Impact of climate change on the stability of underground shallow cavities. The case of a tragedy in France in relation with the Seine flooding in 1910

International audienceThe present paper deals with climate change impact on stability of underground cavities due to its indirect effect on ground water levels. In France, several back-analyses have confirmed that variations of underground water tables play a key role in the genesis of surface disorders above shallow mine workings. The paper presents the forecast impacts of climate change on the behaviour of underground water tables as well as the consequences of those variations on the stability of disused underground cavities. A particular collapse that affected the Paris Basin during a major flood of the Seine River, one century ago (January 1910), with dramatic consequences, illustrates the importance of water variation impacts on the rock mass behaviour. The high sensitivity of the extracted material (very pure chalk) to water as well as the dynamics of the mine flooding process are described. The most realistic mechanisms and scenario enabling to explain massive failure of the underground workings are then discussed