I am about to build a large shed in my garden on previously unoccupied ground. I have a niggling feeling though I may be building on top of my mains water supply to my house. Solely because the isolation Toby is in the road immediately adjacent. Assuming a straight line to the isolation Toby in my house then it is right where I want to build. Can I rent some sort of device to map the pipe route? I’m assuming worst case I have a plastic pipe. Can I tap in at the Toby on the road and insert say a length of fencing wire to provide a metal object to follow? What would be the name of the device I need to map the whereabouts of my pipe?

This may help?

http://www.pvcpipedetector.com/buried-pvc-pipe/

Ask your water board to do a track and trace.
They may charge for the section after the stop tap.
If they do just ask for the rack in the street and “meet” their man on site with a brew.

This is what I used

Seriously, electrical cables / metal pipes are relatively easy to detect but plastic pipes are a lot harder. So most people just dig with some care, based on the position of the stopcock and the entry into the house you can guesstimate the path of the pipe in the garden.

I would ask Toby.. 8)

As above rough straightline it. Then dig.

Dig a trench roughly perpendicular to pipe line. One at either extent at you shed perhaps.

Then just build over it anyway if it needs to move at a future date just diconnect and put new pipe in the ground.

MDPE water pipe is pretty hard to trace. Digging and following it is the only sure fire way.

What’s the issue with building over the top? If there’s a problem with it, just abandon it in the ground and lay a new one.