Los Angeles completes major earthquake-resistant water pipeline project

The Los Angeles Department of Water and Power (LADWP) has completed the Foothill Trunk Line Project, replacing four miles of aging water infrastructure with a new earthquake-resistant pipeline. The original pipes, dating back to the 1930s, ranged from 24 to 36 inches in diameter. They have been replaced by a 54-inch-diameter line utilizing welded steel and ductile iron pipes equipped with flexible joints designed to withstand soil movement during seismic events.

LADWP officials described the project as the “largest and longest large-diameter earthquake-resistant ductile iron pipe installation in the nation.” The upgrade is part of a broader $8 billion, five-year capital plan to modernize the city's water system. Since 2012, the department has installed 67.2 miles of earthquake-resilient piping across Los Angeles.

Mayor Karen Bass and City Councilwoman Monica Rodriguez attended a press conference to mark the milestone, noting that the project enhances water reliability, improves quality, and protects critical services for first responders and local communities during potential disasters.