TheIl projectprogetto wasvenne conceivedstudiato innegli the[[anni 1970s70]] bydal theconsorzio di [[Boston Transportationper Planningla Review]]pianificazione todei replacetrasporti theper rustingrimpiazzare elevatedl'ingombrante six-laneArteria CentralCentrale Arterya sei corsie. TheLa tangenziale expresswayseparava separatedil downtowncentro fromcittadino thedalla waterfrontcosta, and was increasingly choked with bumper-to-bumper traffic. Business leaders were more concerned about access to [[Logan Airport]], and pushed instead for a third harbor tunnel. In their second terms, [[Michael Dukakis]] (governor) and [[Fred Salvucci]] (secretary of transportation) came up with the strategy of tying the two projects together—thereby combining the project that the business community supported with the project that they and the City of Boston supported.{{Fact|date=February 2007}}
Planning for the Big Dig as a project officially began in 1982, with environmental impact studies starting in 1983. After years of extensive lobbying for federal dollars, a 1987 public works bill appropriating funding for the Big Dig was passed by [[Congress of the United States|U.S. Congress]], but it was subsequently vetoed by President [[Ronald Reagan]] as being too expensive. When Congress [[Veto override|overrode]] his veto, the project had its green light and ground was first broken in 1991.<ref>Dan McNichol and Andy Ryan, ''The Big Dig''. Silver Lining Press, 1991</ref>
