Summer traffic along two major freeways is about to go from bad to worse as workers begin construction on improvement projects.
The Los Angeles Metropolitan Transportation Authority is urging motorists to consider alternate routes during a 53-hour, 10-mile closure of the 405 freeway, between the 101 and 10 freeways during the weekend of July 16-17.
Traffic conditions on freeways and streets in the area are expected to be severe with significant, multi-hour delays, according to Metro.
The ramps could be shut down as early as 7 p.m. Friday and the closure could begin as early as 10 p.m. to begin demolishing the Mulholland Bridge, as part of the Sepulveda Pass Improvements Project, according to Metro.
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The Getty Center museum will be closed to visitors and most staff during that time since access to the area will be essentially eliminated.
Meanwhile, crews are beginning work to bury 3,100 feet of new sewer pipe under
the Pacific Coast Highway in Pacific Palisades and Santa Monica. Barricades are set to go up this week, and one of the three southbound lanes will be closed for two months, Los Angeles officials said.
The project is designed to divert polluted runoff from canyons and flood control channels.
As work progresses, the closed section will creep a half-mile from Potrero Canyon to the Santa Monica city limits. Most of the work is expected to take place overnight.
Between 9 p.m. and 5 a.m. weekdays, digging equipment and trucks will be on the site, and just one southbound lane will be open. Signs along the 101 Freeway in the San Fernando and Conejo valleys warn commuters of the coming congestion.
Northbound traffic will be unaffected. A temporary bridge and bike lane detour have been set up at Santa Monica Canyon for foot and cycle traffic.
The new sewer line, 3-feet in diameter, will carry runoff near the coast to existing sewer mains that feed the Hyperion Sewage Treatment Plant just south of Los Angeles International Airport.
The project is being paid for with a $500 million bond issue approved by Los Angeles voters to reduce pollution in Santa Monica Bay.
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