I had the same results with my tent as well. Even though I was always so very worried about not having the ground tarp stick out, always water between both. Moved the tarp inside I had much better results. Don't understand the theory but wasn't going to argue with what works. If car camping I brought my plastic awning mat for my camper and put it under the tent. Water drains out of it, and kept the rocks at Bay a little. Sure don't want to haul such a big mat every tent trip, but was nice not having to crawl in mud/water to get in the tent if it rained.