Image credit: Bri via Wikimedia Commons. License: CC BY 4.0.
Northbound Interstate 405 is closing through a key Kirkland segment for the entire weekend, and Washington transportation officials are warning travelers to expect miles-long backups. The full closure begins at 11 p.m. Friday, August 28, and is scheduled to end at 4 a.m. Monday, August 31.
The most important planning move is to avoid treating this like an ordinary lane reduction. All northbound lanes will close between Northeast 70th Place and Northeast 85th Street, with additional lane and ramp restrictions north of the closure. WSDOT says traffic effects can spread to nearby highways and local streets at unfamiliar times.
- Closure: Northbound I-405 from Northeast 70th Place to Northeast 85th Street.
- Timing: 11 p.m. Friday, August 28, to 4 a.m. Monday, August 31.
- Extra restrictions: Up to three lanes close north to Northeast 100th Street.
- Main risk: Miles-long backups and heavier traffic on local streets.
- Best move: Use transit, leave early, and check live traffic before departure.
Exactly where northbound I-405 closes
The Washington State Department of Transportation notice closes every northbound lane from Northeast 70th Place to Northeast 85th Street. The Northeast 70th Place on-ramp to northbound I-405 and the northbound off-ramp to Northeast 85th Street also close.
North of the full closure, up to three northbound lanes will be closed from the Northeast 85th Street on-ramp to Northeast 100th Street. WSDOT says the Northeast 85th Street on-ramp to northbound I-405 will remain open, and a signed detour will guide drivers around the blocked segment.
The closure spans only part of the Eastside freeway on a map, but the traffic effect is larger than the closed mileage. Northbound drivers approaching from Bellevue and Renton have to leave a major regional route before the closure, while local Kirkland drivers and detouring traffic compete for the same surface streets.
The City of Kirkland’s project update also lists the August 28 to 31 northbound closure from Northeast 70th Place. It advises residents to use WSDOT’s current project information for the latest ramp and lane status.
Why this weekend could be unusually slow
WSDOT does not limit its warning to the closed freeway. The agency says drivers should expect miles-long backups on northbound I-405, heavier traffic on nearby highways and local streets, and longer trips that may be less predictable than usual. It specifically warns that delays may appear in new places and at new times as travelers alter their routes.
Independent construction reporting from the Seattle Daily Journal of Commerce identifies the work as part of the $234.4 million I-405/Northeast 85th Street Interchange and Inline Bus Rapid Transit Station Project. That report says crews are installing a concrete culvert to reconnect a fish passage under northbound I-405 with the section built under the southbound freeway during a July closure.
There is another regional constraint to keep in mind. WSDOT says northbound Interstate 5 in Seattle is reduced to two lanes across the Ship Canal Bridge through the end of 2026, with the express lanes operating northbound around the clock. That means a driver who abandons I-405 for a route through central Seattle may still encounter a second construction bottleneck.
Put those pieces together and the danger becomes clear: navigation apps may send many drivers toward the same apparent alternative, then recalculate again as local congestion builds. The fastest route at breakfast may not remain fastest after lunch, and a familiar shortcut may carry more traffic than it normally sees.
| If your trip involves… | Best next step |
|---|---|
| Driving north through Kirkland | Reroute before reaching Northeast 70th Place and add a large time buffer. |
| A fixed airport departure | Leave early enough for detour and terminal time, or use transit where practical. |
| A flexible Eastside outing | Move it outside the closure window or choose a closer destination. |
| Downtown Kirkland access | Expect local streets to carry diverted freeway traffic. |
| A Monday morning trip | Verify the 4 a.m. reopening before relying on normal routing. |
Airport, cruise, and weekend-trip decisions
Travelers heading from the Eastside toward Seattle-Tacoma International Airport should not assume a normal weekend drive. The closure itself is northbound, but diversion traffic can affect connecting roads and create delays in more than one direction. Check the WSDOT Travel Center map before committing to a route, then check again shortly before departure.
A northbound traveler returning from the airport toward Kirkland, Woodinville, Bothell, or communities farther north has the most direct exposure. If the journey connects with a flight, cruise, train, or ticketed event, build the buffer around the appointment you cannot move. Saving ten minutes on a detour is not useful if the route has no recovery time for a sudden traffic spike.
