Recently I discovered 3/4 and 1/2 inch copper pipe, pin-hole leaks in 6 places. All have been repaired with copper. I have heard several voodoo-type explanations for these leaks and I have sent a pipe sample to the manufacturer for analysis. Water enters the house from a 105-foot deep well through the concrete basement wall in black plastic pipe. Just inside the house it passes through a 1-1/4" galvanized hose barb, 1-1/4" brass valve, 1-1/4" galvanized nipple, 1-1/4" elbow, and a 1-1/4" x 1" galvanized reducer into copper. I think the plumbing was installed during construction in about 1998. Can improper pipe-grounding result in pin-hole-sized leaks in copper? What is the best way to properly ground copper pipe and prevent further leaks?

 

Usually copper pipe isn't "grounded" with wire.
Usually the main service is copper and that grounds the copper plumbing.
PEX and other non-metallic connections can affect that.

There would normally be a connection from the water service where it enters the house to the electrical panel.

I think most pinhole leaks are cause by high mineral content.

 

I agree that pinhole leaks are usually caused by the water, not the electrical system. Usually having to do with low (or high?) pH.

The grounding (or bonding) to your electrical system is still a good idea from a safety perspective. You should have a large gauge wire from the copper piping (check near the pressure tank or near the water heater) to your electrical panel.

An electrical system installed in 1998 will most likely have a proper bond to the plumbing system.