LOS ANGELES (CBS) — Construction crews will close the northbound San Diego (405) Freeway Tuesday night through a small stretch of the Sepulveda Pass to pour concrete for part of the Sunset Boulevard bridge over the freeway.

Crews will begin at 10 p.m. closing lanes and ramps on the northbound 405 between Montana Avenue and Moraga Drive. Traffic will be detoured to Sepulveda Boulevard, and the highway closure will remain in effect until 6 a.m. Wednesday.

Crews will also close Sunset Boulevard between Barrington and Veteran avenues for three consecutive nights starting Tuesday in order to pour the concrete for the north side of the Sunset Boulevard bridge.

The southbound 405 from Sunset to Wilshire Boulevard will be closed overnight on Friday to pour concrete for the section of the bridge over the southbound 405.

The bridge construction is part of a $1.2 billion widening project that will add carpool and exit lanes and make other improvements to the 50-year-old 405 Freeway between the Ventura (101) and Santa Monica (10) freeways.

The overall project is scheduled to be completed next year. It is being run by the Metropolitan Transportation Authority in cooperation with Caltrans.

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