Bossea cave system response to an exceptional flood event

Multiparametric monitoring of dripwaters and streamwater was carried out during an exceptional flood event in November 2016 in the Bossea cave system (Southem Piedmont, Italy). Small tributaries that seep from the unsaturated zone were monitored by means of multiparametric loggers (temperature, electrical conductivity, and water level). Dripwaters were sampled immediately before and after the flood event. High frequency hydrochemical sampling, as well as continuous monitoring of the hydrodynarn­ ic parameters of the main underground river, were performed during this intense rainfall event. Major, minor, and trace elements and REE of the under­ ground river were analysed. Tue huge arnount of data shows that both the main underground river and the drips responded quickly to the strong rain­ fall event, although the monitored sites behaved in a different way; one from another. Drip sites exhib­ ited an increase of both water conductivity and temperature, while Torrente Mora showed a more complex behaviour of both T and EC during the flood. A11 the drip sites and the underground river discharges increased strongly during the exception­ al rainfall event. Dripwater hydrochemistry showed only small variations during the flood peak, while Torrente Mora displayed strong variations in all the parameters monitored.