LOS ANGELES (CBS) — Southbound Pacific Coast Highway, now narrowed to two lanes in Pacific Palisades, will be opened up over “Carmageddon” weekend, transportation officials confirmed Tuesday.

One southbound lane has been closed to accommodate work on a dry-season runoff-diversion project, but that work will be suspended late Friday through early Monday, according to Lauren Skinner of the Los Angeles Department of Public Works.

Opening up PCH from Temescal Canyon Road and Chautauqua Boulevard should help alleviate some of the increased traffic from San Fernando Valley and Ventura County motorists using Topanga and Malibu canyon roads to bypass the closure.

Starting Friday evening, the San Diego (405) Freeway will be closed in both directions for 53 hours between the Santa Monica (10) and Ventura (101) freeways, so that the Mulholland Drive Bridge can be demolished to make way for a wider one to accommodate a carpool lane running from Orange County to the city of San Fernando.

PCH will be opened up to three lanes at least through Tuesday morning, then crews will replace the K-rails blocking the far-right lane, according to Skinner. The work, aimed at diverting dry-season runoff to the Hyperion sewage treatment plant, is scheduled to continue through mid-August.

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