By CBSLA Staff

ANAHEIM HILLS (CBSLA) — The westbound 91 Freeway will be completely closed Friday evening between Corona and Anaheim Hills as part of an ongoing improvement project.

(credit: Riverside County Transportation Commission)

From 11 p.m. on Friday through 5 a.m. on Saturday, all westbound lanes on the 91 between the 71 Expressway and Highway 241 will be shut down, according to the Riverside County Transportation Commission.

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The agency said the closure is required for crews to safely remove signage connected to a 91 corridor expansion project that’s nearing completion.

A four-mile stretch of the freeway will be out of service. Motorists are advised to consider exiting the 91 at the 71 interchange and taking the expressway north to the 60 Freeway, then turning south on the 57 Freeway, which intersects westbound 91 on the Orange County side.

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Other roadways will be closed starting at 10 p.m. including the westbound Green River Road on-ramp and off-ramp, the southbound 71 to westbound 91 connector, and the westbound 91 Express Lanes in Riverside and Orange counties.

RCTC officials warned of possible significant travel delays for anyone trying to head west on the 91 through Corona and into Orange County Friday evening.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)