The Los Angeles Department of Water and Power has completed a $130 million, 11.4-mile underground transmission cable as part of the public power utility’s ongoing plan to replace aging infrastructure.
The 230-kilovolt Scattergood-Olympic Cable A transmission line — the longest underground transmission line in LADWP’s power system — will improve system reliability in western Los Angeles while bolstering the system’s flexibility, LADWP said.
The new line, more than six inches in diameter and weighing 35 pounds per foot, replaces a line that started operating in 1974 and was experiencing reliability issues, according to LADWP. The old line will be used a backup, providing redundancy in case the utility needs to use it during an emergency.
LADWP said the new line will help it more efficiently use its generating resources, including its 716-megawatt Scattergood power plant in West Los Angeles. The natural gas-fired power plant is at one end of the transmission line. (E.F. Scattergood played a key role in the development of public power in Los Angeles and designed the 267-kV line connecting the Hoover Dam to the city).
“The Scattergood-Olympic Transmission Line increases our ability to provide safe and reliable power 24/7/365,” said Reiko Kerr, LADWP senior assistant general manager of the power system. “This project and other transmission line upgrades are critical parts of transforming LA’s power supply and rebuilding our aging power grid infrastructure so that we can effectively deliver increasing amounts of renewable power to our valued customers.”
The transmission cable is connected through underground vaults that are less than half a mile apart, which reduced the project’s cost and will improve reliability, according to LADWP.
The project took about a decade to complete, with about five years spent on the approval process and five years building the line.
The project underwent a complex permitting process. The transmission line, for example, goes through the Lincoln Boulevard Bridge over Ballona Creek. Caltrans, the state’s transportation department, required safety studies before construction on the bridge could occur.
Other agencies and organizations involved in the project included the Federal Aviation Administration, the California Coastal Commission, the Los Angeles Department of Transportation, the Los Angeles Bureau of Engineering, the Los Angeles Council District 11, five neighborhood councils and the city of Culver City.
The transmission line project is part of LADWP’s power infrastructure plan, which was initiated in the mid-2000s when stretches of high temperatures caused power outages in L.A. Since the effort started, LADWP has seen a 20 percent drop in power outages, according to the utility.
In 2014, LADWP expanded the program, which had focused on distribution assets, to include generation, transmission and substation equipment.
As part of the effort, LADWP intends to replace up to 30 circuit miles of 138-kV low pressure oil-filled cable a year.
Along with his role in the development of public power in Los Angeles, E.F. Scattergood also played a role in the creation of the American Public Power Association.
The Association’s most prestigious award is named after Scattergood and recognizes a community-owned utility that has enhanced the prestige of the Association and of public power through outstanding service to customers.