Assessment of the groundwater quantitative status in the Aosta Plain (North-West Italy): applicability of the national guidelines defined by ISPRA

The EU Water Framework Directive requires Member States to assess the quantitative and qualitative status of groundwater bodies and to achieve a good status by 2027. The present study was developed in order to assess the groundwater quantitative status in the Aosta Plain (NW Italy), following the methodology proposed through a guideline defined by the Italian Institute for Environmental Protection and Research (ISPRA), with the aim of supporting local authorities in their periodic assessment of water bodies status. In the study area, during the period 2000-2017, groundwater levels were measured in 213 wells and piezometers. Performing the four tests required by the abovementioned guideline, the quantitative status was assessed on the basis of multi-year groundwater level variations, water balance and the interconnections of groundwater with surface water bodies and groundwaterdependent ecosystems. A good status was assessed for the study area, although some critical aspects emerged from the application of the guideline methodology: the data collected by the monitoring network are not sufficiently robust in terms of sample size, spatial distribution, temporal interval and frequency to fulfill the requirements of the guideline methodology. Therefore, some recommendations to improve the data quality and better address the future assessment of groundwater quantitative status were given.