7. Dulles Transit Extension (Texas)
Estimated Cost: $6.2 billion
Number 7 on our list of biggest construction projects in U.S. started back in 2008, and was scheduled to open in 2013. A chunk of the total cost was said to be shouldered by the federal government, while the rest is said to have been paid by the state. With 11 new stations and 23 miles of new track, there’s no doubt this transit extension is one of America’s biggest construction projects. It could also be a sign of things to come as the country looks to follow suite of Europe’s high-speed rail system.
weerasak saeku/Shutterstock.com
