A planned 55-hour closure of both sides of the 91 Freeway continued Saturday between Interstate 15 and the 71 Expressway to accommodate construction activity.
The closure of the approximately six-mile stretch of the freeway is set to end at 4 a.m. Monday, according to the Riverside County Transportation Commission.
Media briefings on the closure are scheduled this morning and Sunday morning.
"We had considered performing this work over a series of 20 consecutive night closures, but we know how important it is for Corona commuters to get on the road very early each morning," commission Director Anne Mayer said Wednesday.
"By consolidating this work into one weekend, we are able to create a safer working environment for our crews and the motoring public."
The commission has been promoting its "91 Steer Clear'' campaign since last month to make drivers aware of the closure and how to prepare.
During the shutdown, all westbound traffic attempting to transit the Riverside Freeway through Corona will be diverted onto Interstate 15, and all eastbound vehicles will be detoured onto the Corona Expressway.
Officials anticipated major backups on Interstate 15 and the Corona Expressway, as well as on surface streets in Riverside and west Corona.
Riverside officials have warned of lengthy travel delays throughout the west end of the city, particularly along La Sierra Avenue and Pierce Street.
Commuters trying to go east or west via inland or Orange County freeways were encouraged to utilize Interstate 10, state Route 60 or state Route 210 through the weekend.
Mayer predicted Interstate 15, the 71 Expressway and Riverside Freeway will be clogged around the closure zone, with delays stretching three to four hours.
CHP officers, Riverside County sheriff's deputies, as well as Riverside and Corona police officers will be out in force for traffic control and to respond to emergencies during the shutdown.
All road work on detour routes in Los Angeles, Orange, Riverside, San Bernardino and San Diego counties will be halted this weekend to spare motorists added delays, according to RCTC.
Metrolink announced it will offer a two-for-one promotion for commuters and will double the number of trains Saturday and Sunday between Riverside, San Bernardino and Los Angeles, providing another travel option for commuters.
The freeway closure will enable crews to tackle three major components of the "91 Project Fast Forward'' without traffic conflicts.
Mayer said that the westbound side of the Maple Street bridge at the 91 will be demolished, and crews will install support beams at the flyover ramp connected to the bridge, as well as pave a portion of the eastbound Riverside Freeway under Interstate 15.
Several mini projects will also take place, such as filling potholes, painting K-rails and patching ramps and bridges along the heavily used corridor.
According to Mayer, the shutdown will not settle all construction needs, noting that future overnight closures will be necessary at various locations in the project area -- though nothing approaching the magnitude of this weekend.
The $1.3 billion 91 expansion project, which began in early 2014, involves widening the east-west corridor between the Orange County line and Interstate 15, with new traffic lanes and ramps, as well as additional shoulder space and enlarged surface streets in the vicinity of the freeway.
More information is available at http://sr91project.info/ or by calling (877) 770-9191.
City News Service contributed to this report.