How do I report debris on a freeway in California?

If it's affecting traffic or is an actual hazard, call 9-1-1 and inform the dispatcher of its rough location and what the item or items are. They'll send a cruiser by to inspect it and the ChiP officer will likely halt traffic to remove it.

If it's just items in the roadway, that are not causing an emergency here's the CHiP non-emergency number:1-800-TELL CHP (non-emergency) (1-800-835-5247). They'll direct your call to the correct office and then you can report your issue from there.