Dangerous Stretch of SR 18: six fatal accidents, resulting in seven deaths during last 10 months

Between December 13, 2017 and October 12, 2018, there have been six deadly accidents and seven deaths on an approximate 7-mile portion of SR 18, stretching from just east of Issaquah Hobart Road to I-90 near Snoqualmie. Five of those deaths were caused by vehicles or debris crossing the center line in areas where there are no roadway dividers.

This part of SR 18 is notorious with drivers who regularly use it, as it is only a 2 to 3-lane highway with large sections lacking street lights, many portions lacking roadway dividers and it also covers Tiger Mountain with its steep incline/decline and winding roadway.  Once you reach Issaquah Hobart Road, SR 18 becomes a safer, 4-lane highway.

On Friday, October 12th, the Washington State Patrol published a news release saying so far this year there have been 38 deaths on state routes and interstates in King County.

Six of those deaths in 2018 happened on this 7-mile stretch of SR 18. According to WSDOT traffic data, this portion of SR 18 accounted for only a small part – about 2-3%  – of average annual daily traffic volume (AADT) on King County state routes and interstates last year. [Note: only 6 or 7 deaths were included above as one occurred in late 2017]

Over the past decade, as traffic on 405 and 167 has increased, SR 18 has become a common commuter route to the Eastside for southeast King County residents of cities like Maple Valley, Covington, Black Diamond and Kent. It is also a main freight route for commercial trucking between busy Puget Sound ports and the eastern U.S.

As a result, every weekday morning.there are long eastbound SR 18 backups over Tiger Mountain approaching the I-90 interchange. Then in the evening, the westbound backup forces waiting cars into eastbound I-90 traffic – sometimes a mile deep.

Some Help is Coming.

WSDOT will soon begin a $150 million project to redesign the SR 18/I-90 interchange and widen SR 18 from I-90 to near the Raging River. It is expected to be complete in 2023, but there is not enough funding to widen SR 18 all the way to Issaquah Hobart Road. The most recent state budget, though, did provide $1 million for WSDOT study this last remaining expansion of SR 18.

The most recent SR 18 accident – involving a suspected impaired driver that left a mother and daughter dead – left many residents asking why the state can’t take measures to make SR 18 safer until a permanent fix happens.

It’s complicated.

WSDOT stated that it cannot add cement dividers to all parts of SR 18 over Tiger Mountain due to the lack of roadway. It needs an extra six feet to accommodate the two-foot wide barrier and then two feet on each side. To do this would require either widening SR 18 or hardening the shoulders to handle traffic weight in an environmentally sensitive area.

Making SR 18 safer is 25-year Affair for Washington State.

Since 1992 the state has been working to expand SR 18 from a two-lane rural highway to a four-lane controlled access freeway to make it safer. The last widening/lane expansion finished at Issaquah Hobart Road in 2007.  In 2011 the state also improved the SR 18 connection to I-5, changing it from a signal-controlled intersection to a fly over interchange.

The section between Issaquah Hobart to I-90 is the last portion to be improved. 5th District Senator Mark Mullet says it’s a high priority for him. He commented, “My top goal this [legislative] session is to secure funding so we can make SR 18 four lanes all the way to Issaquah Hobart Road.”

The 6 fatal accidents on SR 18 between Issaquah Hobart Road and I-90 include:

  • 12/13/2017: one fatality when debris from truck came loose, caused a driver to cross the center line
  • 2/5/2018: one fatality when a car crossed the center line, hit a semi
  • 5/15/18: one fatality when a car crossed the center line
  • 8/6/18: one fatality due to a wrong-way driver
  • 10/6/18: one fatality due to a driver drifting, hitting cement barrier and flipping into oncoming lanes
  • 10/12/18: two fatalities when a suspected impaired driver crossed the center line

Prior to these most recent fatalities, according to WSDOT accident data, this stretch of SR 18 also had 17 serious collisions involving 55 people between 2010-2017. There were also four fatal collisions between 2010-2016. [Serious collision mean a person involved in the accident sustained a serious, not minor, injury.]


SR 18 accident scene, 2/5/18. Photo: Eastside Fire & Rescue





Comments are closed.


  • First of all, thank you for posting! I lived on the ridge for 11years, and just recently moved to Issaquah. I get mad, because I simply don’t understand why something isn’t done! It also confuses me why this is allowed. I have never lived in an area like this before. I came from California and Phoenix. If there was a problem, it would get fixed. What happens here is the blame game. Nobody wants to pay for anything. Who is ultimately responsible for these deaths?

  • Tina, please feel free to spend some of that CA and AZ money to help fix this. Alternatively, since things are so much better there, you could consider returning to one of those locales. Cheers!

  • Matt, why should CA and AZ pay for this, Washington’s state tax on gas is the second highest in the nation. It charges 49.4 cents per gallon, which is added to the federal gas tax of 18.4 cents and it’s about to double over the next ten years if I-1631 passes.

    1. You misunderstood me. I meant that Tina, instead of pointing fingers at “them” who should “fix things,” might apply some of her own CA/AZ work ethic/funds to try to make a difference. There are actually people who are working on fixing this, you know, and money don’t grow on trees.

    1. You’re right, I am sure Tina, William, and Willy are all working real hard on this, and not just playing the “blame game.” I agree with Megan. Be careful out there and look out for each other.

  • Sounds like the solutions are already known and pretty easy. Prohibit trucks between Issaquah-Hobart and 90, replace the pathetic knee-high barriers with taller ones, and widen the road for a continuous barrier.

    But I guess saving truckers 30 minutes and ensuring some spotted tree frog with a natural lifespan of 6 months and a long term memory of 8 seconds doesn’t have to forage for mosquitos 3 feet further from its hole in the ground is more important than people dying and families being destroyed.

    Probably too expensive to do those things anyway. All the state’s money goes to more important things like suing the federal government for trying to enforce federal laws, giving free needles to every junky in the country who can hitch a ride here, and subsidising college tuition for armies of illegal aliens.

  • Our family just moved to the snoqualmie valley area and travel on 18 whenever we visit family. It is always so nerve wracking. Especially with 2 babies in the car. Call and write to whoever you can to voice your concerns! I recently wrote to wsdot about this specific stretch of road. Also, vote for people who will make this a priority.

    1. To Matt B; the correct term is money doesn’t grow on trees…ignorance leads to bad decisions and bad decisions, such as not attending to one of the most dangerous highways in the state, going on over 20 years, leads to deaths that may have been preventable. It’s our state highway; it’s deadly. It needs to be fixed. Who are these people whom you know that are “working on it”? Please, enlighten us all.

      1. Sure, here ya go. You’re right, it needs to be fixed. Not sure if you were here 20 years ago, but there was no Snoqualmie Ridge then and there wasn’t a problem like there is now. But it’s not like nobody knows and nobody’s doing anything. It takes money. So does education, affordable housing, etc. Kudos to the Tribe for pitching in. Now it is your turn to help out! You could probably donate a million to WSDOT, and you could also call your legislators.




  • Living Snoqualmie