of them occurred between August — when lane reductions began— and December.

Currently, in 2024, three collisions have taken place in this stretch of SR 18. Two out of the three were located near the Raging River bridge.

Although there is an estimated 33% increase in collisions from 2022 to 2023, Breault emphasized the crucial need to continue the project along SR 18.

“What we want to highlight, or you know, just kind of reiterate, is that the project is really of most importance because obviously we had collisions in the area before, and we want the construction to stay on time,” she said. “The longer that timeline goes out, the more risk you have in that area.”

Even though many commuters use this stretch of SR 18, Breault cautioned, those drivers still need to slow down and take caution within those stretches.

“That obviously can slow down traffic, but we want that to be our priority, for our drivers to pay attention and slow down in those construction zones because they are dangerous, especially when we’re changing the way we drive every day.”

WSDOT spokesperson Marcus Humberg attributed the rapid change in road conditions near Tiger Mountain and SR 18 as a factor in increased accidents.

“We already have seen heavy snow and ice affecting travel across all our mountain passes, causing spinouts and collisions, which lead to extended closures of the highway,” he said.

Although delays due to weather and availability of materials could have an effect on when the road fully opens, Humberg said they are optimistic about the current schedule.

“The current schedule from our contractor, Aecon, shows us putting traffic on the newly completed lanes and bridges by spring 2025, with some additional in-stream work at Deep Creek finishing later in fall 2025, which should have only minimal effects to travel in the area,” he said.

WSDOT echoed that drivers should give themselves extra time to navigate construction and be patient.

“This is for the safety of our workers and everyone who is on the road. We want everyone to be able to go home at the end of the day and reach their destinations safely,” Humberg said.

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Lane reduction on State Route 18 (Cameron Sires/)

Lane reduction on State Route 18 (Cameron Sires/)

Screenshot from the Washington State Patrol
This map depicts the collisions that occurred throughout 2023 along the State Route 18. The darker the dot means there are multiple collisions at that location.

Screenshot from the Washington State Patrol This map depicts the collisions that occurred throughout 2023 along the State Route 18. The darker the dot means there are multiple collisions at that location.

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