A google search for the largest development projects in the United States nets a top ten list from Building Connected, a developer of pre-construction solutions.

Number six and nine include a viaduct replacement tunnel in Seattle and the Hudson Yards development project in New York City. Each project costs more than a billion USD and is worth exploring in greater detail.

The Alaska Way Tunnel

The Alaska Way Tunnel is a giant underground tunnel to replace a viaduct that carried hundreds of thousands of vehicles in Seattle Washington. The total estimated cost of the project is 3.29 Billion, with 2.8 Billion coming from State and Federal Governments.

The project includes a 1.7-mile tunnel drilled by the world’s largest tunnel boring machine.

New York’s Hudson Yards

Hudson Yards is a project with more than fifteen structures in the Chelsea neighborhood of Manhattan. The estimated cost is upwards of 25 billion with Related Companies and Oxford Properties controlling the development.  

Some criticisms of the project include architectural inconsistency and the lack of affordability within the development.

The economics of megaprojects was studied by McKinsey “Megaprojects: The Good, The Bad, and The Better.” McKinsey explores how megaprojects can account for a significant portion of the local economies GDP growth and estimates that about fifty-seven trillion of infrastructure will be needed by 2030 to “enable the anticipated levels of GDP growth globally.”

Megaprojects facilitate commerce and economic growth, however, are highly risky. They can experience cost overruns and lose public support and trust.

Photo Courtesy Wikimedia Commons Epicgenius