Swimming Pool Water Bonding

[GoldDigger]

It is bonded by the rebar in and or around the pool.

That is, by a bonding jumper connected to the rebar, just as you would use in the case of a UFER ground electrode. The concrete is already effectively grounded by its position in the earth (unless there is a non-conductive liner in the hole before the concrete gets shot). But what is still needed is the bond. That is what is made by a connection to the rebar.

 

[Little Bill]

So how did you bond the conductive gunite pool shell if there is no steel? I had the impression it was not bonded.

It is bonded by the rebar in and or around the pool.

That is, by a bonding jumper connected to the rebar, just as you would use in the case of a UFER ground electrode. The concrete is already effectively grounded by its position in the earth (unless there is a non-conductive liner in the hole before the concrete gets shot). But what is still needed is the bond. That is what is made by a connection to the rebar.

No, you don't need a jumper as the form is rebar and the gunite is shot over and around it.
A jumper would be from there to anything else that requires bonding.
You also seem to be confusing grounding and bonding when you say concrete is grounded by its postion in the earth. An eqipotential bonding grid is not dependant on its postion in the earth. True it goes under grade, but grounding is not its purpose.

 

[GoldDigger]

No, you don't need a jumper as the form is rebar and the gunite is shot over and around it.
A jumper would be from there to anything else that requires bonding.
You also seem to be confusing grounding and bonding when you say concrete is grounded by its postion in the earth. An eqipotential bonding grid is not dependant on its postion in the earth. True it goes under grade, but grounding is not its purpose.

Should have made it clearer that the bond that I was talking about was the bond from the pool shell to the rest of the equipotential grid. I interpreted the original question about how to bond the pool shell as how to bond everything else to the pool shell.

 

[Dennis Alwon]

Many gunite pools are free form where I understood that there was no reinforcing bars but just gunite formed to the earth. I can only see running the equipotential bonding in the gunite itself. That is what I was curious about

 

[kwired]

Should have made it clearer that the bond that I was talking about was the bond from the pool shell to the rest of the equipotential grid. I interpreted the original question about how to bond the pool shell as how to bond everything else to the pool shell.

The thread topic is about how to bond the pool water. If the shell is conductive and bonded then so is the pool water. To me the issue for the OP is convincing the AHJ that the shell is conductive and because of that does bond the water.

 

[Gregg Harris]

Many gunite pools are free form where I understood that there was no reinforcing bars but just gunite formed to the earth. I can only see running the equipotential bonding in the gunite itself. That is what I was curious about

From the OP
"The pool is gunite with a non-encapsulated rebar reinforced pool"

 

[Little Bill]

Many gunite pools are free form where I understood that there was no reinforcing bars but just gunite formed to the earth. I can only see running the equipotential bonding in the gunite itself. That is what I was curious about

From the OP
"The pool is gunite with a non-encapsulated rebar reinforced pool"

Here is one that I did some work in that the rebar form was put in on top of the existing pool and re-shot with gunite.











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[ggunn]

Pool water must be bonded no matter what the pool is made from. They make fittings that go in the circulation system of the pool pipes that will satisfy this requirement by bonding the fitting to the pump.

From another subforum here:

http://www.foxnews.com/us/2013/07/1...ina-girl-electrocuted-while-swimming-in-pool/

 

[ggunn]

From another subforum here:

http://www.foxnews.com/us/2013/07/1...ina-girl-electrocuted-while-swimming-in-pool/

Apparently the water was not bonded but the ladder was grounded.

 

[don_resqcapt19]

Apparently the water was not bonded but the ladder was grounded.

In that type of case the water is not any where near conductive enough for bonding the water to make any difference.

 

[ggunn]

In that type of case the water is not any where near conductive enough for bonding the water to make any difference.

If that's true, what's the point of bonding the water? It's not like it's going to catch fire.

 

[GoldDigger]

Here is one that I did some work in that the rebar form was put in on top of the existing pool and re-shot with gunite.

Since there was the existing pool shell of unknown conductivity between the rebar/gunite and the earth, the gunite shell could be bonded to via the rebar for equipotential grid and also formed a conductive shell to bond to the water to equipotential, but did not necessarily also double as an earth ground reference.
Was that an old light shell I see the green bond wire to in the pictures?

