ESA-IAP - Monitoring Alpine Transportation Infrastructure using Space Techniques

Rockfalls and landslides are natural hazards of special relevance to mountainous areas with severe human and economic consequences. The densely inhabited Alps, with its large network of transport infrastructures, are particularly sensitive to these types of hazards. An efficient survey of the movement of unstable slopes above infrastructures and of the stability of the infrastructures themselves is of high importance. Hence, the scope of our feasibility study is to provide services to the Alpine Transportation Infrastructure which are based on the integration of the space techniques SAR Interferometry and GPS/GNSS. The main information to be provided is ground motion, which can include motion of the transportation infrastructure (railway, roads, ...), motion of rocks or terrain slopes above transportation infrastructure, and motion caused by tunneling. The users proposed for this feasibility study are considered key users among the railway and road infrastructure operators, including the main national railway operators for Switzerland (Swiss Federal Railways, SBB), and Austria (Austrian Federal Railways, OBB), the Swiss Federal Roads Office (ASTRA), and the Swiss Federal Office for the Environment (FOEN). Ground motion monitoring needs to be done at different spatial and temporal scales using a variety of techniques, in order to evaluate mass movements. Our proposed service will provide ground motion information and slope stability information including the following four elements: 1. analysis of historic satellite SAR data time series to get an inventory of instable slopes (GAMMA) 2. use of new satellite SAR data to do a monitoring of slope stability (GAMMA) 3. terrestrial radar interferometric measurements to provide locally much higher flexibility to the area measured and the time intervals considered in near real time (GAMMA) 4. GPS/GNSS data with advanced processing and communication techniques to complement locally the above radar methods (INAS) All four service elements have some space assets. The implementation and the processing of cost effective single-frequency GPS data observations is done by INAS using a Wireless Sensor Network (WSN). With the proposed integrated system many of the present limitations of currently used methods can be overcome to obtain a cost benefit (economic and non-economic) with the new service. Consequently the key users among the railway and road infrastructure operators confirm their interest and a high potential relevance of the proposed service.