Thank you for your question regarding pipe grounding. It is our pleasure to help.
The National Electrical Code (NEC) allows the use of water pipes as a secondary grounding electrode given the following conditions:
- You have another grounding electrode, such as a 10-ft driven ground rod in addition to the pipe
- The pipe is bare metal and in direct contact with the earth for at least 10 ft, preferably 20-ft.
- The grounding connection to the pipe be within 5-ft of where the pipe enters the building and before any valves that may impede current flow.
If you should have any further question, please do not hesitate to contact us again in the future.
The Engineering Team at E&S Grounding Solutions
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