Loudoun County, Virginia, leaders are concerned about Dulles Greenway tolling data, which could be used to shape any upgrades along the corridor.
The Board of Supervisors voted last week to send a letter to the Virginia Department of Transportation pressing for tighter oversight of the company that operates the privately owned road under a 1993 agreement with the commonwealth.
It comes after the Greenway’s annual report on 2018 traffic found a decrease in road usage at the main toll plaza.
A county analysis submitted to the Greenway last month and presented to supervisors Thursday disputed the calculations though, instead finding an increase in rush hour use on the Greenway’s ramps in 2018 compared with 2017.
“It’s a positive value. It’s more cars getting into the ramps than the year before, but at the same time they are saying that they are having less cars inside of the toll facility,” county traffic engineer Enrique Gonzalez said.
The Greenway responded last month that its adjusted rush hour counts based on the tolling system were more accurate than the counts in the Greenway’s report that was used by the county.
Total toll transactions dropped 4.49% from 2017 to 2018.
“The facts should be agreed upon. They should be something that we all can agree via science and transportation science,” Supervisor Ron Meyer said.
VDOT has yet to accept or reject the report, which was completed in February based on October traffic counts. The busiest times are eastbound around 8 a.m. and westbound around 5 p.m.
If traffic counts are higher — leading to more delays at on- and off-ramps or elsewhere on the road — more widening or other improvements could be required.
“That’s an important thing: Trips that are going one or two stops up have not decreased; trips that are going the full length of the Greenway have decreased,” Board Chair Phyllis Randall said.
Backups at ramps like the Loudoun County Parkway could get worse as widening of the parkway is completed, likely drawing more traffic, the transportation department said.
There is a question about whether the Greenway is responsible for backups linked to ramps.
Meyer wants a formal agreement between the Greenway and VDOT on what improvements will happen. The Greenway is working on an expansion near the Dulles Toll Road, and is soon set to work on extending an exit lane to the Leesburg Bypass.
“We’re going to need to see more of that. As Metro comes, this is a key corridor around those stations,” Supervisor Matt Letourneau said.
The supervisors believe the Greenway is not meeting all requirements of its 1993 agreement with the state, because there are varying interpretations of what the agreement requires.
“I do appreciate the Greenway. It is nice to have that option. However, I believe the agreement has some pretty clear language that they are trying to wiggle their way out of, in my opinion,” Supervisor Tony Buffington said.
“If we need a long-term plan to get them back into compliance, so be it,” Meyer said.
The questions are separate from any uncertainty about future toll changes. A guarantee that the Greenway could increase tolls each year by slightly more than a measure of inflation expires next year.