So, I think I screwed this up... I have a depression that runs through my pasture that stays wet pretty much all of the time. I need to be able to cross over to bush hog, mow around my pond, etc. I placed 2 12" drainage pipes (corrugated HDPE) and backfilled with gravel. Problem is the gravel ended up being much thicker than I anticipated on the approach to the pipes. My tractor gets almost to the pipes then just starts spinning the tires and digging into the gravel. I need suggestions on how to fix this? Do I need to remove the gravel and build up with dirt first? Can I pour bagged concrete on top of it and wet it down to try and keep the gravel from spreading under the weight of the tractor? Any help if greatly appreciated.