Excavation for the $700M Lake Mead Intake No. 3 Project was put on hold after tunneling encountered a fault carrying groundwater that flooded the excavation and submerged equipment. The flooding occurred over about 4-days, so there were no injuries reported. The Southern Nevada Water Authority ‘Third Straw’ project will secure the Lake Mead water supply for thirsty Las Vegas in the face of declining lake levels. The contractor will drill into the fault and grout it so the water can be pumped out and work can proceed. Check out this interesting SNWA project overview video for the ‘Third Straw’ project. [Source: Las Vegas Sun via ASCE SmartBrief. Image: Southern Nevada Water Authority]
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This post describes the relatively recent Claremont Tunnel Seismic Upgrade Project as reported in Civil Engineering Magazine (May 2008, v. 78, no. 5, pp 58-63, 96-97).