Mild electric shocks in pool
I have been living in my house with a 25,000 gallon inground vinyl pool for nearly six years. The pool also has an attached spa.
Yesterday, we noticed that when in the water at the steps in the shallow end and touching the concrete pavers right in front of the steps, we get a buzzing shock where we touch the concrete. Also, a "stinging" or "biting" sensation is felt on the body part where it meets the water surface (e.g. ankles). Also, if someone is sitting on the concrete, completely out of the pool, and someone in the pool touches that person, both people feel the buzz. Interestingly, no shock is felt when we touch the metal handrails on either side of the steps. The shocking by the steps is mild enough that quickly walking in and out of the pool does not cause you to feel it, but if standing stationary on the concrete and dipping your hand into the water and holding that position, it is enough to make you yelp. It's possible my husband noticed a very slight sting when in the pool and dipping his finger into the spa, which disappeared once he grasped the side of the spa with his other hand. He only felt the sting where he had a cut on his finger. This was a couple of months ago. No one else noticed anything significant until yesterday, and we even had a big pool party three days ago.
Today, I turned off the main breaker of the house and went out and tested it, and the shock still happens when I stand on the steps in the water and touch the concrete pavers. The intensity of the shock is rather localized to about a two- to threee-foot area in front of the steps. The farther you place your hands from this epicenter the weaker the buzzing gets. I tested this by the ladder at the deep end and various other random spots, and this is the only place I feel it. I also could not duplicate what my husband was talking about with the spa.
Some more info that might be relevant -- we live across the street from a high-tension-wire tower. Our soil is sandy/pebbly. Last summer, a transformer (I think) across the street exploded out of the blue, on a beautiful sunny day, and caused our power to flicker for a second and our next-door-neighbor's power to go out completely until LIPA (Long Island Power Authority) came to fix it. This explosion was in the front yard on the opposite side of the house from where I feel the shocks. The tower is on the same side of the house, however.
What puzzles me most is that no one seemed to notice this before this year, and I know people have sat on the concrete with their feet in the water many times. What could have changed?
Until this is corrected or diagnosed, is it safe to swim?
Thanks --
Jody