Portable crossings for weak soil areas and streams

To access forest products, streams typically need to be crossed by heavy equipment. In many cases, the access is only needed for a short time. The cost and time involved to construct a permanent crossing exceeds the need. Also, permanent access into the area is unwanted, making it necessary to remove the crossing that closes the road. Removal may cause pollution to the stream and continuous erosion problems, especially when culverts are used. A possible solution would be portable, temporary, reusable crossings made of readily available, inexpensive materials. The U.S. Department of Agriculture Forest Service has investigated this type of crossing option. Several products were considered as potential crossings. Five crossings were chosen for field trials: pipe mats, gratings, Terra Mats, wood pallets, and wood mats. All five crossings work well, although each has different strong and weak points. Most of the work has been performed in Florida. Conditions in other states will require different design modifications and improvements. Although quantitative information is still being analyzed, qualitatively, the crossings greatly reduce impact to weak soils of stream beds. This impact was observed to be lower particularly when compared with using no crossing or removing a permanent crossing.