Hydrogeological conceptual model and groundwater recharge of Avella Mts. karst aquifer (southern Italy): A literature review and update

Avella Mts., southern Italy. The paper is focused on groundwater of Avella Mts. This aquifer has been experiencing an increasing human pressure due to periods of drought and growth in groundwater extraction. A novel hydrogeological conceptual model was developed, and groundwater recharge was estimated by two approaches. The study was carried out by an in-depth literature review and a GIS-based analysis of geological and piezometric data, ground-based meteorological and remotely sensed data. The new hydrogeological conceptual model allowed to reconstruct the aquifer lithology, its deep geometry, and, for the first time, groundwater flow scheme. Five groundwater basins were recognized with distinct outlets and subsurface outflows, suggesting a new aquifer compartmentalization in-series groundwater basins. Some basal springs are fed by autonomous basins with smaller extension, while other springs have dried up completely. The groundwater recharge varies from 7.30 to 6.90 m3/s as estimated by Turc formula and MODIS data, respectively; the values are comparable among them, confirming mutually the validity of approaches used. The comparison with previous studies highlights variations and changes for both the hydrogeological conceptual model and water balance, linked to natural and anthropogenic factors. The results obtained represent a way for supporting sustainable management of groundwater, waterwork systems security and groundwater-dependent ecosystems protection of a large sector of Campania region. [Display omitted] •An in-depth literature review of Avella Mts. karst aquifer was performed.•A novel GIS-based hydrogeological conceptual model and a multi-approach groundwater recharge estimation were developed.•Reconstructing the aquifer structure and groundwater flow allowed to define new groundwater basins.•The approach and results can support decisions for sustainable groundwater management.