Mike Dolt Enterprises
Mike Dolt Enterprises
User: Ranger86, Location: Las Vegas, NV
Asked on: Wednesday, April 20, 2011 at 5:11 pm EDT
Answered on: Tuesday, May 14, 2024 at 4:27 am EDT
Question: I have a pump house, the water supply and the discharge pipes are above ground. The water tank is up on a hill (this is on the supply side).The discharge water line is bonded to the main ground bar. The bond point is where it exits the building.Does the water supply pipe need to be bonded also at the point where it enters the building or is it considered bonded already through all of the nuts and bolts that hold together the piping system?I figured it's a good practice to bond it directly to the main ground bar too since lightning may hit the tank and travel down to the pump house. But is it required?Thanks for your input.
NEC Requirements
According to the National Electrical Code (NEC), metallic piping systems entering or leaving a building shall be bonded to the grounding electrode system by an approved means.
Consideration for Water Supply Pipe
The NEC does not specifically mention whether the water supply pipe needs to be bonded at the point of entry to the building if it is already part of a bonded piping system. However, it is generally recommended as a good practice.
Reasons for Bonding the Water Supply Pipe Lightning Protection
Lightning can travel through the water tank and down the water supply pipe, potentially creating a ground fault. Bonding the pipe directly to the main ground bar provides a low-resistance path for lightning current to flow to the grounding electrode system.
Electrical Continuity
Bonding the water supply pipe ensures electrical continuity throughout the entire piping system. This helps prevent any potential electrical hazards or ground loops.*
Code Compliance
The NEC requires that all metallic piping systems entering or leaving a building be bonded. While the water supply pipe may already be considered bonded through the rest of the system, it is prudent to bond it directly to the main ground bar to ensure compliance.
Conclusion
Although it is not explicitly required by the NEC, bonding the water supply pipe to the main ground bar at the point of entry to the building is recommended as a good practice for lightning protection, electrical continuity, and code compliance. Flag for review