Why is part of VA 168 tolled?

[cpzilliacus]

Some may see it as a cop-out, but the city is not wrong in that VDOT would require a fairly detailed study to consider a higher limit.  And it's quite possible that such a study would force the city to do improvements to the expressway before they could post a higher speed limit.  Some of the delays in VDOT posting higher limits on other routes (like 70 MPH on some Interstate segments) were due to them having to complete safety upgrades first.

The AADT on the tolled part of Va. 168 is low (but probably much higher in the Outer Banks tourist season) at only 9400, but dramatically higher at better than 70,000 near the I-64 interchange. 

Still, a higher speed limit on Va. 168 might also require an air quality conformity determination by the Hampton Roads Planning District Commission's staff.  Lowering speed limits do not trigger the need for a conformity determination.