What's involved in going underground
Before a project begins, opportunities to do the work with other utilities are investigated. Next, permits and consent must be obtained. Discussions with residents also take place regarding where transformers and switchgear will be placed.
Then the actual route is planned. This involves designing the layout of the new underground network, as well as determining the size of the cables and locations for the transformers, switchgear, streetlights and in-ground service pits.
We locate all existing underground services along the route to ensure they are not disturbed by the work. This is usually done by marking the locations with coloured paint.
Keeping everyone informed
Then the actual route is planned. This involves designing the layout of the new underground network, as well as determining the size of the cables and locations for the transformers, switchgear, streetlights and in-ground service pits.
We locate all existing underground services along the route to ensure they are not disturbed by the work. This is usually done by marking the locations with coloured paint.
Keeping everyone informed
Residents, businesses and schools along the route are notified by letter that their area has been selected. Other organisations such as emergency services, taxi and bus companies are also advised. This ensures everyone is aware that there may be disruptions in the area so they can arrange alternative parking or use other routes.
When work is about to start, signage goes up along the route. The signs help alert drivers that traffic may be affected.
Large projects also have the services of a Vector project ambassador on site at all times to help with any questions or problems residents or anyone else may have even if it is to ensure your driveway is clear. And, on all underground projects, you can call 0800 GO UNDERGROUND with any questions about the project at any time of the day.
When work is about to start, signage goes up along the route. The signs help alert drivers that traffic may be affected.
Large projects also have the services of a Vector project ambassador on site at all times to help with any questions or problems residents or anyone else may have even if it is to ensure your driveway is clear. And, on all underground projects, you can call 0800 GO UNDERGROUND with any questions about the project at any time of the day.
From street to house
When overhead lines in the street go underground, it is also necessary for each property's service line to the house to go underground too. Vector offers to do this work for the residents for free. Customers are visited by one of our project team members to discuss the best route across their property for the new service cable and connection details. Once agreed this is recorded on a form which customers and Vector retains copies.
When overhead lines in the street go underground, it is also necessary for each property's service line to the house to go underground too. Vector offers to do this work for the residents for free. Customers are visited by one of our project team members to discuss the best route across their property for the new service cable and connection details. Once agreed this is recorded on a form which customers and Vector retains copies.
Now let the work begin
Now that preparations are complete, work can begin in the street. This is usually carried out in 50 to 100 metre sections and it generally takes around one month to complete each section. Work is carried out in a number of different sections at the same time in order to complete the project as quickly as possible.
Here's what is involved in each section of work:
Now that preparations are complete, work can begin in the street. This is usually carried out in 50 to 100 metre sections and it generally takes around one month to complete each section. Work is carried out in a number of different sections at the same time in order to complete the project as quickly as possible.
Here's what is involved in each section of work:
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The new underground power network is installed along the streets under the grass berm or footpath, either in a small trench or through ducts installed by drilling, which doesn't disturb the footpath. If the area is rocky it is unsuitable for drilling so we will need to open trenches.
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Where street cables need to cross the road, these too are installed in either a small trench or by drilling.
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New underground service connection pits are then installed, usually one for every two houses. Underground cables are then installed to each house. Where possible, drilling will be used.
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Work on service connections requires a power shutdown when we transfer a customer's power supply from their old overhead line to their new underground cable. We negotiate an appropriate time to do this with the house or business owner.
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The overhead lines cannot be removed until we've transferred all the customers to the new underground network. New streetlights must also be installed because the exisiting streetlighting is usually mounted on our power poles.
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The power poles and overhead lines are removed and the footpaths and grass berm areas are then reinstated. This reinstatement work is done as quickly as practical once excavation work has finished.
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A full audit of the work is carried out to ensure that it has been completed to a high standard. As work is completed, a survey is distributed to all those along the route to gather feedback, so we can improve our service on future projects and resovve any outstanding issues.
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Finally, the signage is taken away. The project is complete.
As you can see, there is a lot more than meets the eye when it comes to undergrounding. But, it's certainly a most worthwhile undertaking.
