Relation between temperature and intensity of groundwater circulation in Alpine massifs as a tool for predicting water inflows in underground works

The Vereina railway tunnel drilled in Austroalpine nappes encountered little water inflows. The linear discharge rates vary between 0,003 and 0,006 l/s/m (Figure 1). Two different water temperatures series have been observed in both northern and southern parts of the tunnel trace. The northern thermal gradient is equal to 0,018°C/m while the southern thermal gradient is not very different with a value equals to 0,016 °C/m. No special thermal anomaly has been observed on this site.