LA tunnel work at 'full stop' following collapse, ongoing investigation
Construction work on an LA wastewater tunnel project remains paused following a partial collapse earlier this month in which nearly 30 workers were trapped, and later rescued.

According to Construction Dive, the July 9 collapse was attributed to high ground pressure in the area, and investigation into the incident is ongoing.
See also: 31 workers rescued after LA tunnel partially collapses
Local sanitation officials stated that the tunnel boring machine has in place where it stopped working prior to the collapse, and no one has yet been allowed to enter the tunnel or assess the breach location.
The investigation into the breach of the Los Angeles Effluent Outfall Tunnel is ongoing, Construction Dive reported. The tunnel boring machine had advanced 4,100 feet away from this initial squeezing area when the partial breach occurred 370 feet below ground, according to the letter. Flatiron/Dragados is currently working on an access plan for the tunnel, and more answers will become available once crews can reenter.
The $630 million tunnel, which broke ground in 2019, is part of the Sanitation Districts’ Clearwater Project to protect local waterways, according to the project website. The new 7-mile tunnel will transport treated wastewater to the ocean and will replace two aging tubes. It will be built to current earthquake standards and with enough capacity to protect against overflows from major storms.
Work was expected to be completed in 2027 but it is not yet clear how much the breach will delay the project, according to the letter. Construction prep work at the tunnel boring machine arrival location at Royal Palms Beach in San Pedro continues as scheduled, according to Chee.
A town hall meeting to give updates on the investigation and timeline is scheduled for Aug. 9, according to the project website.
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