In a Worst Case situation where you can't haul in Rock or Such, a simple easy fix is to cut down some Scrap Trees and lay them longwise in the Ruts. I've also seen Logs used to lay Sideways to form a Bridge of Sorts to help with crossing a bog area.
Best thing to do is get a Pipe to move the water and lay it sideways, then build your other stuff on top of it. Gives the water someplace to go.
Sometimes you can get away with a simple Ditch dug out with a shovel IF you have an area for the water to go on each side to drain where the water lays on the trail.
However IF you can haul in Rock, NOTHING else beats it. You will need to Raise the area higher than you think to allow for some settling to occur.