Agree you have some kind of serious problem, within either the house wiring or something plugged into your load. Water pipes are a dangerous place from which to take a safety ground, although many older homes were done this way. Telco used to do that too but they know better now. A local lightning strike could light up someone washing their hands, in the shower, or doing dishes!
Sparking Ground Wire
"My electrical panel in my house is grounded to my cold water inlet. I replaced the worn clamp to the pipe and noticed a small spark when I touch the ground wire to the pipe. What could be causing this. My understanding is that the ground should be dead and should have no current. Any suggestions?"