Wilmington tunnel collapse temporarily traps 31 construction workers

A tunnel under construction in Wilmington on Wednesday night temporarily trapped 31 workers who were successfully rescued, fire officials said.

The L.A. Fire Department said the tunnel workers had been isolated by a "collapse" in an industrial tunnel for a wastewater treatment facility. The workers, fire officials said, were trapped as many as 6 miles south of the only access point located the 1700 block of North Figueroa Street in the Harbor-area L.A. neighborhood.

LAist media partner KCAL News reported that construction workers were being hoisted from a crane to the surface at roughly 8:55 p.m. before the collapse occurred. Shortly before 10 p.m., the LAFD said all the workers had been safely removed from the tunnel "alive without visible injury."

Fire officials said the workers in the 18-foot diameter tunnel were able to scramble onto a pile of loose soil on the other side of the collapse to be shuttled "several at a time by tunnel vehicle to the entry/access point."

The $630.5 million Los Angeles Effluent Outfall Tunnel project was commissioned by the Los Angeles County Sanitation District. The sewage pipe being worked on will feed the Hyperion plant, which according to the sanitation district is the city's oldest and largest wastewater treatment facility, having operated since 1894.

According to Flatiron Dragados, the project's contractor, the 7-mile, 18-foot-diameter tunnel will "safely transport treated water from the Hyperion Water Reclamation Plant to the Pacific Ocean."

The Hyperion plant is part of Los Angeles' ongoing plans to recycle more wastewater. A decades-long project is expected to eventually provide 50% of the city's drinking water.