Bigdig project
The Big Dig was a massive infrastructure project in Boston that involved re-routing a major highway into tunnels underground to address traffic issues and reconnect downtown to waterfront areas. It included construction of new bridges and tunnels over more than 7 miles and cost over $22 billion, far more than initial estimates, due to unexpected geological and construction challenges. Problems included leaks in the tunnel and falling ceiling panels that killed a driver, damaging the reputation of involved engineering firms. It took over 20 years to complete and required excavating over 16 million cubic yards of soil and placing 3.8 million cubic yards of concrete with thousands of construction workers. Though costly, it aimed to solve transportation problems in the city.
Bigdig project
- 1. GROUP 4 Chris Miner Sabah Tasnuva Tingting Liu Nicholas Johnson PROJECT 0
- 2. 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 Art Underground 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
- 3. BRIDGES TUNNELS Leonard P. Zakim Bunker Hill Ted Williams Tunnel Leverett Circle Connector Thomas P. O’Neill Jr. Widest Cable-Stayed Bridge
- 4. 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
- 5. WHAT DID IT TAKE TO COMPLETE “THE BIG DIG”? 1982-Environmental Impact Documents 2007- 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
- 7. CONSTRUCTION PROBLEMS Faulty 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 basis Bechtel: 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 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