Learning from Incidents: Low Voltage Cable Damage

    Learning from Incidents: Low Voltage Cable Damage


  • An unprotected low voltage (LV) cable became unearthed and damaged during grading works to an embankment at Grantham North Feeder Station as part of the East Coast Mainline Power Supply Upgrade (ECML PSU) project. As a result, the LV power to the feeder station was disrupted.
  • Prior to the works commencing, the working area was scanned with a CAT4+ scanner which did not detect any cables.


  • Legacy buried service information was referred to in the task briefing documentation. It did not highlight any buried services and the team assumed this allowed for mechanical excavation.
  • The Site Supervisor had not undergone a formal assessment to be deemed competent to issue a Permit to Break Ground.
  • The LV cable was installed by 3rd parties and not physically protected by ducting, sand or warning tape.
  • The Signal Generator (Genny) was not used when surveying the area. Some cables do not radiate detectable power or radio signals and therefore a Genny must be used every time prior to breaking ground.
  • Those responsible for the safe completion of the planned works did not challenge the working methodology, despite having a clear understanding of the risks associated with mechanically excavating near to electrical assets.


  • Buried service information to be reviewed by those planning and managing the works and all legacy information removed.
  • In addition to buried services information, the ground should always be CAT and Genny scanned.
  • Permit issuers should be competent in the relevant procedures.
  • All users of Cable Avoidance Tools should be trained and use these in accordance with the Manufacturer’s instructions.



Acknowledgement Slip

First Name
Email Address
Company Division
Do You Have Any Questions? *