Why All Northwestern Loudoun Should Care about the Route 690/7 Interchange

By Maura Walsh-Copeland

In response to recent articles and letters, residents should know that the Route 690/7 Interchange will impact more than just the Town of Purcellville; it will impact all of northwestern Loudoun.

This interchange, on various developer and County plans for 30 years, has gone through many paths – literally.

The current interchange location is known as “Alternative 1” because the “Alternative 2” path – that had the interchange further west at Tranquility Road – was voted down in both 2007 and 2013 due to vocal public objection to the number of historic farms and homes to the north that would have been cut through or obtained through eminent domain.

The Alternative 2 path, depicted on maps given to the County dated 2004-2007 as “Route 9 Relocation West of Hillsboro to Rt 7 Bypass and Hillsboro Bypass Alternative,” was planned as a “toll road” from Route 9 to Route 7 west of Purcellville and beyond to the south, possibly to I-95.

This plan was considered by the Board of Supervisors in 2007 — after a similar effort east of Short Hill Mountain failed in 2006 due to litigation — but was removed after strong public opposition.

Perhaps other residents have wondered, as I have, why when Allder School Road was greatly widened and paved that a full-scale roundabout was built at Short Hill Road – at the same point the “toll road” was depicted to pass through.

Public input meetings for the Route 690/7 Interchange in 2013 attempted to bring back “Alternative 2,” which was again voted down. I questioned County Transportation consultants at that time about the traffic volume impacts the interchange would have on Hillsboro Road/Route 690, due to current issues of excessive speeding around blind curves (where sheriff speed guns have clocked traffic going 60-65mph around a 35mph blind curve near two intersections).

The response was that “15 percent of traffic (196 vehicles in the AM peak hour in 2020) would divert down Route 690.” It was pointed out to the consultants that the Town of Hillsboro was experiencing 17,000 vehicles, meaning 15 percent was 2,550 peeling off down Route 690 – significantly more than 196 vehicles.

Residents also questioned the traffic speed and intersection sight distance issues along Route 690 and were told “once design progresses, a speed study will be performed . . . speeding outside of the [interchange] study area is an enforcement issue” and “intersection [sight review] is outside of the scope of the study.”

At the 2018 public input meeting the County and its consultants were again told this interchange does not impact only Town of Purcellville traffic; it also impacts all County residents living on or on side roads to Hillsboro Road/Route 690, and that the current plans do not address the area wide safety, speeding, intersection line of sight and traffic volume concerns.

It wasn’t until the Route 9 Traffic Safety and Operational Study in 2020-2021 that we learned the actual expected traffic volumes. The consultant report showed an expected increase of traffic on the north-south routes of 5,500 down Hillsboro Road, with ranges from 31 percent to 75 percent by 2030, and 50 percent to 192 percent by 2040 for other routes on the west side of Short Hill.

The conclusion of the Route 9 Safety Study was that four-laning Route 9 would not be necessary, because once the Route 690/7 Interchange was open, traffic would peel off down north-south routes of Cider Mill and Stony Point Roads to Woodgrove and Allder School Roads on the west side of Short Hill Mountain and down Hillsboro Road to the east side.

With this disclosure, Task Force members asked what will be planned and were told traffic calming mitigation for the north-south routes was (again) “out of scope” for the Route 9 study.

As members of that Task Force representing east and west of Short Hill Mountain, I with John Lovegrove wrote a “Citizen’s Report Requesting Traffic Calming for the North/South Routes.” The County did include a short study on Hillsboro Road/Route 690 with proposed road striping improvements and vegetation removal, but other traffic calming recommendations (including roundabouts) would have to “wait and see” impacts after the interchange is opened.

We were thankful Supervisor Buffington was able to secure funding for the minor improvements for Hillsboro Road, and have a similar study approved for Cider Mill, Stony Point and Woodgove Roads. However, it is not clear whether the studies and improvements will be implemented before the opening of the Route 690/7 Interchange.

Which leads back to the recent issues and questions.

In general, I favor the use of roundabouts for improved traffic flow. But were the plans to change the interchange from traffic lights to roundabouts in 2019 due to anticipated volume backups from the north-south routes?

Will the County assure residents that the Cider Mill/Stony Point/Woodgrove Road study and Hillsboro Road traffic calming improvements will be completed before the interchange is open?

As a consultant I understand the concept of “out of scope.” But will the County produce reports that show the interdependence of the timing of each of the efforts with the proper sequencing?

The Town of Purcellville has the obligation to review the interchange plans for its residents; the County has the obligation to review and sequence all transportation efforts for the health, safety and welfare of the entire northwestern Loudoun extended community.

Former Mayor Fraser recently commented on the “overall poor planning and coordination by the County on this project.” He also commented that, “the question is velocity versus speed,” saying “velocity has process and has direction. Speed is just going mindlessly.” I will add that speed, in the form of unmitigated traffic on rural roads with blind curves, can also kill.