Bob Malme in a post to a regional transportation forum noticed that on a map of the now under construction Triangle Expressway thatthe NC 147 TOLL and NC 540 TOLL shields were purple. Any non-toll NC routes were the traditional black background. Bob references the 2009 NC Turnpike Annual Report which shows a map of the TriEx on page 17.
This would confirm a note I received informing me that at an unrelated meeting to the Turnpike, an NCDOT official said that local communities couldn't use purple for wayfinding projects because it is reserved for the upcoming toll roads.
The reason for purple? The FHWA Manual of Uniform Traffic Control Devices (MUTCD) requires it. From page 10 of the 2009 Edition of the MUTCD:
The Triangle Expressway will be completely tolled electronically. Most likely a 'TOLL' banner will be included above the 540 and 147 shields.J. Purple—lanes restricted to use only by vehicles with registered electronic toll collection (ETC)
So of course, the question is - What do you all think? Do you like the use of purple in a state highway shield? Have better suggestions? Your own prototype you'd rather suggest? Post and send away....