Sorry if this has already been covered before but I couldn't find anything when searching. I want to sink a few posts near our fire pit so I can set my hammock up. Only problem is after you do down about a foot and a half the holes start to fill up with water. I just removed a bunch of old railroad ties and a few newer treated fence posts the other day all of which were severely rotten. What's the best way to prevent this from happening? Would some sort of metal piping be a better option?