Infrastructure

I-405, I-90, I-5 Closures for Week of Sept. 1

Tuesday, September 1, 2026

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Multiple Washington State Department of Transportation (WSDOT) highway closures begin Monday for construction and utility work.

I-405 will see multiple nightly closures: up to two lanes southbound from milepost 12 to Coal Creek Parkway Southeast, up to two lanes northbound from milepost 7 to 8.5, and up to four lanes northbound from milepost 11.5 to 13.7. All will be closed 9 p.m. to 5 a.m. through Sept. 4.

I-90's eastbound off-ramp to Factoria Boulevard will be closed nightly through Sept. 4. I-5 will have reduced lanes near Alger/Lake Samish Road (exit 240) and a closed left lane northbound near North Lake Samish (exit 246), both for fish passage construction. SR 20 will have alternating traffic with flaggers from Swin Slough Bridge to Laconner Whitney Road/Bay View Road daily except weekends for city utility work. SR 4 will have single-lane closures weekdays for gas line work through Sept. 11.

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

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Multiple Washington State Department of Transportation (WSDOT) highway closures begin Monday for construction and utility work.“090: The eastbound I-90 off-ramp to Factoria Boulevard will be closed nightly, 9 p.m. Monday, Aug. 31 – 5 a.m. Friday, Sept. 4. A signed detour will be in place.”
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I-405 will see multiple nightly closures.“405: Up to two lanes of southbound I-405 from milepost 12 to Coal Creek Parkway Southeast (milepost 10) will be closed overnight, 9 p.m. Thursday, Sept. 3 – 5 a.m. Friday, Sept. 4. 405: Up to two lanes of northbound I-405 from milepost 7 to milepost 8.5 will be closed nightly, 9 p.m. Monday, Aug. 31 – 4:30 a.m. Friday, Sept. 4. 405: Up to four lanes of northbound I-405 from milepost 11.5 to milepost 13.7 will be closed nightly, 9:30 p.m. Monday, Aug. 31 – 4:30 a.m. Friday, Sept. 4.”
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Up to two lanes southbound on I-405 will be closed from milepost 12 to Coal Creek Parkway Southeast.“405: Up to two lanes of southbound I-405 from milepost 12 to Coal Creek Parkway Southeast (milepost 10) will be closed overnight, 9 p.m. Thursday, Sept. 3 – 5 a.m. Friday, Sept. 4.”
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Up to two lanes northbound on I-405 will be closed from milepost 7 to 8.5.“405: Up to two lanes of northbound I-405 from milepost 7 to milepost 8.5 will be closed nightly, 9 p.m. Monday, Aug. 31 – 4:30 a.m. Friday, Sept. 4.”
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Up to four lanes northbound on I-405 will be closed from milepost 11.5 to 13.7.“405: Up to four lanes of northbound I-405 from milepost 11.5 to milepost 13.7 will be closed nightly, 9:30 p.m. Monday, Aug. 31 – 4:30 a.m. Friday, Sept. 4.”
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All closures on I-405 will be closed 9 p.m. to 5 a.m. through Sept. 4.No usable supporting receipt — unverified.
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I-90's eastbound off-ramp to Factoria Boulevard will be closed nightly through Sept. 4.“090: The eastbound I-90 off-ramp to Factoria Boulevard will be closed nightly, 9 p.m. Monday, Aug. 31 – 5 a.m. Friday, Sept. 4.”
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I-5 will have reduced lanes near Alger/Lake Samish Road (exit 240) for fish passage construction.“005: The northbound and southbound I-5 will be reduced to a single lane from 8 p.m. to 5 a.m. nightly Monday, Aug. 31, through Friday morning, Sept. 4, near Alger/Lake Samish Road (exit 240) for fish passage construction.”
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A closed left lane northbound on I-5 will be near North Lake Samish (exit 246) for fish passage construction.“005: The left lane of northbound I-5 will close from 8 p.m. to 5 a.m. nightly Sunday, Aug. 30, through Friday morning, Sept. 4, north of North Lake Samish (exit 246) for fish passage construction.”
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SR 20 will have alternating traffic with flaggers from Swin Slough Bridge to Laconner Whitney Road/Bay View Road daily except weekends for city utility work.“Daily (except Saturday, Sunday) beginning Aug. 21 until further notice: State Route 20 traffic will alternate with flaggers from the Swin Slough Bridge (milepost 50) to Laconner Whitney Road/Bay View Road (milepost 53) for city Anacortes utilities work.”
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SR 4 will have single-lane closures weekdays for gas line work through Sept. 11.“004: Monday, Aug. 17 through Friday, Sept. 11: A single lane in both directions of SR 4 between 50th Avenue (milepost 56.4) and 42nd Avenue (milepost 57.2) will be closed weekdays from 7:30 a.m. to 5 p.m., for buried gas main line extension work.”