Groundwater Protection and Climate Change Predictions of a Complex Dinaric Karst Catchment. A Case Study of the Bokanjac-Poličnik Area, Croatia

Abstract

The paper deals with two main issues: climate change impact on water supply and sanitary protection zones of a very sensitive Dinaric karst catchment “Bokanjac-Poličnik” in Zadar area, northern Dalmatia, Croatia. Within this complex hydrogeological system there are five public extraction sites (Bokanjac wells, Jezerce estavelle, Oko well, Golubinka spring, and Boljkovac well). Their catchments (subcatchments of the Bokanjac-Poličnik system) are interwoven and share common areas—at this moment there is no possibility of their delineation and they should be treated as one hydrogeological karst system. Since this area is close to the Adriatic Sea coast, some of these water supply sites are subjected to the underground seawater influence. In the paper it is discussed how changes (decreases of recharge) of water balance will cause decrease of extracted quantities and possible deterioration of water quality (increase of salinity). Therefore, sanitary protection zones should be established and further research of this karst system corroborated by the continuous water quality monitoring is needed, with the special regard to climate changes.