LOS ANGELES (CBS) — Overnight closures of the San Diego (405) Freeway through the Sepulveda Pass, which had been originally scheduled for last week, were slated to take place Friday and Saturday nights.

Crews were expected to close northbound lanes of the 405 late Friday night from Getty Center Drive to Ventura Boulevard for the continuing construction of a new bridge across the freeway at Mulholland Drive.

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Metro also planed similar southbound closures for Saturday night from the Ventura (101) Freeway to Getty Center Drive if weather permitted.

Metro was expected to begin closing on- and off-ramps as early as 7 p.m. and planned to start lane closures at 11 p.m.

Sepulveda Boulevard will remain open next to the freeway during the closures as an alternate route.

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Crews expected to have the freeway reopened by 6 a.m.

The closures were taking place to allow contractors to construct scaffolding above the freeway, next to the remaining half of the old Mulholland Drive overpass.

The other half of the bridge was demolished last summer during a weekend dubbed “carmageddon”.

The bridge work is a necessary 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 101 and the Santa Monica (10) Freeway.

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

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