[Nebraska2#]

Hi all. Daughter's newish house. They are looking to add on to the house. I spent sometime today looking at different things pertaining to that. Hvac, plumbing, electrical, etc. I have another electrical question. Picture shows a # 10 or 12 wire attached to a clamp, attached to cold water pipe. Wire runs outside and is attached similarly to a steel rod in the ground. Water pipe supplies washer. I haven't located any other grounding or bonding inside or outside the house.
Garage is powered from house service. The service box there has a large wire running to a copper rod outside the garage. Thoughts?

 

[surferdude2]

It is probably a supplemental ground that some inspector required as a result of there perhaps being a plastic water line serving the building.

The wire is too small to be the Ground Electrode Conductor for the service panel. That's likely happening somewhere else.

Leave it in place.

 

[Nebraska2#]

Thanks for replying. Incoming water supply is steel. I couldn't find any other ground connectors at the house.

 

[surferdude2]

The Ground Electrode Conductor origins aren't always in view but you should be able to see where it terminates in the service panel at the grounding bar terminal strip or lug. It will be #8 or larger.

An inspector can refuse to accept older steel water pipe as a required ground and may request another method such as what you are seeing with that ground rod.

 

[surferdude2]

Update: From your other thread with the picture of your main panel, it's clear that you have a 200 panel so the Ground Electrode Conductor will be required to be #4 copper or #2 aluminum. You will have to remove the front panel to see it.