Section Design Consultant: HNTB Corporation

The U.S. Route 1 Interchange project involved the complete reconstruction of the existing interchange including replacement of all ramp movements, addition of ramps connections to future HOV lanes, ramp connection to Eisenhower Valley at Mill Road, retaining walls, sound barrier walls, extensive ground improvement program along the northern and southern limits of the mainline roadways, electrical transmission tower relocation, bridge replacement and widening of the I-95/I-495 mainline roadway section from 0.91 miles west of U.S. Route 1 to the west abutment of the new Woodrow Wilson Bridge at Royal Street.

Improvements along U.S. Route 1 include roadway widening and reconstruction, bridge reconstruction, intersection improvements and utility relocations from Franklin Street on the north to Huntington Avenue to the south. Environmental mitigation improvements include the Urban Deck over the I-95/I-495 mainline at Washington Street, improvements to Jones Point Park and creation of wetlands at several locations adjacent to the interchange.

The U.S. Route 1 Interchange project includes typical types of construction elements found in a modern highway interchange reconstruction project under traffic. Approximate quantities of specific construction elements for this interchange include the following:

• 28 Lane Miles of Roadway Improvements
• 33 Vehicular Bridges
• 17,936 SF of Retaining Walls and potentially 9,261 SF of Sound Barrier Walls

The reconstruction of the U.S. Route 1 Interchange had unavoidable impacts to aquatic resources of the Cameron Run stream, Hunting Creek and the Potomac River. On-site wetland mitigation construction at several adjacent locations was included in the project scope. Widening of the I-95/I-495 Mainline at Washington Street displaced one Hunting Towers high-rise residential unit, Hunting Terrace low-rise residential units and 2 office buildings.