Long-term groundwater database and assessment for the Mediterranean region

The Mediterranean region faces water security challenges with increasing water demand and climate change effects. Groundwater has become a key resource for water supply and economic development in the last decades, however, its budget remains poorly understood. The distribution of piezometric data in the Mediterranean has a very contrasting distribution. A large portion of them is not centralized and openly accessible, resulting in lack of detailed assessment of groundwater trends and their controlling factors at the regional Mediterranean scale. The objectives of this work are: i) the creation of a long-term and, possibly, the most comprehensive database for groundwater dynamics in the Mediterranean region, ii) the identification of trends and clusters on groundwater levels, and iii) the identification of the relationship between trends and climatic and hydrogeological drivers.

Over 10,000 time series of groundwater level have been collected from national and regional authorities and the literature. The data come from eight countries in the Mediterranean region and have been post-processed into a common format. A search for seasonal patterns and long-term trends is performed then clustered accordingly. Furthermore, the influence of controlling factors such as precipitation and hydrogeology on the groundwater dynamics and trends are assessed. Significant groundwater level changes have been identified at a regional scale and used to provide insight into groundwater level change drivers’ in the Mediterranean region. The database is the result of a unique joint effort between regional groundwater experts to collect groundwater status information in the Mediterranean region and will serve as the foundation for future research on the influence of anthropogenic drivers and the prediction of groundwater depletion hotspots.

This work was developed under the scope of the InTheMED project. InTheMED is part of the PRIMA programme supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 1923.