"This is a long-awaited outcome," said Los Angeles County Supervisor Mark Ridley-Thomas, noting proposals for the transit corridor were first brought up 25 years ago.
"This project is long overdue and will provide congestion relief, improve air quality and serve as an economic catalyst," said Ridley-Thomas, who is also an MTA board member. "It helps bring a more rational and equitable transportation plan for the county of Los Angeles, and it means 7,800 new jobs."
The vote prompted cheers from hundreds of south Los Angeles residents who packed the Metro boardroom and two overflow rooms.
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At Ridley-Thomas' urging, the Metro board during a previous meeting moved up the timeline for the project, so that completion is expected between 2016 and 2018 -- instead of 2029.
Construction is to begin in 2012, pending results of the final environmental impact report due in late 2010.
This would be the first major transportation project to relieve congestion on the San Diego (405) and Harbor (110) freeways and other north-south arteries in western Los Angeles County.
It would also provide a major connection to LAX, connecting the Metro Green Line to the south with the proposed LAX Automated People Mover System and the Expo Line to the north.
The project would provide connection to the entire Metro Rail system and Metro's more than 2,000 peak-hour buses.
Funding will come from Measure R, the half-cent sales tax initiative approved by L.A. County voters last November to reduce traffic congestion, air pollution, and spur economic development.
The Metro board agreed to examine the cost of building a one-mile segment of the light rail line underground on Crenshaw Boulevard between 48th and 59th streets.