SLOPE BENCHING AND SHRUB AND TREE RESTORATION AS AN AVALANCHE COUNTERMEASURE ALONG A ROAD

The objective of this paper is to report on the results of avalanche prevention by slope benching, which is includes the restoration of on slope shrub and tree vegetation that enhances the avalanche prevention effect. The slope benching was conducted in 1993 in order to prevent snowslides on a mountain slope along a road under construction in northwestern Hokkaido Prefecture, Japan. The annual snow depth in the region reaches 3 meters and the slope is 330 meters long. The elevation difference between the roadside and the mountain ridge is about 200 meters. In order to prevent soil erosion, a water channel was dug on each bench and neither steel nor concrete was used. Before the benching, most of the slope surface was covered with chishima-zasz (a short, thin bamboo) and scattered trees. Avalanche debris including roots from uprooted trees was observed at the end of the down slope annually. The debris accumulation was caused when the smooth stems and leaves of the hardy wintering chishima-zasz fall and cause the snow accumulated on the slope to easily glide. After the benching, which is structurally mitigated snow glide, the bench surface became covered with shrubs and trees over time. Sakhalin spruce were planted on a part of the slope for growth comparison with the natural replacement vegetation. This paper presents the results of the benching work.

• Supplemental Notes:
  • Conference Proceedings available on CD-ROM.
• Corporate Authors:

  World Road Association (PIARC)

  La Grande Arche, Paroi Nord, Niveau 5
  F-92055 La Defense Cedex,   France 
• Authors:
  • Ishimoto, K
  • Matsuda, K
  • Kajiya, Y
• Conference:
  • New Challenges for Winter Road Service. XIth International Winter Road Congress
  • Location: Sapporo, Japan
  • Date: 2002-1-28 to 2002-1-31
• Publication Date: 2002

Language

• English

Media Info

• Pagination: 7p

Subject/Index Terms

• TRT Terms: Avalanches; Erosion control; Prevention; Preventive maintenance; Shrubs; Slopes; Trees; Vegetation; Winter maintenance
• Subject Areas: Highways; Maintenance and Preservation; Security and Emergencies; I62: Winter Maintenance;

Filing Info

• Accession Number: 00925123
• Record Type: Publication
• Files: TRIS
• Created Date: May 3 2002 12:00AM