Groundwater Vulnerability to Pollution D index map (Depth to groundwater level) in Catalonia according to DRASTIC
Depth to groundwater level distribution map expressed as an index value according to DRASTIC ranges from 1 to 10, being 10 the most shallow groundwater level (less than 1.5 m) and 1 the most deepest (more than 50 m).
The depth to groundwater level index map has been calculated from the interpolation of more than 16.000 groundwater level measurements distributed throughout all the Catalan territory, main river streams, piezometric lines and surface water masses. Depth of the groundwater table has been obtained using geospatial tools. Combining these data and the digital terrain model, it has been obtained a depth to groundwater level map and from that the “D” index map according to DRASTIC ranges.