Because of public outcry during construction of The Central Artery, elevated for most of its length and reviled because it cut off views of and access to Boston's historic waterfront, it was decided by then-Governor John A. Volpe that the final section of the artery was to be put underground from just south of Congress Street to Kneeland Street near Boston's Chinatown section.

The lack of breakdown lanes, the limited number of travel lanes, and the myriad access ramps to and from the Artery and the tunnel caused massive traffic jams and gridlock, forcing transportation officials to consider rebuilding the Artery and putting it totally underground.

The Dewey Square Tunnel received new life as part of the massive Big Dig project of the late 1990s and early 2000s.

The tunnel was rehabilitated and now serves as exclusive southbound lanes of Interstate 93, complete with a new ventilation system and gently banked corners consistent with appropriate superelevation.

Since the completion of the Big Dig project, the name "Dewey Square (South Station) Tunnel" has fallen into general disuse; instead, it is considered to be part of the Thomas P. O'Neill Jr.