The 4-mile stretch will allow solo drivers who previously did not qualify to use the carpool lane to use the now-classified express lanes for a fee, officials said.
The toll for solo riders to use the roads will range from 30 cents to $6, with the average toll at $3, according to transportation officials. The toll price will be based on road congestion.
Vehicles with at least two occupants will continue to use the express lanes at no charge.
The express lanes will operate during the same hours as carpool lanes, with an exception of an extended hour in the morning only on westbound Highway 237.
The hours of operation are 5 a.m. to 9 p.m. and 3 p.m. to 7 p.m. during the evening commute.
Because of inclement weather last week, the opening of the express lanes was postponed from March 15 to 5 a.m. this morning.
The opening is scheduled to take place at 430 McCarthy Center at North McCarthy Boulevard and Ranch Drive at 5 a.m.