Grouting work done earlier in the week was a possible cause of a bulge in the lining of a train tunnel under the River Thames. Two trains hit the bulge before the line was closed, but neither train derailed. [Source: New Civil Engineer]
Project Related
Rising Costs and Delays in Seattle Area Wastewater Plant and Tunnels
In keeping with our theme of rising costs on tunnel projects, the Brightwater sewage-treatment plant and treated waste pipeline project in King County Washington (Seattle area) is now up to at least $1.84 billion according to the lead consultant on the project. The treated waste pipeline is 13 to 14-miles long and at depths of 40 to 440-ft! It is being constructed nearly entirely by TBM. One source of delay was due to a tunneling subcontractor not being able to get parts (ball bearings?) because they were all being requisitioned by the US War Department for use in military equipment in Iraq and Afghanistan. Click through for information sources and links.
Project Related
Hidden challenges of Highway 99 tunnel (Seattle’s Alaskan Way Viaduct Replacement)
The proposed tunnel to replace the seismically deficient Alaskan Way Viaduct in Downtown Seattle is no stranger to controversy. This article highlights recent discussions regarding the cost of the project. Washington Governor Chris Gregoire declared […]
Miscellaneous
Port Authority Covers Hudson Subway Tunnels with Blast Shields to Protect Against Terror Attacks
The century-old PATH subway tunnels underneath the Hudson River were not excavated through bedrock, but rather under a thick layer of silt and clay. Apparently there is a a sufficient security concern to warrant protecting […]