Dock on the lake with ground current

In meantime I'd either disconnect power including the grounding conductor to the dock or not let anyone swim near the dock.
 
Regarding the "NO SWIMMING" recommendation, a very common cause of death is drowning. The current causes a person's muscles to contract, making them lose the ability to use their arms and legs to propell themselves towards the ladder (or towards the shore). I imagine it to be a truly terrifying way to die, given that your mind is screaming at your arm and leg muscles, commanding them to push you to safety, and you realize that they cannot obey that command (the current flowing through their body overrides the command).

Take this warning seriously! Post a sign that says more than, "NO SWIMMING." Add to that sign something along the lines of, "If you swim here, you will die"!
 
I understand and have read several tragic instances of shock induced drowning.

I don’t want to seem flippant but completely disconnecting electrical from the dock (twist lock cable) renders the dock about the same as swimming on a floating log in the lake. It seems like it would be silly to not use the dock (while disconnected) while watching boats go by all day with people in the water in the vicinity of the dock and all the neighbors on our point using theirs?
 
gaspower said:
I understand and have read several tragic instances of shock induced drowning.

I don’t want to seem flippant but completely disconnecting electrical from the dock (twist lock cable) renders the dock about the same as swimming on a floating log in the lake. It seems like it would be silly to not use the dock (while disconnected) while watching boats go by all day with people in the water in the vicinity of the dock and all the neighbors on our point using theirs?
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The tricky part is making sure it stays disconnected while the No Swimming signs are down.
 
gaspower said:
That’s fair, it’s a dock for our house, no one uses it but our family. No one else but me is empowered or physically capable of plugging it in (kids can’t reach)
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That's all well and good. But the current in the water near your dock could originate from a power connection at some other nearby (or even not so nearby) dock. Get the neighbors involved, hire an expert, and make this go away permanently.
 
charlie b said:
That's all well and good. But the current in the water near your dock could originate from a power connection at some other nearby (or even not so nearby) dock. Get the neighbors involved, hire an expert, and make this go away permanently.
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Heard Charlie!
Making calls today. Thank you and everyone else for the help here! I'll be sure to report back once this is concluded.
 
I spoke with @LarryFine ’s friend (big help!) turns out we went to the same engineering school (Georgia Tech). He suspects based on what I measured that it is most likely elevated neutral voltage perhaps related to the fact our community is 20+ miles from the substation.
Plot thickens further-
Found out that a neighbor was recently shocked while cleaning out their hot tub, standing in water on concrete pad and touched the (grounded) frame of the hot tub. the POCO came out and ”checked things” and found 2V hot tub frame to water on ground. POCO didn’t really have a solution other than mentioning the Ronk Blocker (that someone else mentioned earlier in this thread.

I spoke with the POCO who confirmed he has personally checked all the wires from our point (end of the line) back to the substation. He confirmed this issue tends to be worse when it’s dry (lower earth conductivity, already poor due to rocky soil) and we’ve been in a 2-3 week hot and dry spell. It doesn’t help that in the 3 communities served by this long single line homes are continually being expanded or rebuilt so electrical load is going up.
POCO rep mentioned they are investigating the Ronk Blocker but are concerned it’s just a bandaid. They also aren’t sure if they would provide it or charge us (I would seriously push back on this as it is installed on utility side of meter and solving their issues). I think the guy is being earnest there just isn’t an “easy” or inexpensive solution so they are kind of stuck and like 2 years ago hoping people stop complaining or it goes away. I asked about consulting others and apparently they have reached out to their normal consulting engineers and TVA and no one seems to have a great solution.

My next step is to speak with the executive director of the POCO and if they don’t start moving, file a complaint with TVA. This issue has been present for years and they just keep ignoring it and hoping it goes away.

Appreciate any guidance! In the meantime we’ll continue to disconnect the dock when swimming.
 
