How can I find where the power lines are under my garden?

[dominoman]

I would like to redo my overgrown garden and put in a new path, patio and some lighting. It will involve a mini digger as it needs some leveling and digging.

I currently have an old garage at the end of my garden that has power going to it. Is there any instrument that could find where the power lines go across the garden so I don't accidentally dig them up?

It might also save me some money if I can tap into the existing power line for my garden lights.

 

[Iggifer]

Not reliably. The best way is to find either end of the cable by hand, and then extrapolate the route from that, allowing for a bit of deviation from straight (maybe dig a hole in between the two points to confirm)

It should be reasonably deep, so I guess it depends how deep you are planning on digging?

As to whether the existing cable is suitable to take a lighting feed from depends on the current set up. but it's unlikely to be of much use to you

 

[RF Lighting]

You could hire a cat scanner and tone generator.

 

[endecotp]

http://www.hss.com/hire/c/surveying-and-location/locators

But if you know where the ends are, it may be easy enough to hand-dig a hole half way along and locate it there, then repeat as necessary until you have a good enough idea of the location.

 

[securespark]

You could hire a cat scanner

 

[flameport]

If a mini digger will be used, you should hire the scan tool anyway, as there may be other things concealed underground. While gas, water and electricity supplies should be buried at a certain depth, there is no guarantee of that.

 

[westie101]

Do not under any circumstances just hire a CAT (cable avoidance tool), you must also hire a matching signal Generator (GENNY).
And get some training on how to use it
The CAT will only positively locate cables that are live & are carrying a reasonable bit of load (usually in the 20 - 30A range as a minimum).
Research also where your supply cable (talk to your DNO), BT line and the like are

 

[dominoman]

Ah OK. Sounds like it isn't as easy as I thought.

I think I'd be better off just killing the power while I work and trying to avoid the area where i think the cable is.

I'm generally adding earth rather than removing so hopefully it will be OK.

 

[Iggifer]

You can kill your local power, but if as Westie says, the supply cable comes through your garden, you can't turn that off.

The DNO should have records though, as should BT, VM etc. A quick call (or 5) should be enough to get the answers

 

[endecotp]

trying to avoid the area where i think the cable is.

Yeah, that's going to be massively more successful than anything suggested above... Not!

 

[bernardgreen]

The DNO should have records though,

Gas man digging a trench near here yesterday knew there were LV ( 230 V ) and HV ( 11 kV ) cables under the grass verge, about 18 inches apart according to the charts. He found them side by side along with a third cable.