Why is it important to check for underground cables before excavating?

Ground CrewIt is important you know where underground power cables are located before undertaking any excavation work for your safety and those of others around you.

If power cables are struck it could result in an electric shock, explosion and the loss of power. It is the legal responsibility of the person intending to excavate, that they determine whether or not there are any services in the vicinity before commencing work.Location Finding

Does Northpower offer a cable location service?

Northpower will provide information on the location of its underground power cables in public roads/footpaths by providing copies of plans where possible, or by marking on site using cable location equipment and red or orange spray paint. In some instances there may be cables on private property also. For more information or to book a cable location please refer to our Safe Digging page.

How much does the cable location service cost?

If adequate notice is given of at least two working days, this service is currently free during normal working hours (7.30 a.m. to 4.00 p.m. weekdays). Any on site supervision which we may deem necessary to avoid damage to our installation, is also free during our normal working hours. Charges will be made for services provided outside these times, and we reserve the right to charge if less than two working days notice is given. A small fee may be charged to locate service cables on private property.

What are the rules when excavating on site?

It must not be assumed that information provided by plan or marked on site is absolutely accurate. For example, cable locators are not exact, building lines or curb lines (from which measurements were taken at cable installation time) may have shifted, and depths may have changed due to road/footpath reconstruction. For this reason, and to ensure your safety, we advise that mechanical digging aids must not be used within 450mm of a power cable. Where the location of cables is not certain, hand digging to locate them must take place before mechanical diggers are used, in order to comply with the 450mm clearance. Power cables may be buried with timber, concrete or plastic slabs above for mechanical protection, or inside ducts. Installations may also have an orange plastic danger tape indicating electrical cables below. Any mechanical protection or warning tape which is disturbed by excavation must be replaced in its original position.

Location FindingWhilst reasonably robust, electrical cables should be treated carefully. They must not be moved without Northpower approval. Some rely on paper for insulation, and any kinking can result in electrical breakdown with the risk of explosion. Please note that we retain the right under OSH Legislation to prevent any work continuing, that is likely to cause damage to any Northpower installation, or is likely to cause serious harm to any person.

Repairs can be expensive and costs are chargeable. Nevertheless, it is absolutely essential that any damage or suspected damage to a power cable is reported immediately.

Northpower uses the Department of Labour’s Guide for Safety with Underground Services to develop its policy for the location of underground cables. This booklet is available from the Department of Labour for $10.00.

For more information or to book a cable location refer to our Safe Digging page