The annual Seafair festival begins when the pirates land the first week of July and ends with the Patriots Jet Team flying over Lake Washington in a spectacular display of aeronautics. The Washington State Department of Transportation's (WSDOT) role is to make sure drivers and pilots are safe during the annual event.
The Federal Aviation Administration requires WSDOT to close Interstate 90 while the Patriots Jet Team perform for the safety of both drivers and pilots.
Which roads and ramps will be closed?
Interstate 90 will be closed to all vehicles, pedestrians and cyclists, eastbound and westbound, mainline and express lanes, between Interstate 5 in Seattle to Island Crest Way on Mercer Island:
- Friday, Aug. 2: 1:15 p.m. - 2:40 p.m., (Practice)
- Saturday, Aug. 3: 1:15 p.m. - 2:40 p.m., (Full show)
- Sunday, Aug. 4: 1:15 p.m. - 2:40 p.m., (Full show)
* The bridge highrises will still be accessible to pedestrians and cyclists. However, no one on foot or bike can travel beyond the highrises up to 30 minutes prior to posted closure times.
*I-90 east of Mercer Island will NOT be closed during the performance, although drivers should note that heavy congestion during these closures often restricts access to the exits.
The I-90 express lanes will close at 12:30 p.m. Friday, Saturday, and Sunday. The lanes will reopen to eastbound traffic by 3 p.m. each day.
Which ramps will be closed?
- Northbound I-5 to eastbound I-90 ramp (closed up to 30 minutes prior to show or practice)
- Southbound I-5 to eastbound I-90 ramp (closed up to 30 minutes prior to show or practice)
- Southbound and northbound Rainier Avenue ramps (closed up to 30 minutes prior to show or practice)
- 76th Avenue to westbound I-90 (closed up to 30 minutes prior to show or practice)
- Island Crest Way to westbound I-90 (closed up to 30 minutes prior to show or practice)
- Eastbound I-90 to West Mercer Way (closed up to 30 minutes prior to show or practice)
- East Mercer Way to westbound I-90 (closed up one hour prior to show or practice)
- West Mercer Way to westbound I-90 (up to one hour prior to show or practice)
What specific regulation forces the closure of I-90?
Horizontal and vertical restrictions are in place to protect motorists from planes, jets, and other aircraft. Teams like the Patriots Jet Team, Blue Angles and the Thunderbirds routinely violate these restrictions. To perform, they must acquire a special waiver. This waiver carries safety stipulations. These stipulations require a large three-dimensional aerobatic box to protect people and property. This rule establishes a so-called “clear zone” that WSDOT must respect. As a result, we must close I-90 during the annual SEAFAIR airshow performances. Additionally, keeping drivers off the bridge while the Patriots Jet Team are in the air keeps drivers from being distracted and prevents collisions on the bridge.
Why does the bridge close before the Patriots Jet Team actually perform?
Before each performance the Patriots Jet Team will be in the air, but will not perform specific maneuvers. The bridge closes because it still poses a safety concern.
How will I know when the road is actually closed?
WSDOT will use variable message signs on I-5 and I-90 to countdown to the closures. We will also use social media such as Twitter to alert travelers. We strongly advise motorists to plan alternate routes in advance. Please do not expect to cross the bridge at the last minute. Congestion and unexpected delays on the roadway may leave you in your car sitting in traffic waiting out the performance.
Will the SR 520 bridge be affected?
The SR 520 bridge will remain open to vehicle traffic and tolls will be collected according to the rate schedule. Drivers crossing SR 520 should expect heavy traffic, significant delays and plan for additional time to cross the lake.
Will the SR 520 bridge drawspan be opened for boats when the Patriots Jet Team is flying?
No, the bridge drawspan will not open for any vessel during these times:
- Friday, Aug. 2 - 12:30 - 7 p.m.
- Saturday, Aug. 3 and Sunday, Aug. 4 - 12:30 - 3:30 p.m.
Who will keep people and vehicles off the roadway during the performance?
WSDOT works with Washington State Patrol to control on-ramps and
off-ramps and keep pedestrians off I-90. The Washington State Patrol will open the roadway as soon as safely possible after the Patriots performances are finished.
WSDOT’s Incident Response Teams will also patrol SR 520, I-405 and
I-5 to keep these alternate routes free of disabled vehicles so traffic will move as freely as possible.
I live on Mercer Island, how will I be affected?
Drivers who need to get around Mercer Island should follow signs for detour routes. Most roads will be open for local access only.
What if I have a medical emergency and I need to get to Harborview Medical Center or Children’s Hospital?
The center roadway of I-90 is reserved for this purpose. Contact 911 and Washington State Patrol will escort you to the hospital.
Where can I get more information?