Chino Hills and Brea have each adopted resolutions requesting Caltrans to ban large truck traffic from using Carbon Canyon Road.
The cities submitted the resolutions to Caltrans June 19.
State Route 142 extends from Chino Hills Parkway in Chino Hills to Valencia Avenue in Brea and is in the jurisdiction of Caltrans 8 and Caltrans 12.
The city has been working for the last few years with Caltrans, the Chino Hills and Brea police departments, the City of Brea, and the California Highway Patrol to study the problem.
It was agreed that a traffic study was needed to identify key issues and propose solutions with an emphasis on banning large-truck traffic.
Residents have been expressing concern that excessively large trucks cannot maneuver through the tight curves along Carbon Canyon Road and encroach onto oncoming traffic as they make the turns.
Chino Hills and Brea shared costs for the traffic study.
Caltrans 8 Deputy District Director of Operations Catalino Pining said his department will expedite the process.
Carbon Canyon resident Erik Simonsen said he is concerned that the extensive road paving project underway on Carbon Canyon Road may not last long on the S-curves because of the wear and tear by the large big rigs and double trailer dirt-hauler trucks.
He said the trucks are especially destructive as they move up and down the narrow S-curves.
“I wish the cities of Chino Hills, Brea, and Caltrans would speed up implementing the new truck rules,” Mr. Simonsen said. “When the S-curves were repaired about three years ago, the area was quickly damaged again by the large trucks.”