Infrastructure

I-405 and SR 9 closures begin overnight

Saturday, August 29, 2026

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I-405 will see multiple overnight closures starting Friday, Aug. 28. Southbound lanes from milepost 14. 25 to 12. 5 will close from 10 p.m. to 8 a.m. Saturday, and northbound lanes from Northeast 85th Street to 100th Street will close from 11 p.m. Friday to 5 a.m. Monday, Aug. 31.

State Route 9 will have single-lane traffic near Kalloch Road (MP 59) with alternating signals for 42 days until Sept. 14 for fish passage construction. A separate section near Mount Vernon Big Lake Road (MP 49) will alternate traffic weekdays from 10 a.m. to 4 p.m. through Sept. 3.

WSDOT states the projects aim to improve infrastructure, with details available on their project webpage. Drivers should expect delays and use detours where provided.

📄 Source: WSDOT — Highway Construction & Closures — https://wsdot.wa.gov/travel/road-construction

Source receipts6 of 11 claims supported · 55%

Legacy automated check: the original source text was not preserved. These earlier verdicts have not passed the current publication checks and may contain errors. Source: original document ↗

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I-405 will see multiple overnight closures starting Friday, Aug. 28.“405: Up to four lanes of southbound I-405 from milepost 14.25 to milepost 12.5 will be closed overnight, 10 p.m. Friday, Aug. 28 – 8 a.m. Saturday, Aug. 29.”
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Southbound lanes from milepost 14. 25 to 12. 5 will close from 10 p.m. to 8 a.m. SaturdayNo usable supporting receipt — unverified.
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The closure is on Saturday, Aug. 28.No usable supporting receipt — unverified.
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Northbound lanes from Northeast 85th Street to 100th Street will close from 11 p.m. Friday to 5 a.m. Monday, Aug. 31.“405: Up to three lanes of northbound I-405 will close from the Northeast 85th Street on-ramp to Northeast 100th Street from 11 p.m. Friday Aug. 28 to 5 a.m. Monday, Aug. 31. A signed detour will be in place.”
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The closure is on Monday, Aug. 31.No usable supporting receipt — unverified.
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State Route 9 will have single-lane traffic near Kalloch Road (MP 59) with alternating signals for 42 days until Sept. 14 for fish passage construction.“009: SR 9 is reduced to a single lane near Kalloch Road (MP 59) with a signal alternating northbound and southbound traffic through a bypass road for 42 days, until Sept. 14 for fish passage construction.”
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A separate section near Mount Vernon Big Lake Road (MP 49) will alternate traffic weekdays from 10 a.m. to 4 p.m. through Sept. 3.“009: Northbound and southbound traffic will alternate from 10 a.m. to 4 p.m. daily Mondays through Thursday through Thursday, Sept. 3, just south of Mount Vernon Big Lake Road (milepost 49) for fish passage construction. Expect delays in the area.”
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WSDOT states the projects aim to improve infrastructureNo usable supporting receipt — unverified.
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Details about the projects are available on their project webpage.“More information on the <a href="https://wsdot.wa.gov/construction-planning/search-projects/sr-9-unnamed-tributaries-nookachamps-hansen-creeks-fish-passage">project webpage</a>.”
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Drivers should expect delays“Expect delays in the area.”
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Drivers should use detours where providedNo usable supporting receipt — unverified.