Excavation crew contacts underground power lines
An excavation crew was installing anchors for a shoring
system to support a water main close to an excavation. The
prime contractor and shoring contractor relied on "as
built" drawings and visual reference points to decide
that an underground electrical duct bank was far enough
away from the water main to pose no hazard. Workers were
using an air track drill when two anchors severed power
lines inside the duct bank and caused a power failure. The
drilling crew was unaware of the contact when it happened.
Fortunately, there were no injuries.
The "as built" drawings were inaccurate in terms
of the depth of the electrical duct bank and its distance
from the water main. The drawings included a disclaimer
that the owner of the utility took no responsibility for
accuracy of the information.
This is not an isolated incident. In several recent incidents, excavation equipment has contacted underground services.
Safe work practices:
- Accurately locate underground utility services before excavating or drilling with power tools.
- Ensure that excavation work is carried out in accordance with the requirements of the utility owner.
- Provide written safe work procedures when working in proximity to underground utility services and ensure that
workers follow these procedures.
