While the utility repairs a broken underground valve, customers remain on a boil water alert and are being urged not to use their running tap water if it happens to be working.
"Wait until we give you the go-ahead -- but if you have to use water use as little as possible, " said Janisse Quinones, CEO and chief engineer of the LADWP.
The affected area is bounded roughly by Rinaldi Avenue on the south, Balboa Boulevard on the east, De Soto Avenue on the west and the foothills and hills to the north, according to the DWP.
According to the agency, water crews were conducting repair work on Tuesday at a pump station that connects to a 10 million-gallon water tank that serves the area when a valve that controls the flow of water failed to open.
"As a result, the water flowing from the tank into the pipes serving the area was cut off," according to a DWP statement.
Crews immediately embarked on repair efforts, digging to reach the valve that is located about 20 feet underground.
DWP officials originally said the repairs could take until Friday, but later said the project could "take through this weekend to be completed." The utility noted that accessing the broken valve has proven problematic because its location also has two underground oil pipelines, a fiber optic line, gas line and large boulders that "have complicated repair efforts."
DWP officials said they were working on a possible temporary fix that would involve pumping water from a nearby Metropolitan Water District of Southern California facility into the DWP's 54-inch trunkline that feeds water to the affected area.
It was unclear when or if that temporary fix might be implemented.
The DWP established water distribution sites providing drinking water to affected residents from 7 a.m. to 9 p.m at:
-- Holleigh Bernson Memorial Park, 20500 Sesnon Blvd., Northridge;
-- O'Melveny Park, 17300 Sesnon Blvd., Granada Hills; and
-- the intersection of Tampa Avenue and Sesnon Boulevard on the Northridge-Porter Ranch border.
Thousands of LADWP customers remain without service amid water outage in Granada Hills, Porter Ranch
On Friday, the DWP opened an additional distribution site operating from 5 a.m. to 10 p.m. at the Porter Ranch YMCA, 11336 Corbin St.
LADWP is also providing customers with non-drinking recycled water, portable showers, hand-washing stations, mobile laundry units, and portable toilets. The services are being offered at the water-distribution sites.
For the latest updates, visit www.ladwpnews.com.
City News Service contributed to this report.