The closure, which begins Tuesday, is expected to disrupt traffic flow in neighborhoods near the freeway which already see heavy congestion during peak commuting hours.
The closure will affect two sections of the road: From the 405 to Bellagio Road and between Beverly Glen Boulevard and Carolwood Drive.
Officials will keep one lane open in each direction to allow for some traffic flow. The other lanes will be closed between 9 a.m. and 3:30 p.m. during the week and 8 a.m. to 6 p.m. on Saturdays.
Los Angeles City Councilman Paul Koretz said commuters are advised to take alternate routes to Sunset.
He is hoping that if drivers stay away, it will be similar to the "Carmageddon" shutdown of the 405 Freeway for a weekend in 2011, when instead of creating a traffic nightmare, many drivers simply stayed off the roads during the closure.
"This is just like Carmageddon on the 405," Koretz said. "It could have been backed up for miles, but because everybody stayed away and worked with us, it wasn't a big deal. We're hoping the same thing will be true here."
Crews will be installing new underground circuits to help improve electrical capacity and reliability in Bel Air, Beverly Crest, Westwood and Holmby Hills.
Some of the systems in those areas are now operating at 120% of their capacity, according to the Los Angeles Department of Water and Power.
More information about the DWP project is available here.