Seattle cruise travelers can review Deep Arrival’s Seattle cruise port to airport guide for the terminal-to-airport part of the transfer. This I-405 closure is a separate Eastside constraint, so add it only when your hotel, home, rental-car route, or pickup crosses the affected corridor.
Visitors planning a Pike Place Market stop should also avoid turning a flexible meal into a fixed-time dash across the region. Deep Arrival’s Pike Place Market planner can help organize the stop, but the traffic decision still belongs in the live map on this particular weekend.
What the construction crew is doing
WSDOT says crews will excavate a section of the freeway to install a concrete culvert. The goal is to reconnect fish passage beneath the northbound lanes with a section under the southbound lanes that was installed during a full closure in July.
The work belongs to a larger interchange rebuild at Northeast 85th Street. WSDOT, Sound Transit, the City of Kirkland, and contractor Graham Contracting are creating a new interchange configuration and an inline bus rapid transit station that will connect with Sound Transit’s future Stride service. The design also creates direct access to the I-405 express toll lanes.
That scope explains why a full freeway closure is necessary rather than a nighttime shoulder closure. Crews are not only repainting lanes. They need access beneath the roadway, space for heavy equipment, and a continuous work window before traffic returns Monday morning.
WSDOT notes that the schedule depends on suitable weather and may be changed if rain interferes. That is why the Monday reopening should be checked rather than assumed. A rescheduled closure would also create a new traveler decision for a later weekend.
How to reduce the disruption
Start with time, not a favorite alternate route. WSDOT recommends transit and park-and-ride options, flexible departure times, and real-time traffic information. Those choices spread demand and give travelers a better chance of adjusting before they join a queue.
If driving is unavoidable, enter the trip only after everyone and everything is ready. Fuel the vehicle, load luggage, and settle the pickup plan before the closure approach. A small delay at home is easier to absorb than a last-minute stop after traffic has already committed you to a detour.
Do not follow an unofficial shortcut through a closed street, work zone, or residential block. Follow the signed detour and live road restrictions. Navigation apps can suggest a legal alternate, but temporary signs and traffic-control workers take priority when conditions differ from the map.
Drivers should also slow down near the work limits. WSDOT’s safety guidance asks travelers to follow posted speeds, keep phones down, and stay calm. Congestion is frustrating, but risky lane changes do not reopen a closed freeway and can turn a planned construction delay into an unplanned crash delay.
Treat the Kirkland closure as a regional disruption from Friday night through early Monday, not a small interchange repair. Northbound trips through the Eastside need a detour and a larger-than-normal buffer. Airport, cruise, and ticketed-event travelers should protect the fixed departure first, then choose the route.
What to watch through Monday
Watch WSDOT’s Travel Center map and mobile app for the live closure status, incident overlays, and any weather-related schedule change. The official news release supplies the planned limits, but the live map is the better source for conditions once drivers begin moving.
Watch local streets around Northeast 70th Place, Northeast 85th Street, and central Kirkland. A route that avoids the freeway closure can still become slow when many other drivers make the same choice. If a trip is optional, moving it by a few hours may produce a bigger benefit than changing roads.
Finally, verify the reopening before an early Monday trip. The scheduled end is 4 a.m. August 31. Until WSDOT shows the roadway open, do not build a tight airport or work schedule around the assumption that every lane will return exactly on time.
When does northbound I-405 close in Kirkland?
The planned closure runs from 11 p.m. Friday, August 28, to 4 a.m. Monday, August 31, 2026.
Which part of I-405 is fully closed?
All northbound lanes close from Northeast 70th Place to Northeast 85th Street.
Which ramps close?
The Northeast 70th Place on-ramp to northbound I-405 and the northbound off-ramp to Northeast 85th Street close.
Will the Northeast 85th Street northbound on-ramp stay open?
Yes, WSDOT says it remains open, though up to three lanes north of that ramp also close to Northeast 100th Street.
Why is WSDOT closing the freeway?
Crews need to excavate the roadway and install a concrete culvert that reconnects fish passage under the northbound and southbound lanes.
