Officials are warning drivers to stay away from high-occupancy toll lanes.
The state has been trying to create a network of high-capacity, high-frequency lanes, which would allow drivers to get to and from work and school and access the highway for longer.
Drivers are getting caught in the jam by the high speeds, which have caused hundreds of injuries and caused thousands of miles of damage.
President Donald J. Trump announced that the Highway 101 project will be completed in 2021, but will not be finished until 2024.
The project, a $1.3 billion highway, was originally set to be completed by the end of 2017.
But the Department of Transportation, in partnership with the National Highway Traffic Safety Administration (NHTSA), has now been told to complete the project by July 2021.
The department said it has been in contact with NHTSA and will be providing them with more information as soon as possible.
President Donald Trump signs the proclamation on the construction of a new highway, in Phoenix, Arizona, on March 14, 2021.
Trump has been criticized for not following through on his campaign promises to build a new road to connect Phoenix to Las Vegas, which is expected to cost as much as $1 trillion.
NHTAS has said that building the highway will provide millions of jobs, create tens of thousands of new homes, and increase traffic safety.
The president has said the project is being done with the help of private-sector partners.