Abandoned Line

A buried utility no longer in service and usually no longer maintained on any map. Abandoned lines are one of the hardest categories to locate because they carry no current, often have no accessible connection point, and belong to nobody who will come mark them.

Abandoned line turns up constantly on older campuses, industrial sites, and redeveloped parcels — a decommissioned steam run, a replaced water service left in the ground, a cut fibre duct. An electromagnetic locator can sometimes still trace a metallic abandoned line if a signal can be induced onto it or applied at an exposed end, but a de-energized, disconnected, or non-metallic run may only show up on GPR, and sometimes not at all. Abandoned lines matter more than their disused status suggests: a crew that strikes one does not know it is abandoned until after the fact.