Raleigh, N.C. — Leaders from six area counties agreed on Monday to a long-term plan to help balance growth with area transportation needs.

Details of the Special Transit Advisory Commission's recommendations will include commuter rail and busing systems and having more than 55 miles of roadway spanning Wake, Durham and Orange counties in place by 2020.

"The Triangle area is projected to double in size over the next 20 to 25 years, and that growth means major congestion unless we do something about it now," said STAC co-chairman George Cianciolo said.

The first phase of the plan would make four connections in the Triangle:

• Chapel Hill to Durham
• Durham to North Cary
• North Cary to North Raleigh through downtown Raleigh along the U.S. Highway 1 corridor
• Raleigh-Durham International Airport to Research Triangle Park

The system is expected to cost approximately $2 billion, with 75 percent of funding from a sales-tax increase of up to a half percent and possibly an additional vehicle tax.

The federal government would cover the rest of the funding.

STAC will work on its recommendations and finalize them by Feb. 29, when they will then go to local transportation leaders for consideration.