http://www.youtube.com/watch?v=NPkWAGm3HFw. This is PRICELESS.
Living in Broadlands, VA; Working at Half & L SE, DC.
"JDC"
http://www.youtube.com/watch?v=NPkWAGm3HFw. This is PRICELESS.
At the beginning they show a earth boring shield being lowered into a shaft adjacent to the Watergate on Virginia Avenue NW. I did not arrive in Washington until after the Potomac River tunnels between Foggy Bottom and Rosslyn were excavated. That being said I was always under the impression those tunnels transitioned from earth shield boring to hard rock mining somewhere between the Foggy Bottom station and 26th Street until I saw the excavation for the expansion of the George Washington Hospital next to the Foggy Bottom station back January of 2009. The top of the bed rock in the area of the Foggy Bottom station is in the area of 5' above the level of the mezzanine in the station east of 23rd street. At that time I came to the conclusion that the entire length of the tunnels were hard rock mined. Seems I was correct all along, the difference being is it transitions from hard rock mining west of the Foggy Bottom station to a short segment of earth shield boring in the area of 27th street before transitioning back to rock mining to go under the river.
The production of the film was probably commissioned by Cody Phanstiehl when he was director of the WMATA Office of Community Service during that era. During the time I worked as as volunteer aiding Cody in the conducting of the tours of the construction this film was not shown prior to making the tunnel walk. I have never seen the film until now.
I will also noted that the film was produced before the hard rock tunnel boring machine was put into service boring the tunnels on the A Route Red line under Connecticut and Wisconsin Avenues between Rock Creek and Pooks Hill Road.
