The District of Columbia Water and Sewer Authority (DC Water) recently christened a new Tunnel Boring Machine ‘Lady Bird’ in honor of former first lady Claudia Alta ‘Lady Bird’ Taylor Johnson. The roughly 23-ft diameter TBM will tunnel a total of over 24,000 feet at a depth of 100 feet below the Potomac and Anacostia Rivers as part of a DC Water project aimed at reducing combined sewer outfalls. I first posted about this project, including a Google Map of the route a few years back. [Source: More at Tunnel Business Magazine. Image: Tunnel Business Magazine]
The tunnel replacing the Alaskan Way Viaduct (SR-99) will pass beneath 158 existing structures requiring an extensive program of vibration and settlement monitoring as well as some remediation. Of the 158 buildings, WSDOT identified 20 […]
Thanks to approximately $100 million from President Bush’s proposed 2009 budget, the $1.8 billion project creating a light-rail line from downtown Seattle to the University of Washington is likely to break ground some time this year. The project will involve twin bored tunnels on the order of 3 miles in length. It is scheduled to open for use in 2016.
There is another notable tunnel project associated with the Seattle Light Rail, known as the Beacon Hill tunnel which I have blogged about before.