La catastrophe du Grand Bornand

This paper relates the catastrophic torrential flood which occurs on July 14th on the torrent Borne, which killed 23 persons. The storm has been very brief and strong, it caused a heavy runoff on the slopes on the half of the basin; the two torrents which joins at Grand Bornand, had two floods at the same time; therefore, the level of the water rised very quickly; the flows in the very sloping torrents were debris flow, but the solid discharge stopped at the Borne river, we compare varied estimations of the discharge and proposed finally 200 mf/s. The statistical analysis of the rain in 3 hours and of the discharge gave a value of at least, 170 years as return period. The analysis of the circulation of water and currents on the camping proved that the high slope of the camping created high velocity of the flow and this prevented people to escape

Archaeology · Flood myth · Geography · Geomorphology · Geotechnical engineering · Hydrology (agriculture) · Meteorology · Storm · Structural basin · Surface runoff · Ecology · Environmental Science · Flood Risk Assessment and Management · Geology