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Electric lake? 1

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Skogsgurra

Skogsgurra

Electrical
Mar 31, 2003
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This time of the year (when calves are born with double heads and nature in general behaves in an unpredictable manner - we call it "rotmonth" because food can't take the heat and humidity very well). This time of the year, as said, we also hear new and old urban myths. One of them is the electric lake.

This happened: One guy was swimming across a little lake when he felt a tickling in his fingers. It was in a confined area and he could swim out of and into that area. He told other people about it and now it seems that most everyone can feel it - no matter where in the lake they happen to wet their feet. So, I think that most of this is due to a "me too" effect. But the first guy seems to be sure about what he felt.

There are three major pipes terminating in the lake. Two are for snow guns (not in operation during summer) and one is the outlet from a sewer station (yes, very clean). The pipes are said to be stainless steel in the ground and some plastic material in the water.

Questions:

A Anyone had this before?

B What standard measurement techniques are there?

I plan to do a "potential map" using a DMM and a surface electrode shaped as a with cylinder about 1/4 sqm external surface (an ordinary bucket - that is). I will use an iron bar that I just let drop down to the bottom and sink into the mud as a counter-electrode. I will take readings with a high-impedance DMM (it has Gohms on one range) to see if there is anything at all. After checking that, I will switch to a relevant range (all other ranges have 10 Mohms) and then take down the readings across the "offending" part of the lake. I will use a GPS to get my coordinates.

I may also bring some fishing gear.

Comments invited. Especially if you have done anything like this before.

Read all about it on Sorry only in Swedish. But there is a picture showing a couple of guys trying to "ground" the lake. ;-)

Gunnar Englund
 
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Great shot Gunnar!
That guy in the water there said it was tingling?

jraef; Yeah me too!

BJC; Yeah great idea. The powered rubber ducky could tow an electrode two meters behind for the gradient. It's eyes could flash (red) with rate depicting voltage.

Keith Cress
Flamin Systems, Inc.-
 
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This is seriuos matter, boys! Leave the rubber ducks out for a while, willya?

The guy in the lake is a lawyer. We talked about witness psychology. And he still says he feels the tingling. But he doesn't say it is due to electricity. He never did. Others did.

I find this very interesting. Actually, I think it is a parallel to magnetic field sensitivity (which I deny the existence of). This is a very small lake and people talk a lot to each other on the beach. Someone has felt something that he/she cannot explain. Someone has probably put forward that it must be the new pump station (it was installed last year) and that it must be "something electric". Theories like that catch on like praire fires if allowed to develop. I think/hope that my measurements and the full page article about it will put an end to that part of the speculations. But you never know - people love catastrophe theories.

Gunnar Englund
 
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Skogsgurra,

I noticed you were pretty thorough measuring different depths, places, orientations, etc. But what about the time factor? I'm guessing the pumps don't all run continously.

I agree with Waross, too. Ditch the capacitor and look at the DC coming from the pipe's cathodic protection as well as AC.
 
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My guess,
the water is sooooo coooold, its the onset of hypothermia!
BTW, how is the fishing?

Scott

In a hundred years, it isn't going to matter anyway.
 
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stevenal,

We made sure that the phenomenon was present when we measured by having our "human indicator" swimming in the lake. He said that the tingling was there all the time. The pipes are for two snow canons and they are never run during summer when people swim in the lake.

Re capacitor and DC/AC. I measured with and without capacitor. I also used the different modes (AC, AC/DC, DC) of the instrument. Zero in all cases.

Before the measurements, I had calibrated the measuring system in a plastic pool using the secondary voltage of a small transformer (yes, RCD used) ans two metal cylinders. I got the expected readings and the fact that we could see a small voltage gradient (9 mV/m) close to the pipe serves as an extra confirmation.

An experiment that we didn't do was to use our "human indicator" in other lakes and see if he feels the same thing there. That ought to be done.

