SAN DIEGO - Commuters on Interstate 15 will have some company in between rush hour commutes.
Caltrans is studying the durability and performance of its Barrier-Transfer Machines, also known as "zippers."
Each BTM moves concrete dividers that separate the Express Lanes one lane over. During April, two BTMs will move the barriers two lanes over, giving three lanes in the direction of the rush hour commute.
Express Lane drivers will have the benefit of having three lanes instead of two. Drivers going the other direction will be limited to only one Express Lane.
"It gives motorists more flexibility," said Caltrans spokeswoman Cathryn Bruce-Johnson.
Caltrans is only studying the machines, not the impact of the extra lane on traffic. SANDAG, which manages the Express Lanes, did not respond to 10News inquiries about whether the BTMs would be used on a regular basis.
BTMs are regularly used on the Coronado Bay Bridge to add a lane for the rush hour commutes.
The Express Lane trek takes each BTM about two hours to move the 16-mile center divide.