The black plastic(?)pipe from my fresh-water cistern is frozen and its 5 feet underground. The pump is in the basement and seems to be primed but I assume its trying to pull a 20 foot ice cube thru the line. I have a 100 watt lightbulb hanging inside the cistern and it seems toasty warm in there. The run of pipe is about 20 feet in length.Can anyone help? I’m getting tired of toasting snowballs for water.