Calling 811 and verifying utility marks is the first step before digging. But experienced crews know that not every line is easy to locate.
Sometimes marks stop short. Sometimes tracer wire is damaged. Sometimes there is an abandoned or difficult-to-locate line that does not match what crews see in the field.
That is why many crews perform a Safety Sweep before they dig—a quick scan with Pipehorn to help identify unmarked, damaged, or difficult-to-locate utilities before excavation begins.