The ARC plan would be the latest influx of cash designed to alleviate some of the world's worst traffic.

It follows a 2015 state plan to spend an extra $1 billion a year on road construction, as well as voter-approved plans in Atlanta, Fulton County and Clayton County to spend more on roads and public transportation. Fulton mayors are discussing a half-penny sales tax that could generate $4.9 billion over 40 years for transit projects, while Gwinnett officials are considering their own transit referendum.

“We can always use more money,” ARC Executive Director Doug Hooker told The Atlanta Journal-Constitution. “But with this injection of money, it’s a pretty significant investment.”

The commission serves as a conduit for federal funding of transportation projects in the Atlanta area. Most of the money for the six-year plan announced Monday – about $299 million – comes from various federal programs. The rest, $123 millon, is from local and state matching funds.

ARC received 123 requests from various government agencies for federal funding totaling $645 million. It whittled the list down, using a variety of criteria designed to decrease traffic congestion, improve air quality and enhance the safety and reliability of metro Atlanta’s transportation network.

Mass transit – especially local and regional bus service – would get an $86 million boost – about 20 percent of all funding. Though the plan contains no new MARTA rail projects, new and expanded bus services would begin in fiscal year 2019.

Among the transit projects included:

* MARTA would launch arterial rapid transit routes on Cascade Road, Cleveland Avenue, Campbelltown Road/Greenbriar, Metropolitan Parkway and Peachtree Road in Atlanta. The agency envisions them as “fast and frequent enhanced transit routes on existing high-density, mixed-use arterial corridors.”

*Gwinnett County would operate local bus routes past midnight on weekdays – the latest buses currently run until about 10:20 p.m. – and shorten the wait between buses to no more than 30 minutes for most of the day.

*Cobb County would add Sunday bus service and enhances existing Saturday service.

*Douglas County would launch local fixed-route bus service in Douglasville and elsewhere.

*The state's Xpress bus system would increase service along the Northwest Corridor Express Lanes in Cobb and Cherokee counties and expand park-and-ride lots in Gwinnett and Rockdale counties.

“This is probably the single-biggest investment in transit the region’s made in a long time,” Hooker said.

Under the ARC plan, road projects would get $213 million – about half the funding. Four projects on Gov. Nathan Deal's 10-year, $10 billion road-building plan would money for preliminary engineering: express lanes on the west and east sides of the Perimeter and the new I-285/I-20 interchanges.

Dozens of smaller highway projects also are included, from the South Barrett Parkway Reliever in Cobb County to a Ga. 81 widening in Henry County.

More than a quarter of the money – nearly $109 million – would go to bike and pedestrian trail projects. Atlanta Beltline extensions from Lindbergh Center to 10th Street and from Glenwood Avenue to University Avenue would get money for preliminary engineering.

Other projects would get money for construction, including sections of the Path 400 Trail in Atlanta, the Western Gwinnett Bikeway and the Dallas Battlefield Trail in Paulding County.

“It’s going to be a huge shot in the arm toward completing a true regional bike trail network,” Hooker said.

After soliciting public input, the ARC Board is expected to consider the plan in two phases this winter and spring.

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