The Big Dig was the largest and most complex highway project in US history, intended to solve Boston's traffic problems and reconnect downtown to waterfront towns. It involved constructing 7.8 miles of highway with 161 lanes miles through tunnels under the city. Over 22 billion was spent excavating over 16 million cubic yards of soil and pouring 3.8 million cubic yards of concrete with 5,000 workers. The project faced construction issues like leaks in the tunnel from faulty fixtures that killed one person, and cost overruns increased the price from $2.6 to $22 billion with taxpayers paying half.

1. Central Artery/Tunnel Project“The Big Dig”PROJECT 0GROUP 4Chris MinerSabah TasnuvaTingting LiuNicholas Johnson

2. What Is The Big Dig?“Largest, most complex, and technologically challenging highway project in the history of the United States”-Solution To Boston’s Traffic Problem-Reconnect Waterfront Towns To Downtown

3. Widest Cable-Stayed Bridge

4. WHY WE CHOSE “THE BIG DIG”A Big Part of Civil Engineering Involves Transportation

5. WHAT DID IT TAKE TO COMPLETE “THE BIG DIG”?1982-Environmental Impact Documents2007- Restoration of City Streets7.8 miles of highway, 161 lanes miles3.8 million cubic yards of concreteMore than 16 million cubic yards of soil excavated1999 through 2002, about $3 million of work completed each dayAbout 5,000 construction workers were on the job Jay Cashman, Modern Continental118 separate construction contracts, with 26 geotechnical drilling contracts.22 billion

7. CONSTRUCTION PROBLEMSFaulty Loose Fixtures:September 2004 - Water seeps through traffic barriers in Interstate 93 tunnel -Workers sandbagged one wall-Independent engineers hired to study problem -Reported that the tunnels may have more than 400 leaks

8. July 2006-39-year-old woman killed after 12 tons of cement ceiling panels fell on car.-Lead to investigation where federal and state officials uncovered additional problems almost on a daily basisBechtel: engineering, construction and management company’s reputation damaged

9. FINANCIAL PROBLEMS- Over the course of the Project, costs kept increasing- 2.6 Billion to 22 Billion- Taxpayers ended up paying half of the project’s costENVIRONMENTAL ISSUES-Downtown area through which the tunnels were to be dug was largely landfill and included existing subway lines as well as innumerable pipes and utility lines that would have to be replaced or moved.-Tunnel workers encountered many unexpected geological and archaeological barriers -Glacial debris -Foundations of buried houses and sunken ships