 

[GoldDigger]

If that's true, what's the point of bonding the water? It's not like it's going to catch fire.

You bond the water so that an electrode introduced into the water but not touching anything else (low current) will not create a touch potential between the water and some other metal object outside the pool.
If there is an unbonded ladder (or just steps) at one end of the pool and the hot wire is dropped into the other end, someone in the middle of the pool edge may have a touch potential of half the system voltage to a mid-point ladder that does not come all the way down into the water for example. Or the base of a diving board.
If the water bond electrode is only in one place and the conductivity of the water is low, it might not actually work as needed for that kind of case. A conductive pool shell does a much better job.

 

[ggunn]

You bond the water so that an electrode introduced into the water but not touching anything else (low current) will not create a touch potential between the water and some other metal object outside the pool.
If there is an unbonded ladder (or just steps) at one end of the pool and the hot wire is dropped into the other end, someone in the middle of the pool edge may have a touch potential of half the system voltage to a mid-point ladder that does not come all the way down into the water for example. Or the base of a diving board.
If the water bond electrode is only in one place and the conductivity of the water is low, it might not actually work as needed for that kind of case. A conductive pool shell does a much better job.

So what about the case of the electrocuted girl? Would bonding the water have prevented the accident from occurring?

 

[steve66]

So what about the case of the electrocuted girl? Would bonding the water have prevented the accident from occurring?

No, if the ladder was bonded, it bonded the water too.

The NEC prohibits electric power lines from running over the top of a swimming pool. Not having a line that can snap and fall into the pool would have prevented this.

 

[GoldDigger]

So what about the case of the electrocuted girl? Would bonding the water have prevented the accident from occurring?

Very hard to tell from a Faux News story, but possibly not.
My SWAG is that the wire hit a parking lot drain and energized the whole pool drain system (not properly bonded!) That raised the water to the level of the fault voltage. A conductive pool shell almost certainly would have helped. A water bond close to the ladder might have helped.
A proper bond between the ladder and the water supply and drain piping almost certainly would have prevented the tragedy with or without a water bond.
The water bond really only comes into play when the plumbing is all non-conductive and a single live conductor falls into the pool. It will take a low impedance ground to trigger any OCPD, and it will take good bonding to prevent the touch potential.

The lifeguard who told the swimmers to get out of the pool made the biggest error in judgement, but cannot really be blamed for that.
I strongly suspect that when all is said and done, it will be determined that the bonding (not including water bonding) at the pool was incorrect originally or had failed
All that from little or no information, of course.

 

[don_resqcapt19]

About the only thing the water bond is good for is making sure that if a two wire device that has GFCI protection falls into the pool that the GFCI will trip. I guess if there is little or no current flow it will help keep the water at the same potential as the pool deck or metal objects. If there is much current flow the water is not conductive enough to make it safe to be in the water.

 

[Little Bill]

Since there was the existing pool shell of unknown conductivity between the rebar/gunite and the earth, the gunite shell could be bonded to via the rebar for equipotential grid and also formed a conductive shell to bond to the water to equipotential, but did not necessarily also double as an earth ground reference.
Was that an old light shell I see the green bond wire to in the pictures?

The old shell also had a rebar form. They cut open the deck to redo it and I tied the new rebar to the old just as and added measure for bonding.

That is a new wet niche that you see the green wire attached to. One pic is the green #8 EGC attached to the grounding lug, and the other is the same wire after I put the potting compound on.

You have to run the insulated #8 EGC to the inside and #8 bare copper to the outside of the niche for bonding. A lot of people get confused by this. One is the EGC and the other is for the equipotential bond.

 

[mwm1752]

Curious, why all responses to Tragic Story, which by the way are what I was hoping to see, are in this thread. The point was to involve knowledgeable people to help those who may have questions (such as myself). As of yet plenty of views with no responses = knowledge lost.

 

[GoldDigger]

Curious, why all responses to Tragic Story, which by the way are what I was hoping to see, are in this thread. The point was to involve knowledgeable people to help those who may have questions (such as myself). As of yet plenty of views with no responses = knowledge lost.

Thanks for pointing that out. I did not pay close attention to the initial post and was not drawn back to it since there were no replies.
I have copied my info to that thread too. I will keep watching that thread.