My current main ground is improperly connected to the water line in my house and I am planning on changing it this week. It is "connected" to (read: formerly soldered, now kind-of-sort-of laying on) a random point on the supply line in the center of my house directly under the bathroom approximately 20 feet from the point at which the main water supply comes into the house.
About 3 feet next to the service panel is what I am convinced is the old water supply when steel was the norm. Instead of running a new grounding wire ~65 feet to the current main, can I run the grounding wire to the steel pipe right next to the box? I do not know any specifics about the pipe other than it being steel but I find it hard to believe that it would have been removed when they converted to copper (my house is ~150 feet from the street).
Best Answer
You would be advised to not depend on the condition of some old discontinued water pipe for grounding. That pipe may have rusted and corroded so much that a lot of it is missing or not even making a low resistance connection into the earth.
If it was me looking to correct this condition I would contact my local building / electrical safety agency and/or inspectors and determine if you can ground with a copper clad steel grounding rod that you would pound 8 or 10 feet into the ground outside the foundation near the electrical service box. Then the appropriate size heavy gauge copper wire would be run from the service panel to the ground rod.