On December 9, 2021, in Cargo Messaging Service (CSMS) #50336522, U.S. Customs and Border Protection (CBP) issued updated emergency protocols issued jointly with Canada Border Services Agency (CBSA) to address the flood situation in British Columbia, Canada. According to the guidance, Canadian domestic truck carriers may need to transit through the U.S. to reach destinations in Canada. “Any Canadian carriers that currently operate between the U.S. and Canada as well as domestically are expected to follow the standard procedures for transit, including the advance filing of an electronic truck manifest and utilization of an in-bond or in-transit transaction. This applies to both rail and truck carriers."
The CSMS provides additional details on travel documents, entry filing, and container security. It also provides product specific guidance and instructions for carriers who are unable to file electronic manifests.
CSMS #50336522 can be found here:
Guidance was previously issued in CSMS #50162293: