One hundred feet below Washington, D.C.’s Potomac and Anacostia rivers, “Lady Bird” is hard at work. The 442-foot-long tunnel boring machine (nicknamed after Lady Bird Johnson, the former First Lady and environmental activist) is chewing up clay to create 13 miles of tunnel with an inside diameter of 23 feet to hold sewage awaiting the Blue Plans Advanced Wastewater Treatment Plant. On this project, Skanska is part of a joint venture with Traylor Brothers and Jay Dee Contractors.
This tunnel and others like it are the centerpieces of a massive effort to clean up the waterways in the D.C. area. With the configuration of D.C.’s sewer system, the same pipes carry both storm water run-off and sewage from homes and businesses. This leads to harmful discharges of raw sewage into the rivers during periods of heavy rains. Having this storage conveyance tunnel – and a subsequent nearly nine-mile stretch – will help prevent such occurrences. This mammoth project is one of the most ambitious projects in the D.C. area since the Metro was built starting in 1969. It recently won the Technical Innovation of the Year award from the International Tunnel Association.
So, what’s it like to burrow 100 feet below the nation’s capital? D.C. Water released a video of Lady Bird in action, which The Washington Post recently featured on their site. Check it out here: