Los Angeles Department of Water and Power crews Monday continued pressure testing a new section of the water main that ruptured and flooded parts of West Hollywood, damaging cars, homes and businesses and shutting down traffic along the Sunset Strip.
Workers have made “significant progress” replacing the broken section of the 110-year-old trunk line that sent 17 million gallons of water into the streets of West Hollywood last week, but a major section of Sunset Boulevard remained closed Monday.
Repairs of the 36-inch main were completed Sunday night as a new 25-foot section was welded into place.
“The pipeline is currently being repressurized as crews continue detailed inspections to verify integrity and ensure zero leaks remain before moving forward,” according to statement released by the LADWP Monday morning, that went on to say “the multi-day restoration effort involves precise technical procedures designed to protect water quality, structural safety, and reliability for the community.”
A section of the circa-1916 water main broke open at 3 a.m. Thursday on Sunset Boulevard at Holloway Drive, pushing around cars and flooding garages while shifting massive chunks of asphalt and concrete slab. A number of vehicles were visibly damaged and others were flooded nearly to their roofs in subterranean parking.
By 7 a.m. Thursday, the rushing water, which sent debris all the way to Santa Monica Boulevard, had been stopped.
“Repairs are anticipated to continue into this week, and we understand the ongoing difficulties and disruptions this has caused for residents and businesses across West Hollywood,” the utility said in its latest update. “LADWP is fully committed to advancing pipe repairs and restoring affected streets as quickly and safely as possible.”
According to the department, the line will not be returned to service “until every regulatory and internal safety benchmark is met.
“Late yesterday (Sunday), crews successfully sealed any leaks discovered during pressure testing. With that repair complete, the pipeline is being carefully repressurized, according to the LADWP update. “As pressure builds, crews will again perform targeted leak checks to confirm every section of pipe, both new and existing, is stable and performing as expected.”
Once leak checks are complete, water quality crews will disinfect the repaired section with chlorine, followed by comprehensive water quality testing. Then the water will be dechlorinated and sent into storm drains.
“Only then can crews begin the final steps: backfilling the excavated trench and restoring the street using City of West Hollywood approved materials and paving methods,” the LADWP stated.
A stretch of Sunset Boulevard will remain closed until the sinkhole created by the leak can be filled in.
Sunset Boulevard remains closed between Sherbourne Drive and San Vicente Boulevard, with limited local access on nearby streets including Cynthia and San Vicente.
There is no set completion date, but the DWP said crews “remain dedicated to finishing the repairs as quickly and safely as possible.”
The DWP is working with the Metropolitan Water District of Southern California, Los Angeles County Public Works and other utilities to protect underground infrastructure during the repairs.
The utility said customers in the area continue to have reliable drinking water, but are being asked to continue conservation practices because the area is receiving water through an 8-inch pipe.
Some businesses in the area remain closed, including Book Soup, and many residents suffered property damage in the disaster.
The route for Sunday’s CicLAvia closed-streets event was shortened through West Hollywood due to the water main break. The western end of the 6.1-mile free event, set for 9 a.m. to 4 p.m., was shifted to North La Cienega Boulevard at Santa Monica Boulevard. The route continued east through Hollywood to North La Brea Avenue.
Customers with questions regarding the pipe rupture may call 1-800-DIAL-DWP. Claims information is available at LADWP.com/Claims.
The city of West Hollywood also launched a website with regularly updated information about the response and recovery effort. The site, weho.org/watermainbreak, includes repair updates, street closures, traffic information, Metro detours, parking enforcement changes, claims information, hotel discounts for affected residents and other resources.
Officials said the 10-mile Sunset Trunk Line that ruptured had already been designated for replacement. The department said design work is underway on a project to replace nearly 6.4 miles of large-diameter pipeline and 3.5 miles of distribution pipe, with construction expected to begin in 2031.
The utility said it replaced more than 246,000 feet of water pipeline during 2024 and 2025 and is on track to replace another 246,000 feet this year. The department also said its leak rate is 36% below the national average, averaging 16.1 leaks per 100 miles of pipe compared with 25 leaks per 100 miles nationwide.
The specific cause of Thursday’s break was under investigation, but Anselmo G. Collins, the DWP’s chief operating officer and senior assistant general manager of the water system, said pressure in water delivery lines is highest at night when demand drops.