Grounding Electrode need to be Supplemented?

[shortcircuit2]

Dwellings copper town water pipe has just been replaced with plastic from the street so the service needs to be regrounded.

The dwelling has an old 1.25 galvanized pipe extending 100+ feet underground to an abandoned well on the property.

If this pipe is used for the grounding electrode for the service, does it need to be supplemented?

shortcircuit

 

[iwire]

Dwellings copper town water pipe has just been replaced with plastic from the street so the service needs to be regrounded.

The dwelling has an old 1.25 galvanized pipe extending 100+ feet underground to an abandoned well on the property.

If this pipe is used for the grounding electrode for the service, does it need to be supplemented?

shortcircuit

If I was the inspector how would I know that this pipe qualifies? I assume I did not see it before it was back filled.


Now if I was doing the job I would likely include that as an electrode but also drive two rods.

 

[shortcircuit2]

No, the inspector can not see the pipe in the ground...only at both ends...in the basement and at the old well.

Guess I better just drive a pair of ground rods.

I was just trying to save the 78 year old guy some money. He just had to pay $4200 to replace the copper water line that was leaking after 10-15 years in the ground. Our town is springing leaks in homeowner copper water services all over the place...and each owner is having to absorb the cost of replacement.

Thanks for the feedback...

shortcircuit

 

[tom baker]

Copper corrosion can be caused by low pH agressive water. Our water system treats the water with NaOH to raise the pH. The EPA adopted the Lead and Copper rule in the late 1990s
Ask the water company for a copy of their consumer confidence report - it will list all the EPA parameters and the tested values.
Go here for info http://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfm

Here is the link to find a contact or the CCR:
http://cfpub.epa.gov/safewater/ccr/index.cfm

Here is the link to my drinking water CCR
http://www.ci.bremerton.wa.us/display.php?id=734

 

[Dennis Alwon]

I would drive 2 rods unless you want to dig it up. I would however connect to the old pipe as well as drive the rods. The old pipe will probably be a better electrode.

 

[dana1028]

I would drive 2 rods unless you want to dig it up. I would however connect to the old pipe as well as drive the rods. The old pipe will probably be a better electrode.

Wondering if I'm reading too much into the code.

From 250.52(A)(1) - "A metal undergound water pipe..."......I was always under the impression that this 'water' pipe actually had water in it...i.e. it was being used as a water supply. With the OP's abandoned water pipe you just have a pipe in the ground that once was used as a water supply pipe but is now just a pipe in the ground.

With 'just a pipe in the ground' how would this qualify as an electrode?

[The OP indicated the well was abandoned....thus I think it fair to conclude this pipe no longer supplies water to the structure through the pipe...thus it is no longer a water pipe].

 

[david luchini]

With 'just a pipe in the ground' how would this qualify as an electrode?

250.52(A)(8) - "Other Local Metal Underground Systems or Structures"?

 

[Dennis Alwon]

250.52(A)(8) - "Other Local Metal Underground Systems or Structures"?

Thanks for answering for me :thumbsup:-- That is exactly what I was looking at earlier.

 

[jaggedben]

It kind of comes down to this... Is it possible for someone to touch the pipe and touch a metal part of the electrical system? If so, the pipe should be bonded, to provide a lower resistance path between the metal part and the pipe than someone's body might provide, in case there were an undetected fault in the electrical system.

Touching both at the same time includes if the person might be holding something long and metal in their hands. Most likely, bonding the pipe is a good idea.

 

[kwired]

If you are going to call it other rod or pipe electrode then it will need an additional augmented electrode if it does not have a resistance of 25 ohms or less. 250.56 2008 NEC. 2011 I'm sure has been reworded but basic requirements have really not changed much.

If you are going to call it a water pipe electrode then it still needs a supplemental electrode. 250.53(D)(2) 2008 NEC.

Is the cost of a ground rod really going to break the bank on this one?

 

[shortcircuit2]

IMO...the old abandoned well water pipe is now a 250.52(A) (8) electrode. I have asked the inspector for his opinion.

Wouldn't 100+ feet of 1.25 galvanized pipe 6 feet down be a better electrode than a couple of ground rods? Most homes in town are ending up with 2 ground rods for the electrode as the copper gets replaced with plastic.

