#GoodbyeViaduct and hello, SR #99Tunnel!
The new SR 99 tunnel will provide direct access between the stadiums and the Space Needle. Running two miles long, it will be the largest double-deck highway tunnel of its kind in the country. Pretty cool, right? The tunnel offers new options for driving to and through downtown Seattle, which will alter traffic patterns and change how we get around downtown. But, Seattle, don’t freak out – here’s what you need to know as you prepare for your new commute.
☝️ Coming into Seattle from the SOUTH☝️
The tunnel’s south portal is just west of CenturyLink Field in SODO. On- and off-ramps in both directions will connect SR 99 to the stadiums, Alaskan Way and Colman Dock along the waterfront, and downtown Seattle. Just to the east is the start of I-90 and connections to I-5.
Coming northbound on SR 99, the exit to downtown and Alaskan Way will be the last exit before the tunnel. That ramp will end at a new intersection of South Dearborn Street and Alaskan Way South (shown below). Drivers heading to southbound SR 99 from downtown or the stadiums will use Alaskan Way or First Avenue South to reach the new southbound on-ramp at this same intersection.
👇Coming into Seattle from the NORTH👇
The tunnel’s north portal sits just east of Seattle Center, near the Space Needle. On- and off-ramps will provide connections to nearby Denny Way, Dexter Avenue and Mercer Street, as well as routes to reach I-5.
Southbound drivers can take the off-ramp to Denny Way and downtown, which ends at the intersection of Aurora Avenue North and Harrison Street. From there they can head to Seattle Center (west), South Lake Union (east), or into downtown (south).
Drivers seeking to head north on SR 99 will use Aurora Avenue North or Harrison Street to reach the northbound on-ramp.
Three blocks of Aurora Avenue North, between Harrison Street and Denny Way, will be reconnected as part of the North Surface Streets project (see below). The approach to the Battery Street Tunnel will be brought up to grade and rebuilt, and John and Thomas streets will be reconnected east-west across Aurora Avenue North. Learn more about this work on WSDOT’s website.
👉Getting in the new tunnel from DOWNTOWN:👈
If you’re in downtown Seattle and trying to get onto SR 99, check out these videos from WSDOT:
Inside the Tunnel:
The tunnel features two lanes in each direction. Unlike the Alaskan Way Viaduct’s extremely narrow shoulders, the tunnel has an eight-foot shoulder in each direction for vehicles to pull over in case of breakdown or crashes. Long, gentle curves will allow for safe sight distances.
The tunnel is built to modern earthquake standards and features smart systems that work together to keep traffic moving safely. In the event of an emergency, exits every 650 feet provide shelter and escape routes, while a state-of-the-art ventilation system assists first responders and fights fire and fumes.