The estimate was conducted by the accounting firm of Deloitte and Touche and, according to Rita Strazzeri, spokesperson for the Massachusetts Turnpike Authority, is almost the same amount as the internal review conducted by the Authority. "It's a good sign that they came close together," she tells GlobeSt.com.

The estimate states that the Big Dig will cost $100 million more than was previously estimated and comes a month after the MTA revealed $300 million in new overruns. The cost for the project is now up to $14.475 billion.

Both the Federal and the state legislature have stated that they will not provide any more funds for the project. The Authority has been conducting public hearings on a potential toll hike, which, notes Strazzeri, "people were mostly opposed to." Still, the board of the Authority will vote on the increase on September 11 and if it agrees to the hike, it will go into effect this January.