3rd GEC

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SAP

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Fresno Ca
On a service change if I have a existing underground metal water pipe GEC # 6 ,I supplement the water pipe with a ground rod,I drive my ground rod right next to my water pipe.I bond rod to water,my MSP is on the other side of the house,do I need to put a another ground rod even though I have two GEC water and the ground rod I just drove in,I'm asking cause it seems like every AHJ wants a 2nd Ground rod,9 times out of 10 where the MSP is it is concrete I have to roto hammer the concrete get it has close to the wall has possible,9 Times out of 10 I hit over spell of the foundation.I don't think anybody likes driving ground rods,Is the code supplement underground water pipe with another Grounding electrode only one ground rod Done! I can't find anything 250.53(D) that tells me I have to make sure that that supplemental ground rod has 25 ohms are less I'm I missing something
 
Sorry

Sorry

MSP is not in concrete was typing to fast.I ment on the side of the house with a concrete side walk leading to back yard
 
SAP said:
...do I need to put a another ground rod even though I have two GEC water and the ground rod I just drove in,I'm asking cause it seems like every AHJ wants a 2nd Ground rod,I can't find anything 250.53(D) that tells me I have to make sure that that supplemental ground rod has 25 ohms are less I'm I missing something
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Punctuation, spacing, and hitting Enter a couple of times to break up the lines of text will help make your post easier to understand.

The inspectors making you drive a second rod are correct. Any time you have a water pipe in your Grounding Electrode System you are required to supplement it. Usually two ground rods are the easiest way.

250.53(D) tells you a water pipe needs to be supplemented according to 250.53(A). 250.53(A)(2) tells you that a single ground rod has to be supplemented by any of the electrodes listed in 250.52(A)(2) through (A)(8). Notice that water pipe is excluded.

The 25 Ohm thing is an exception in 250.53(A)(2). Its easier to drive the second rod that to prove your single rod meets the exception.
 
I found it ,if the supplemental electrode is of rod,pipe or plate type,it shall comply with 250.53(A),from what I'm reading we have to supplement the water then supplement the ground rod with another supplemental grounding electrode
 
Thank you, You explained it well. I got to work on my writing skills, I try to explain into to much detail and it starts to get all over the place, Will work on that
 
SAP said:
I found it ,if the supplemental electrode is of rod,pipe or plate type,it shall comply with 250.53(A),from what I'm reading we have to supplement the water then supplement the ground rod with another supplemental grounding electrode
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Yes, and just to make your life easier, if there is already a GEC running from one rod back to the panel you can just use a bonding jumper to connect the second rod (6 feet or more away) to the first rod and so make use of its GEC.
There is no code requirement for the second rod to be close to the panel.
 
SAP said:
I found it ,if the supplemental electrode is of rod,pipe or plate type,it shall comply with 250.53(A),from what I'm reading we have to supplement the water then supplement the ground rod with another supplemental grounding electrode
Click to expand...

The water pipe needs to be supplemented by another electrode. A single rod is not an electrode unless it can be proven that it has a resistance of 25Ω or less so two rods are typically used to make up the supplementary electrode. When using two rods as an electrode you do not need to meet the 25Ω resistance requirement of a single rod electrode.
 
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