This stuff is always enforceable in North America. The CVSA regulations are always in effect & thou shalt not lose thy particulate load! A quick call to either the usual local law enforcement may or may not resolve the issue. The person that answers the call may not have a clue about enforceable load security laws. However, the smarter choice will, like as not, be to call the Provincial / State commercial vehicle enforcement agency. Now THOSE guys know! They will quote chapter & verse as to exactly what can & cannot happen for a commercial carrier to operate on a gazetted road.
As law enforcement, I have dealt w/ these issues many times. In the pre-smart phone / dash cam era, we required the complaianant to provide a statement 1st. Once done, the carrier could be charged (if the jurisdiction allowed for the prosecution of the RO) or the carrier might just designate the driver to the investigating agency. Either way, if the offending party plead not guilty, the onus was on the complainant to secure a conviction on their evidence in court. We really didn't have a lot to do w/ it at trial. A few times, the carrier was called, informed of the issue & they asked if they could deal w/ the complainant directly. Once this was confirmed, the issue would go away.
When a complainant is told something to the effect that, "We can't work w/ that here," read that to mean something like, "We just don't care & are too busy."
My two pennies.
John.