Why did I get an electric shock when I stuck my hand in my pool?

Question

I stuck my hand in my above-ground pool and got a mild electric shock. Other people were standing around the pool with their hands in the water, and they didn't get shocked; also, the heater and filter system was turned off.

I asked a really brainy person in my family if it was a static electric shock (like when you touch a metal doorknob), but he said that it's impossible to get a static shock from touching water; you have to get it from touching metal. I'm skeptical about that, because how else would I have gotten shocked by a swimming pool? Anybody know what happened here? I really want to know!

Answer 1

Static electric shocks are normally caused when static electricity has built up in YOUR body and the shock happens when you discharge to a ground.  We notice the shocks on pieces of metal that are grounded because metals are good conductors and they carry the electricity away quickly.  It's not normally the metal shocking us, it's us shocking the metal (unless you are talking about a large ungrounded metal object that has picked up a charge from friction--such as a car).  Any water but the purest distilled and deionized water is a good conductor of electricty and can also therefore ground a static charge.  Ever see lightning hit the ocean or a lake?  That is a static shock to a body of water, direct proof that it is possible to get a static shock by touching water.  I often get static electricity shocks at the drinking fountain at work when the water hits my lips.  People who say this is impossible don't know what they're talking about.

OK, that being said, we need to figure out what happened to you.  Do you remember if the shock you got was a quick single pinprick-like jolt, or was it a long, buzzing-like shock?  If you just got a quick zap, that would be indicative of a static shock-- it happens really fast until the charged source becomes discharged--usually on the order of milliseconds.  That would also be more likely if you were wearing shoes or something to prevent you from being grounded.  The pool should be grounded, so the charge should have gone from you to the pool.  Unlikelier is that the pool is completely ungrounded and somehow picked up a charge and discharged through you.  

A second and more dangerous scenario is that you were barefoot or standing in a wet area and the pool had an electrical short circuit that grounded through you. Other people wouldn't have felt it if they were wearing shoes or standing on dry ground.  A properly designed pool should be grounded and all appliances should have ground fault circuit interrupt (GFCI) protection.  A GFCI detects if there is any discharge to the ground (which would result in a shock when you touch the water) and cuts the circuit off.  If the pool is not properly GFCI protected, you should have an electrician inspect it as soon as possible before someone gets electrocuted.  The shock from a leaking appliance would not happen all at once, rather, it would be a long buzzing shock that would not stop until you remove your hand from the water.  Make absolute sure that this is not what happened to you, please.  

You said this is an above-ground pool.  Is it one of the install-yourself Wallmart variety?  If so, it would be easy for someone to rig up the electricity improperly and dangerously, and it may not be grounded.  A permanent pool should have been professionally installed and may have needed a permit, so it is likelier that it was wired correctly.

EDIT:  There is no pump on the pool?  No lights?  No heater?  No filter?  I'm assuming it's just a plastic kiddie pool then?  Most pools except for fill-and-drain kiddie pools have some sort of an electrical pump hooked up, even if you don't see it.  They don't have to be operating for there to be an electrical leak.  Or are there high voltage power lines running overhead or underground that could induce a voltage in the pool?  I can think of no other way you would get a lasting electric shock except through some commercial power source of some kind.  Try using a voltmeter and stick one probe in the pool water and the other probe into moist earth or a grounded wire that is not connected to the pool.  If you get any reading other than 0 volts, then there is some electrical source leaking into your pool and you should get it fixed.  If it really is an unpowered fill-and-drain pool with a consistent ground discharge voltage, then drain it and move it to another location in case there is an unknown power source charging it.

Answer 2

Jeff's answer rocks!  I just put him in my contacts, and he gets my vote for answering your question!

Answer 3

Maybe electrons travelling through the water from a loose light source in the pool caught your hand and gave you a shock. You cant get a static shock from water, static shocks are caused by frictional forces, something water definetly doesnt have!

It could also be your neurons in your brain having a quick spasm which is completely natural, or your hand for some reason was charged by electric forced before you touched the water.