A sand fence or sandbreak, similar to a snow fence, is a barrier used to force windblown, drifting sand to accumulate in a desired place. Sand fences are employed to control erosion, help sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas. Sand fences are also commonly employed following storm events in order to aid in the dune recovery process,[1] particularly in developed areas where dunes are critical for protection of property. [2]
A typical construction is to attach a perforated plastic sheet to stakes at regular intervals, similar to construction site fencing or temporary sports field fencing. Another is a cedar or other lightweight wood strip and wire fence, also attached to metal stakes. A permanent sand fence is generally of larger wooden poles set deeply into the ground with large wooden planks running horizontally across them.
The drifting and settling of sand behind and in front of such a fence occurs because the wind speed on both the downwind and windward sides is less than that on the far windward side, allowing light materials such as sand to settle.[3] This creates a pile both in front of and behind the sand fence causing more sand to drop out. Conveniently the sand does not drop on the barrier itself, otherwise it would soon be buried and rendered useless.[4]
See also
editReferences
edit- ^ Miller, Deborah L.; Thetford, Mack; Yager, Lisa (2001-01-01). "Evaluation of Sand Fence and Vegetation for Dune Building following Overwash by Hurricane Opal on Santa Rosa Island, Florida". Journal of Coastal Research. 17 (4): 936–948. JSTOR 4300253.
- ^ Nordstrom, Karl F.; Lampe, Reinhard; Vandemark, Lisa M. (2000-01-01). "Reestablishing Naturally Functioning Dunes on Developed Coasts". Environmental Management. 25 (1): 37–51. doi:10.1007/s002679910004. ISSN 0364-152X. PMID 10552101. S2CID 24849753.
- ^ Campbell, E. (March 1975). Snowdrift Structures. Avalanche Protection in Switzerland (pp. 103-116). Fort Collins CO: General Technical Report RM-9, USDA-Forest Service.
- ^ How To Install Snow Sand Fence-Guidelines