Cal. Vehicle Code § 35580

(a) The Legislature finds and declares that a substantial number of container trailers using California highways exceed weight limitations authorized for California highways. Intermodal container trailers are containers which have been unloaded from ships or trains and placed on truck chassis, or are piggyback trailers unloaded from trains, for subsequent transport upon the highways. Container trailers are usually loaded by shippers in other states or foreign countries where gross and axle weight restrictions imposed by this code are of no concern to the loader. These loading practices often result in overweight vehicles traveling on California highways, which contributes to highway deterioration. (b) The Legislature further finds and declares that the continued growth of intermodal transportation within the United States and the Pacific Rim makes it important for California to initiate a program to allow intermodal freight to be weighed at major terminal locations prior to operation on the highways, to ensure that these vehicles are within the established weight limits. The Legislature finds that the imposition of heavy fines and assessments is one means of reducing the number of overweight vehicles on the highways. A more effective, and preferable, alternative is to assure that intermodal container trailers are properly loaded at the outset by the party responsible for loading goods into the container trailer, so that vehicles meet weight requirements prior to their operation on the highways.