User blog comment:Zhada/random water glitch/@comment-4085927-20110809103425

Random glitch, if you are mining straight down there should be no way for the water to clone its self. There are glitches that clone water but i don't see how you would have run into them making a hellevator. Check the Known Bugs and Glitches page to see if any of them apply to you. If it isn't there add it please