Abstract Scour is one of the major causes for bridge failure. This problem represents a heavy burden for the Italian railroads in terms of operating disruption and expense for the restoration of the damaged bridges. Scour failures tend to occur suddenly and without prior warning or sign of distress to the structure. The nature of the failure is often the complete collapse of the entire part of a bridge. Furthermore the pits of erosion tend to fill as soon as the flood begins to decrease, therefore following inspections and measures, in periods of dry weather, cannot furnish indications on the maximum depth reached by erosion during the event of flood. Until recently, there has been little awareness among bridge engineers of the danger of scour, compared to the effort concentrated on structural assessment. Examination into scour on existing structures has been very limited and of doubtful effectiveness. This is reflected in the total absence or at most a passing mention of scour in most bridge inspection and assessment documents. In order to resolve these problems of scour, or to limit the effects, the Italian Railways (F.S.) has provided, up until the recent past, a series of preventive interventions consisting in the consolidation and protection of the bridge foundations. These interventions are expensive and cannot be carried out for all bridges. In recent years the consolidation works have been defined only in the cases of real necessity or where the risk of erosion is high, opting for monitoring systems in other cases. These systems, on the other hand, are able to monitor the levels of scour during a flood and therefore the danger level. Owing to the need to have systems to measure continuously the Italian Railways (F.S.) have installed two experimental monitoring systems on the River Po. The following paper intends to outline the first results of this experiment, which began in 1995: in particular, the bed movement near the pier foundation during a flood.