• Project

SR 18 - Issaquah/Hobart Rd to Deep Creek - Widening

Project overview

SR 18 is a crucial highway connecting the south Puget Sound area with I-90, the state's main east-west route. SR 18 has experienced frequent congestion and collisions for decades.

We are receiving construction funding from the 2022 Move Ahead Washington transportation package and preparing to widen a 5-mile section of SR 18 between Issaquah-Hobart Road and Deep Creek.

2019 - late 2020s
Project status
$665 million

What to expect

We anticipate it will take several construction seasons to complete the work because we will keep the highway open during construction. The project is being readied for construction, which could begin as early as 2025 and last until 2029.


WSDOT is proposing to widen five miles of SR 18 to two lanes in each direction between Issaquah/Hobart Road and Deep Creek.