Lorton task force: staff warns road‑diet would worsen peak congestion, recommends targeted fixes instead

Fairfax County transportation staff told the Lorton Vision Task Force on the evening’s meeting that a proposed conversion of Lorton Road from six lanes to four would not remove enough traffic and would substantially worsen PM peak congestion, based on a 2045 travel‑demand forecast used for the study.

Tom Burke, senior transportation planner with Fairfax County Department of Transportation, said the team ran sensitivity tests comparing the adopted comp plan baseline and the task‑force preferred land‑use scenario. "We ran it with six lanes and we ran it with four lanes," he said. "There's about a thousand trips difference on Lorton Road — the volumes with Lorton six and Lorton four don't change all that much," he said, adding the westbound PM volume‑to‑capacity ratio approached 1.54 and delays rose roughly 50 percent in critical segments.

The modeling showed roughly 33,000 daily trips on the segment approaching I‑95 under the six‑lane case, dropping to about 32,000 under the four‑lane sensitivity test, staff said. Burke told the group that because few viable alternative routes exist, drivers largely remained on Lorton Road even after capacity was cut, increasing congestion and queueing. "Based on the modeling, people are still going to cut through here," he said, and staff therefore did not feel it would be responsible to recommend a cross‑section change that increased peak delay by half.

Task force members pushed back that the exercise should prioritize Lorton residents’ quality of life and local walkability. "I just want to make sure that we're seeing this as a Lorton vision task force and therefore I wanted to put in somewhere in here that the goal is to reduce Lorton as a cut‑through," said one member who identified herself as Dale, arguing the plan should emphasize local outcomes over regional through‑traffic. Another member, Christine, said that four lanes could enable a more pedestrian‑friendly boulevard if alternative routing and design measures accompanied a road diet.

Staff emphasized the comprehensive plan amendment is advisory and not regulatory and said the task force can adopt a community‑focused recommendation while staff must also be able to justify the transportation implications to VDOT and regional partners. "The comprehensive plan is not law," Steve Waller of the Department of Planning and Development told the group; he said staff would record the task force’s preferences and escalate concerns about lane widths to VDOT as part of the plan record.

The meeting also included discussion of modeling assumptions. Members asked whether the forecast incorporated planned I‑95/interchange improvements; staff confirmed projects in the Council of Governments constrained long‑range plan were included in the 2045 model. Several participants raised recurring local backups tied to Amtrak's Auto Train loading, which typically causes midday and seasonal queues that the model (focused on AM/PM commute peaks) did not capture. Burke said Auto Train loading impacts would need separate coordination with Amtrak and VDOT.

Next steps: staff will refine maps and plan text and return to the task force at the March 16 meeting for a final recommendation that will be included in the staff report for later planning commission and Board of Supervisors public hearings.