Gunnar Englund
 
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Just a far fetched thought, although I have no idea why it would result in a "tingling".

Many snow making systems are large motors and use solid state soft starters. Assuming they are left energized when not in use (not a good idea, but let's run with it), SCRs and their snubber circuits have leakage current. If the motor winding insulation was damp and leaking to the frame a little as well, it could be getting to the pump somehow (solid coupling, shaft grounding bushings etc.) and would eventually make it out to the pipes (assuming they are metal). A simple test would be to ask the snow equipment owner to open the circuit breakers (if they aren't already) and see if it goes away.

Why that would be picked up by a swimmer I have no idea, they would be at the same potential as the water, no?

http:/Eng-Tips: Help for your job, not for your homework Read faq731-376 [pirate]
 
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Well the next step is obvious.
We need to capitolize and form a bottling company. We need a catchy name and a bottle that looks like a battery. Go back to the lake and do some more research, this time take some of the Sweedish bikini team we'll need the pictures for the bottle label.
I am sure this stuff will also cure everything from toe nail fungus to dandruff.
Where do I send my money?
 
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If the tingling is not electrical in nature, could it be a chemical irritant ?

Any factories or manufacturing going on around that lake ?

How about mild stings from Jellyfish or something similar ?
 
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BJC,
I am glad that you abandoned the rubber duck theme and turned to something more lucrative. Yes, it cures toe nail fungus and dandruff, and also incapacities in-between - if you see what I mean. You can send the money to me.

Warpspeed,
No factories. Just a conference hotel. I have tasted the water. No problems. I think that we can bottle it without any further processing. No need to filter out yellyfish, they do not live in fresh water. You can send the money to me.

Smoked,
I wouldn't know about them li'l fish nibbling my hair. And, yes. I took a dip. Don't feel an eel and nothing else. You can send the money to me.

Jeff,
How, when, where, of whom, why did you take that photograph? I know it isn't you. And that grin indicates the bucketeer is fully aware of the purpose of the photographing. There is some residual voltage between pump/motor housing and ground. It is because there is a voltage drop in the PEN between transformer and the PCC where the pump is connected. But it results in no more than the now infamous 9 mV/m close to the pipe. Nothing in the lake. You can send the money to me.

I2R,
That's a very probable reason. But the water is quite warm by our standards - about 22 celsius. The fishing was lousy. Probably because of the electric environment. You can send the money to me.

To all, and Jeff in particular. I think that we have lots and lots of abalone eggs floating around in the lake. That's probably what the customers feel.

I think it is time to close this thread. I thank you all for invaluable help in establishing a workable theory, designing measurement equipment, evaluating results and being helpful in general. And, by now, you know where to send the money.



Gunnar Englund
 
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Don't know from where those hypothetical abalone eggs come. Maybe dropped from an airplane? Do abalones get eggs at all? Or do they bear little abalones? I have no idea any more, wish I hadn't tried to measure that lake at all.

Gunnar Englund
 
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i I recently had a conversation wiht a person who claimed to get headaches from cell phones ( wheather transmitting or not) and WiFi transmitters. I googled up all the info I could for him. As with the radiation from monitors Sweden has some research on the subject. As it wasn't my field I gave him the references and told him to hire an engineer that was up on the area. He had already hired one to survey his house.
I came to think his problem could have been solved with a tin foil hat. Maby your swimmer could have used a similar cure.
 
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Maybe a concrete flotation aid...?


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image.php
I don't suffer from insanity. I enjoy it...
 
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Buy more land around the lake. Spread more rumors. Get more technical. Expound on the curative nature of the tingling. Open a Spa on the lake. Make lots of money. Donate it to charity and cancer research. Then, the tingling lake will really be acure for cancer!

jsolar
 
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Interesting. Maybe when the swimmer moved into a slightly warmer section of the lake, the numbness started wearing off and he started feeling the tingling? Makes sense.
 
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