New results from sediment transport measurements in two Alpine torrents

In the Erlenbach Torrent (Swiss Alps, 0.70 km 2 ), the intensity of bed-load transport is recorded indirectly and continuously by special sensors installed in the bottom of the channel. At the observation station in the Rio Cordon Torrent (eastern Italian Alps, 5 km 2 ) coarse bed load is separated from water and fine sediment, and the volume of both deposits is recorded. The Erlenbach shows a much more pronounced response to similar rainfall conditions. The geological conditions lead to a lower slope and channel stability in the Erlenbach than in the Rio Cordon. In both streams a relationship exists between the sediment load of a flood event and the corresponding runoff volume. A trend towards equal mobility is observed for higher discharges. Peak bed-load transport may occur before or after the flood peak.