Infrastructure

Tri-Cities Roads Closed for Repairs Through Weekend

Wednesday, August 19, 2026

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Multiple road closures and lane reductions begin in the Tri-Cities area starting Monday, August 17, through Wednesday, August 19, for construction and repairs.

WSDOT announced the closures, including one lane of US 12 over I-5 closing nightly from August 10 to August 20, and southbound I-405 lanes closing from August 17 to August 19. SR 9 will be closed south of Mount Vernon Big Lake Road until 6 a.m. Wednesday, August 19, for fish passage installation.

Travelers should expect delays and follow detour routes as directed by flaggers. The closures are part of ongoing infrastructure maintenance and environmental projects.

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

Source receipts8 of 12 claims supported · 67%

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Multiple road closures and lane reductions begin in the Tri-Cities area starting Monday, August 17No usable supporting receipt — unverified.
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Multiple road closures and lane reductions continue through Wednesday, August 19“009: Both directions of SR 9 are closed until 6 a.m. Wednesday, Aug. 19, south of Mount Vernon Big Lake Road (milepost 49) to install a fish passage. Signed detours use SR 534, I-5 and SR 538/College Way around the closure. Please add time to your travel plans.”
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Multiple road closures and lane reductions are for construction and repairsNo usable supporting receipt — unverified.
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WSDOT announced the closures“WSDOT statewide highway construction and road closure updates — 8/18/2026:”
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One lane of US 12 over I-5 will close nightly from August 10 to August 20“012: From 7:30 p.m. Monday, Aug. 10 to 6 a.m. Thursday, Aug. 20: A single lane of US 12 over I-5 (milepost 66.5) will close nightly for bridge repairs.”
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Southbound I-405 lanes will close from August 17 to August 19“405: Up to three lanes of southbound I-405 from Coal Creek Parkway Southeast (milepost 9.5) to milepost 7 will be closed nightly, 10:30 p.m. Monday, Aug. 17 – 5:30 a.m. Wednesday, Aug. 19.”
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SR 9 will be closed south of Mount Vernon Big Lake Road until 6 a.m. Wednesday, August 19“009: Both directions of SR 9 are closed until 6 a.m. Wednesday, Aug. 19, south of Mount Vernon Big Lake Road (milepost 49) to install a fish passage. Signed detours use SR 534, I-5 and SR 538/College Way around the closure. Please add time to your travel plans.”
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SR 9 will be closed south of Mount Vernon Big Lake Road for fish passage installation“009: Both directions of SR 9 are closed until 6 a.m. Wednesday, Aug. 19, south of Mount Vernon Big Lake Road (milepost 49) to install a fish passage. Signed detours use SR 534, I-5 and SR 538/College Way around the closure. Please add time to your travel plans.”
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Travelers should expect delays“Slow down, stay focused and expect delays.”
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Travelers should follow detour routes as directed by flaggers“Flaggers will direct travelers to a signed detour using northbound I-5 to Exit 71 for SR 508, then southbound back to US 12.”
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The closures are part of ongoing infrastructure maintenanceNo usable supporting receipt — unverified.
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The closures are part of environmental projectsNo usable supporting receipt — unverified.