Usage des ouvrages de correction torrentielle et plages de dépôt : origine, état des lieux, perspectives

Abstract

02129862 Large operations of torrent control works in the most active catchments have been launched in France by the 1882's mountain areas restoration policy, based on older pioneer works. It first implemented headwater soil and erosion control structures and plantations, although protection structures closer from assets were built on alluvial fans to trap sediment and channelize flows. Soil erosion control and the related torrential hazard mitigation continue to be financed by public grants to maintain existing systems and, if necessary, build new ones. The environmental, socio-economic and technical contexts of risk management have changed. The current use of check dams and open check dams in protection strategies may consequently need an update. This paper firstly reviews the historical emergence of check dams and open check dams. It secondly lists their function, i.e., the qualitative effect we can expect they have on hazards in the light of 150 years of tests and trials. The last section gives some perspectives on the use of these structures: why, although complicated and expensive, is it worth maintaining some headwater structures? When is it justified to abandon or even dismantled some structures? And finally what seems to be the future way of designing and planning these structures, especially the open check dams?