Central Artery/Tunnel Project

GROUP 4Chris Miner

Sabah TasnuvaTingting Liu

Nicholas Johnson

“The Big Dig”

PROJECT 0

What Is The Big Dig?

OLD CENTRAL ARTERY (I-93)

NEW CENTRAL ARTERY (I-93)

6 Lane Elevated Artery 8-10 Lane State of the ArtUnderground Highway

“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

BRIDGES TUNNELS

Leonard P. Zakim Bunker Hill Ted Williams Tunnel

Leverett Circle Connector Thomas P. O’Neill Jr.

Widest Cable-Stayed Bridge

WHY WE CHOSE “THE BIG DIG”

TRANSPORTATION LOCAL PROJECT

Tunnels Classmates Can Relate

Bridges Classmates Have Seen It

Highways Classmates Have Used It

A Big Part of Civil Engineering Involves Transportation

WHAT DID IT TAKE TO COMPLETE “THE BIG DIG”?

1982-Environmental Impact Documents2007- Restoration of City Streets

7.8 miles of highway, 161 lanes miles

3.8 million cubic yards of concrete

More than 16 million cubic yards of soil excavated

1999 through 2002, about $3 million of work completed each day

About 5,000 construction workers were on the job Jay Cashman, Modern Continental

118 separate construction contracts, with 26 geotechnical drilling contracts.

22 billion

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

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 basis

Bechtel: engineering, construction and management company’s reputation damaged

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 cost

ENVIRONMENTAL 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