At Dumfries Road, the Prince William Parkway assumes the SR 234 designation until ending at Interstate 66 (I-66) near Gainesville.

On February 16, 2012, the former route designation for the Prince William Parkway, SR 3000, was changed to SR 294 by VDOT when the Commonwealth Transportation Board approved the transfer of the secondary road to a primary road for better maintenance of the parkway.

The SR 294 portion from I-95 to its intersection with Liberia Avenue and SR 663 (Wellington Road) has been designated the Kathleen K. Seefeldt Parkway for Kathleen Seefeldt, the former chairman of the Prince William Board of County Supervisors.

As a part of the Transform 66 project, the current at-grade intersection of SR 234 and Balls Ford Road will be converted to a diverging diamond interchange at a cost of $167 million.

As a part of this project, Balls Ford Road will be realigned about 0.50 miles (0.80 km) south, where the interchange will be constructed, and a new grade-separated bridge will be built over the Norfolk Southern Railroad Line.