Integrated hydrologic and hydrogeologic modelling for basin scale subsidence analysis [thesis]

Mattia Ceccatelli, Universitätsbibliothek Braunschweig, Matthias Schöniger, Fabio Castelli
2021
Land subsidence, together with landslides and floods, represents one of the main natural hazards that affect several countries all over the world, potentially causing significant damages to buildings and infrastructures. In particular, Firenze-Prato-Pistoia basin has a long experience of ground deformation related to groundwater withdrawal. InSAR satellite data collected since 1992 have revealed the presence of several subsiding areas in the basin, such as the south-eastern portion of Pistoia
more » ... ty. Sentinel-1 persistent scatterer interferometry measurements for 2015–2018 confirmed the long-term subsidence of this area, associated with intense horticulture (plant nurseries). At the same time, Sentinel-1 data revealed the unexpected movement of Pistoia historic center, which has always been considered stable in the past. To identify the complex relationship between aquifer conditions and ground displacement, a hydrogeologic model of the Pistoia aquifers was developed, applying an integrated modelling procedure. This approach was firstly tested in a small pilot basin, to confirm the reliability of the numerical procedure, obtaining promising results. Hydrodynamic-parameter distributions, calibrated and validated by means of Sentinel-1 PSI measurements, suggest that subsidence in Pistoia area is probably related with the combined impacts of groundwater extraction and highly compressible aquitards. To evaluate the potential evolution of ground displacement, numerical simulations were extended until 2050, using regional and global climate model data, analyzing three different pumping-rate scenarios. This, together with damage information of buildings collected on the field, led to the development of several subsidence hazard maps of Pistoia city that display the influence of groundwater extraction in controlling land subsidence in the area. The present study enhances the importance of developing proper groundwater management policies, especially in alluvial aquifers made of fine compressible sediments, in order to sust [...]
doi:10.24355/dbbs.084-202112021339-0 fatcat:chlvn3axszcgjpgwbieecg2wfm