 An expansion of the Link Light Rail system in the " Sound Transit 2 " package was approved in November 2008 , including 54 % of southwestern Snohomish County voters , funding the extension of light rail to Lynnwood . The 8 @.@ 5 @-@ mile @-@ long ( 13 @.@ 7 km ) light rail line will run along Interstate 5 from Northgate Transit Center in Seattle to Lynnwood Transit Center and is scheduled to begin construction in 2018 and open for service in 2023 . Sound Transit has also begun exploring a possible light rail extension to Everett via Paine Field , anticipated to be included in the " Sound Transit 3 " ballot measure in 2016 . 
