What is the true reason of earthing (domestic) water pipes?

Question

I have seen houses where the water mains was used as the source of obtaining a "good earth" to ground everything else within the house, including the fuse box and the "green wire".
Another time I was told that water pipes are earthed to avoid a harmful potential to occur on any on the water taps.
Now I see a house which has a rubber hose coming from the well and pressure tank, and copper pipes only start to be used after the softener tank. Still, the fuse box and the telephone cable are religiously connected to one of those copper pipes.
Who is earthing whom? A water filled rubber hose can't be a "good earth".....?

Answer 1

This practice has been banned in the electrical codes of most
areas. It was as you were told originally, a method of grounding the fuse box. I have worked on the plumbing in old houses and can tell you that it is not a good idea. When current runs to ground through a water pipe and you are working on that water pipe it can be most unpleasant. In the case where the supply is via a rubber hose it must have been done before the supply was rubber, the pipes might go to ground at some point or the person who wired it didn't really know why they were doing it. At any rate, you should not see this in newer homes that were wired by a knowledgeable electrician.

MP

Answer 2

In the past the cold water line was used as a grounding system. In the past water systems always had metal pipes so this worked just fine.

Now more and more houses have all plastic pipes and old houses that had metal pipes are being retrofitted with plastic fittings.

The best way to ground an electrical system today is to drive two copper ground rods about 6' apart and connect the ground wire to those.

Some places still require a cold water bond though ground rods are also required.

Answer 3

I'm not an electrician, but I think that a good ground is required to prevent electrical shocks to the occupants. Electricity will take the easiest path every time, so a good ground is necessary for that. If it's not done using the pipes, it could be done at least 2 other ways. One might be to ground everything to the breaker panel, which is connected to the ground wire coming in from the street. Another would be to drive a steel spike into the ground, and connect the wiring system's ground wire to that.

Again, I'm not an electrician, so before you decide to rewire your house, check with an expert!

Answer 4

The house used to be earthed to the ground via the copper water pipe supply because copper is one of the greatest conductors of electricity. The main water supply has a current running through it to help prevent corrosion of the mains water supply pipes. Any copper pipe that is embedded in the earth for the term of its life is going to a great earthing choice. anyone who says that rubber is going to do the job, doesn't know what their on about. A copper stake near the fuse box is now the norm. Demarcation and ease of acsess are the reasons.

Answer 5

Installing water lines and drainage line above ground, (on some height to avoid hurdles in everyday movements of men and transport - everyday life) will require much more infrastructure facilities. For drain lines one will need to pump their sewage in the line, which will require large number of pumps and very large quantity of power. This is one of the main reason for grounding the water and sewage lines.

Answer 6

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