NCDOT says it now will allow truckers to haul twin-trailer rigs on freeways in the Triangle and Eastern North Carolina where they were not allowed before:
* The Durham Freeway (N.C. 147) from Interstate 85 in northern Durham to Alexander Drive in RTP
* U.S. 64 between U.S. 15-501 near Pittsboro and U.S. 1 in Cary
* U.S. 64 from U.S. 13 / 15 in Martin County to N.C. 94 in Tyrrell County
* N.C. 148 (Felix Harvey Parkway) between N.C. 58 and U.S. 70 in Lenoir County.
* The southern half of Raleigh's 540 Outer Loop, most of which has not been built yet. The loop eventually will extend from Interstate 40 near Research Triangle Park to U.S. 64 / 264 at Knightdale. [Updated 1/11/12]
State law requires NCDOT to withhold permission for twin trailers to use a route until it has conducted a traffic engineering study to show that the route can handle the traffic safely.
Twin-trailer permission is pending for the first section of the Triangle Expressway, which extends N.C. 147 south through RTP to the 540 Outer Loop.
Trucking companies do not need state approval to drive twin trailers on interstate highways, including the northern 540 Outer Loop, and certain other fedeeral routes.