I think the problem with the copper failing started when the town added something to the water for the PH level...it only seems to cause problems with the underground mains...not the piping in the homes?

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[hurk27]

IMO...the old abandoned well water pipe is now a 250.52(A) (8) electrode. I have asked the inspector for his opinion.

Wouldn't 100+ feet of 1.25 galvanized pipe 6 feet down be a better electrode than a couple of ground rods? Most homes in town are ending up with 2 ground rods for the electrode as the copper gets replaced with plastic.

I think the problem with the copper failing started when the town added something to the water for the PH level...it only seems to cause problems with the underground mains...not the piping in the homes?

shortcircuit

I would agree that this pipe will be a much better GE than any 8' rod could ever be, and just for this fact I would also bond it, then drive two rods 6' and 12' from it and just bond them to it also.

As for loosing pipes all over town, depending upon the size of this town if there is only one main set of primaries that feed the town and this is a wye system, then I would suspect that maybe there is a lost MGN somewhere between the last substation and this town??? and the MGN return current is using this water pipe system as a return back to source?

Although it is hard to belive that its not a delta system?

 

[Sierrasparky]

I would agree that this pipe will be a much better GE than any 8' rod could ever be, and just for this fact I would also bond it, then drive two rods 6' and 12' from it and just bond them to it also.

As for loosing pipes all over town, depending upon the size of this town if there is only one main set of primaries that feed the town and this is a wye system, then I would suspect that maybe there is a lost MGN somewhere between the last substation and this town??? and the MGN return current is using this water pipe system as a return back to source?

Although it is hard to belive that its not a delta system?

Why would it be more problematic with a WYE then a Delta system

 

[hurk27]

Why would it be more problematic with a WYE then a Delta system

:?

Because a WYE returns unbalanced current on the MGN back to source, a delta does not, if you loose the MGN in a WYE system since the MGN is grounded about every 4 miles and at each and every service in the system which is also bonded to all the water pipes it will return the unbalanced MGN current through all these paths instead of the intended MGN path because it was lost, the balanced delta system does not share this effect.

 

[hurk27]

We had the same thing happen at a large apartment complex, the main MGN connection about a mile down the road was lost and they started loosing water pipes, well the water company started installing plastic pies and then the voltage on all the grounding started rising very slowly, after about a year, it reached 56 volts between any grounded object and earth, and people started getting shocks in basement apartments when they standing on the tile/concrete floors and grabbed the shower water valves, we traced the problem to the MGN and the utility repaired it and it all went away, some ground rods were so badly eaten up that they looked like a tree that a beaver had been gnawing on, I had a couple of engineers tell me this was imposable but they had to agree with the results.

 

[iwire]

Wouldn't 100+ feet of 1.25 galvanized pipe 6 feet down be a better electrode than a couple of ground rods?

Sure, but if I was an inspector I should not just assume that buried pipe is metal all the way.

If I did not see it before back filling I can't count on anything.

 

[iwire]

It takes a DC source to cause electrolysis, I doubt the pipes are being damaged by the utility.

 

[shortcircuit2]

Inspector agreed that the well water pipe could be considered a 250.52 (A) (8) electrode, but felt that it should be supplemented with ground rods so if the pipe were ever dug up. I have pounded in a coulple of 8ft rods and bonded them to the #4 grounding electrode conductor in the basement of the 130 year old home. Lets hope that no one ever digs up the rods either.

 

[don_resqcapt19]

Dwellings copper town water pipe has just been replaced with plastic from the street so the service needs to be regrounded.

The dwelling has an old 1.25 galvanized pipe extending 100+ feet underground to an abandoned well on the property.

If this pipe is used for the grounding electrode for the service, does it need to be supplemented?

shortcircuit

As long as I can remember, the water pipe electrode has always been required to be supplemented for this very reason. Assuming the original installation was code compliant, there is no need to do anything.

 

[kwired]

As long as I can remember, the water pipe electrode has always been required to be supplemented for this very reason. Assuming the original installation was code compliant, there is no need to do anything.

You may want to go back and read post #1 again. He has to do something.