Under a general engineering services contract for Loudoun
County, B&N prepared traffic studies to determine the potential impacts a new commuter
rail transit station and an associated new bridge would have on the planned roadway
system in a rapidly developing area in Loudoun County, Virginia. The Route 772 Connector
Bridge, expected to be completed in 2020, will cross over a new metro line and the
four-lane Dulles Greenway toll road. Metro stations will be located adjacent to
two new developments - Moorefield Station and Loudoun Station.
Before the bridge was planned, traffic studies had been completed and approved for
both developments. Recent studies conducted by B&N compared the traffic operations
of the approved roadway network to the newly proposed network with the Route 772
The study included a total of 39 intersections – 31 at Moorefield Station and eight
at Loudoun Station. The B&N team analyzed the traffic impact for each development
using four different scenarios – existing conditions, no build conditions, build
conditions with the bridge and build conditions without the bridge.
Study results found that there was not a significant difference between the estimated
operation of the approved roadway network and the alternate network with the bridge.
B&N recommended minor revisions to the existing traffic plans. Recommendations included
a number of new turn lanes, new and modified roadway approaches and changes to traffic
control at several intersections.