My experience has been getting TVA involved is a positive step. They have more expertise, more engineers and a lot bigger budget than your POCO. Over the years they have been instrumental in solving some POCO related issues locally.,
 
augie47 said:
My experience has been getting TVA involved is a positive step. They have more expertise, more engineers and a lot bigger budget than your POCO. Over the years they have been instrumental in solving some POCO related issues locally.,
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@augie47 Would you even bother trying to give the executive director a chance or just go straight to TVA?
 
gaspower said:
I spoke with @LarryFine ’s friend (big help!) turns out we went to the same engineering school (Georgia Tech). He suspects based on what I measured that it is most likely elevated neutral voltage perhaps related to the fact our community is 20+ miles from the substation.
Plot thickens further-
Found out that a neighbor was recently shocked while cleaning out their hot tub, standing in water on concrete pad and touched the (grounded) frame of the hot tub. the POCO came out and ”checked things” and found 2V hot tub frame to water on ground. POCO didn’t really have a solution other than mentioning the Ronk Blocker (that someone else mentioned earlier in this thread.

I spoke with the POCO who confirmed he has personally checked all the wires from our point (end of the line) back to the substation. He confirmed this issue tends to be worse when it’s dry (lower earth conductivity, already poor due to rocky soil) and we’ve been in a 2-3 week hot and dry spell. It doesn’t help that in the 3 communities served by this long single line homes are continually being expanded or rebuilt so electrical load is going up.
POCO rep mentioned they are investigating the Ronk Blocker but are concerned it’s just a bandaid. They also aren’t sure if they would provide it or charge us (I would seriously push back on this as it is installed on utility side of meter and solving their issues). I think the guy is being earnest there just isn’t an “easy” or inexpensive solution so they are kind of stuck and like 2 years ago hoping people stop complaining or it goes away. I asked about consulting others and apparently they have reached out to their normal consulting engineers and TVA and no one seems to have a great solution.

My next step is to speak with the executive director of the POCO and if they don’t start moving, file a complaint with TVA. This issue has been present for years and they just keep ignoring it and hoping it goes away.

Appreciate any guidance! In the meantime we’ll continue to disconnect the dock when swimming.
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Is there any transmission lines running parallel to local distribution lines? Particularly ones over 100kV. Capacitively coupled voltage can develop on the local distribution in those situations. You see under 100 kV ran on same poles as lower voltage lines often but pretty much never see over 100kV ran that way. I still seen capacitive effects when a 230kV line was on one side of a roadway and a 12.47 distribution line was on other side of road and still had a couple volts of NEV on a 480/277 service supplied from that and in no load condition on the service. POCO acted like there was nothing that can be done. I've wanted to come back and see what kind of current this may be able to produce, so far haven't been back. Was on irrigation service I installed about a year ago. Is a client I do a lot of work for so eventually will probably get an opportunity. Wasn't shocking anyone when touching equipment but what got my attention was I was all done out in the field and was hooking up conductors at utility disconnect on pole out at the road and I got a spark when I was landing the neutral conductor and that got me investigating why that was happening.

My concern is if something breaks down, and of course everything will be wet since it was running right before it broke down, if increased conductivity because of wetness could raise the shock potential. It was in pre season and things were dry when I discovered this issue. I don't know if things may get better or worse if everything is wet around this could see scenarios where it could go either way.
 
gaspower said:
@augie47 Would you even bother trying to give the executive director a chance or just go straight to TVA?
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Everytime we have had TVA assistance it has been through the local POCO.
I would think first I would ask POCO to get them involved
 
The two obvious, but not easy or inexpensive solutions on the POCO side are:
1. Increase the conductivity of the primary return path, by increasing the conductivity of the metallic neutral and/or greatly increasing the number and quality of POCO ground electrodes along the entire long path. If they currently only have ground electrodes at poles with transformers, it may be possible to increase the number of grounds inexpensively. A more directed solution than effectively relying on customer GES, but it might still be considered a band aid.
2. Decrease the amount of primary neutral current. Either go from a single phase with earth return to a two phase feed to the transformer primary, or go to a full balanced three phase. If the load in the entire area is increasing, then going to two phase conductors may end up being the cheapest way to increase the line capacity and would eliminate neutral current completely.
If enough customers installed a neutral isolator, it could make the original POCO neutral voltage offset worse by taking those customer ground electrodes out of the picture as a POCO neutral current path.
 
mtnelect said:
How many wells are pumping water out of the lake ?
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Our point has a single community well and water system serving 23 homes. The next point has something like 8 wells serving 1-3 homes each. The third point has individual wells.

All of these wells are deep drilled into granite, not in the lake.

I am not aware of any pumps directly in the lake and I notice that kind of thing.

Why do you ask?
 
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