Transform I-66 Outside the Beltway

The Transform I-66 Outside the Beltway (OTB) Project is one of the largest transportation undertakings in Northern Virginia, delivering $3.7 billion in improvements across a 22.5-mile stretch of I-66 from I-495 (Capital Beltway) to Gainesville. Delivered as a public-private partnership between VDOT, the Department of Rail and Public Transportation (DRPT), and private partner I-66 Express Mobility Partners, the project transformed the corridor into a modern multimodal system built to move more people and provide more reliable trips.

The scope included new express lanes alongside the regular lanes, expanded transit and park-and-ride options, upgraded and replaced interchanges, new and rehabilitated bridges, sound barrier walls, and improved bicycle and pedestrian connectivity across the corridor. Together, these improvements were designed to relieve one of the region's most persistent congestion points while offering commuters new travel choices.

Dulles Engineering provided construction quality control services throughout the project, working closely with design-build contractor FAM Construction and VDOT. DE's scope included field and environmental inspections, materials testing, and a range of specialized pavement testing — including Lightweight and Falling Weight Deflectometer (LWD/FWD), International Roughness Index (IRI), Windsor Probe, skid resistance, Critical Condition Index, and rebound hammer testing. Through this work, our team helped ensure all construction met or exceeded project specifications, safety standards, and environmental regulations.

By enhancing regional mobility, reducing congestion, and expanding commuter options across the corridor, the Transform I-66 OTB Project reflects the kind of large-scale, multimodal infrastructure delivery that defines modern transportation investment in Northern Virginia.

VDOT

FAM Construction

Fairfax and Prince William Counties, Virginia 

Late 2017 - November 2022

• Quality Control Management and Inspection Services
• Field and Environmental Inspections
• Materials Testing and Inspections
• Specialized Pavement Testing (LWD, FWD, IRI, Windsor Probe, Skid Resistance, Critical Condition Index, Rebound Hammer)