Safer Travel

The Bi-County Parkway will improve safety for Prince William and Loudoun county residents as well as other travelers.  Crash rates on limited-access roads like the Bi-County Parkway are typically two-thirds lower than those on undivided arterial roads like U.S. 15 and rural roads like Gum Spring Road.  (“Limited-access” means vehicles cannot enter or cross the road from driveways, unsignalized intersections or other unrestricted access points).  Reasons the Bi-County Parkway will be a safer road include:

  • Fewer conflicts with entering or crossing vehicles
  • A wide median separating opposing traffic
  • 10-foot safety shoulders
  • A straighter route with better sight lines

Currently, only a handful of two-lane roads allow drivers to travel north and south between Interstate 66 and Route 50.  Built decades ago and improved only slightly as the corridor has undergone significant development, roads such as U.S. 15 and Gum Spring Road are ill-equipped to handle current much less future traffic.


On these winding roads, high-speed traffic moves in opposing directions separated only by a double-yellow line.  Head-on collisions are not uncommon:  U.S. 15 in Loudoun County experienced 20 head-on collisions between mid 2008 and mid 2012.

Less Congestion

By providing a new four-lane facility between Route 50 and Interstate 66, the Bi-County Parkway will reduce congestion, enhance mobility and improve linkages between communities in the local area.  The new 10-and-a-half mile highway also will relocate the existing two-lane Route 234 out of the heart of Manassas National Battlefield Park, eliminating bumper-to-bumper congestion at the intersection with Route 29 and enhancing the experience for park visitors.

The Bi-County Parkway will carry a large amount of traffic that otherwise would use and overwhelm other local routes.  Specifically, the following roads will see reductions in congestion with the Bi-County Parkway in 2040:


Over the past two decades, Loudoun and Prince William counties have experienced some of the fastest growth in the nation.  Official forecasts show rapid growth continuing through 2040 in both counties:

  • 50 percent more residents will live in the two counties
  • 100 percent more employees will work in the two counties

As a result, trips between the two counties are expected to surge by 91 percent by 2040.