Old Copper Water Supply as Grounding Rod for Residence

[jbroberts38]

Hi,
I have older Residential system that is grounded to a 1" copper water line (in addition to the Neutral Service wire) Obviosly before "Bonding". Line passes through about 20' of clay, 2 feet below surface. Copper line no longer connects to water main, so is it essentially a large grounding rod run horizontally. Water table is such that the clay is at least moist if not wet. Has been in place for 50 years now.

Since it is now disconnected from the county water supply, is it providing enough of a ground for a residence? If not, I presume I need to add new thicker grounding rods 10 feet apart, etc?

While we have a transformer on the supply pole we are connected to, there does not appear to be a separate copper ground wire down the pole.

Obviously, installing two ground rods through 10' of clay to build new ground system is no small job. Possible, but royal pain.

Is the old copper water pipe going to handle a lightning strike to the transformer/pole area?

Please advise. Thanks!

[WyrTwister]

If in doubt , install a ground rod .

God bless
Wyr

[cgostola]

While your cold water bond is a sufficient source of ground, NEC 250.53 A 2 requires a supplemental grounding electrode. Hence you need to install a ground rod or other electrode permitted by the NEC article stated above. A ground plate may better suit your needs than a rod electode

[jtrammel]

I use my hitachi hamerdrill to drive ground rods, it makes light work of it.

[bourbon]

X2 to jtrammel. You can actually buy ground rod driver adapters to chuck in a hammer drill, but they are a little pricey if you only have one or two to do.