hello Harv, I dont claim to know about road building. I built my road about 2 yrs ago, I just raised the road with the rock ,that way you wont have to worry about flooding. I didnt bother scraping the top off because it was about 5 feet thick of soft topsoil, I just laid down a 6 in. layer of pit run (4-5 in. rock),drove on it, than a foot thick of what we call 3/4 crush to lock it together. I figured I would have to add more rock after a while but it has not even shown any signs of deteriorating . I guess it depends on your money/time situation , I think puting fabric down if your not going to pave is overkill. (that stuff is spendy!)