The Big Dig

The Central Artery/Tunnel Project of Boston (CA/T) was a mega-project that consisted of multiple projects in one: re-routing Interstate 93 (the Central Artery or the main highway through the heart of the city) into 3.5 miles of tunnel, constructing the Ted Williams Tunnel, Leonard P. Zakim Bunker Hill Memorial Bridge, and Rose Kennedy Greenway, and initially, connection the rail lines of Boston’s two main train terminals.  The completion of the entire project was scheduled to be in 1998 and total cost was supposed to be around $2.8 billion.

After escalating costs, leaks, design flaws, criminal arrests, charges of using substandard materials, continuous missed deadlines, and four deaths, the project became known as America’s Greatest Highway Robbery and is the most expensive highway project in the United States. Boston Globe estimated the total cost of the project to be $22 billion, including interest, and says it won’t be paid off until 2038; the people of Boston have paid for this construction through traffic accidents, almost daily, due to speed limits being extremely high and will continue to pay for it through taxes.

Boston, Massachusetts use to have a “world-class traffic problem.” The elevated six lane highway running through the center of downtown known as the Central Artery opened in 1959 and cut off Boston’s north end and waterfront neighborhoods from downtown. This alone, was affecting the city. The Central Artery carried approximately 75,000 vehicles a day when it first opened, and in 1990, that number rose to 200,000 vehicles a day. The accident rate on this elevated highway was four times the national average for urban interstates, and the same problem was occurring in the two tunnels underneath Boston. Without making any improvements to this major problem, it was expected that Boston would experience stop and go traffic jams for up to 16 hours a day by 2010.

The plans included changing the six lane highway into an eight to ten lane underground expressway, extending Interstate 90 to the Logan International Airport by a tunnel, constructing an additional bridge over the Charles River, and using the area from the previous Interstate 93 elevated highway for the Rose Kennedy Greenway.

The Ted Williams Tunnel was completed in December of 1995, and was named after a Massachusetts Congressman and Speaker of the House (1977-1987) that was an instrumental piece of getting the funding for the CA/T.

At the beginning of the project, the area from the elevated highway was a grey area as to what to do with it. There were continuous debates; no one wanted to take responsibility for the future, the government wasn't stepping up to make decisions, and of course, the money was a huge issue. Even though the project should have been completely planned before making any physical changes, such as tearing down the highway, the project was started and a void space was left for further decisions. Today, the area is known as Rose Kennedy Greenway and is owned by a non-profit corporation financed by state and public donations.

CA/T is a project that is considered to be on the same scale as projects like the Panama Canal, the Chunnel, and the Trans-Alaskan Pipeline. Each of these projects had their own challenges: The Panama Canal has earth slides, malaria, yellow fever, and Central American jungles; the Chunnel was dug 31 miles from opposite ends and met in the middle; The Alaskan Pipeline dealt with huge distances, freezing temperatures, and major environment concerns. The challenge of the Central Artery/Tunnel Project was trying to change the main highway going through the heart of the city without hurting the city in anyway; to do this, mitigation costs were one-fourth of the project’s budget.

During the peak of the construction (1999-2002), $3 million of work was completed each day, and 5000 construction workers were on the job. When the project was all said and done, the project totaled 7.8 miles of highway, 161 lane miles (half of that in tunnels), 14 on and off ramps (the elevated highway had 27), 3.8 million cubic yards of concrete, more than 16 million cubic yards of soil was excavated, and 29 miles of gas, electric, phone, sewer, water, and other utility lines were moved. On top of all this extreme design and actual work of the project, problems seemed to constantly occur, including: cost overruns and delays due to poor planning, insufficient materials, corruption within the project resulting in many people being charged, and investigations into these charges. Reasons that were reported for the cost overruns included inflation, the failure to asses unknown conditions of what was beneath the ground, environmental and mitigation, and expanded scope. With each of these issues came agreements that needed to be made and contracts between companies.

Although this project has a negative history and caused many problems through the extended time it took for completion, increased project cost, additional flaws, it is one of the largest, most technically difficult and environmentally challenging infrastructure projects ever in the U.S., includes the widest bridge ever built, and the first bridge to use asymmetrical design.

The achievements of this project vastly outweigh the flaws. The total vehicle hours of travel was reduced by 62% between 1995-2003 which provides approximately $168 million annually in time and cost savings to drivers, carbon monoxide levels were reduced city wide by 12%, mobility downtown was incredibly improved, neighborhoods that were cut off from downtown have been reconnected, and Boston’s quality of life has been increased. These are just a few of the benefits of tearing down the Central Artery and making the improvements for the city of Boston. Without these changes, Boston would not be what it is today; it would be over crowded and unsafe, if it even would still exist.