How will you repair a damaged snow fence will depend upon the type of fence you install. If it is a natural or living fence, you have to trim the shrubs or remove damaged plants and replace the parts with pieces of wood. For a wooden snow fence, a bit of hammering, sawing and filling will be necessary.
You have to cut the rotten part and replace it with a new one, you can or patch the holes and cracks with wooden fillers. With the plastic or fiberglass type, damage can be repaired using epoxy resins to patch cracks and holes. However, if the damage is severe, you have to replace the entire fence with a new one.