Kovač, Zoran; Parlov, Jelena; Barešić, Jadranka
(2018)
Environmental isotope research for a more efficient protection of the future Kosnica well field (Zagreb, Croatia).
In: Ristić, Goran, (ed.) Sixth International Conference on Radiation and Applications in Various Fields of Research, RAD 2018, Ohrid. Niš, Srbija, RAD Association, p. 353
.
Abstract
The Zagreb aquifer presents the main source of potable water for the City of Zagreb and part of Zagreb County, and is protected by Croatian state government. In the last decades issues regarding groundwater quantity and quality have been observed. Groundwater levels are declining in average 1-2 m per decade, generally due to lowering of the Sava River bed and excessive pumping. Currently, groundwater for water supply is pumped from six different well fields. There is new regional well field Kosnica on-going project, with aim to avoid groundwater quantity issues in future, especially in dry
periods. Isotopic research at Kosnica site has been performed in 2016. Samples from the Sava River, Zagreb precipitation and groundwater from 10 observation wells were taken on monthly basis. The Sava River has been identified as a main boundary condition of the Zagreb aquifer. The influence of this boundary, on groundwater levels in the Kosnica area, has been investigated. Kosnica well field is located approximately 800 m from the Sava River what suggested, as well as all the results of previous
research, that the Sava River will be the main source of recharge for the new well field. Previous researches recognised three main zones of identical groundwater table changes in time. Recession
curve models also revealed areas near the river with higher impact of the Sava River on groundwater levels. Water stable isotopes (2H and 18O) were determined by liquid water isotope analyser, Los Gatos Research. Data was prepared, processed and interpreted in LIMS (laboratory information
management system). 3H activity was measured by liquid scintillation counter (Quantulus 1220) and samples were electrolytically enriched before measurement. The results of environmental isotopes measurements in groundwater near Kosnica well field in the Zagreb area indicate strong connection between the Sava River and nearby observation wells. Accordingly, mixing of water from the Sava River and groundwater is occurring in the near vicinity of the Sava River and it weakens further away. Furthermore, local precipitation has a small contribution to groundwater recharge and attention needs to be directed to the Sava River. Determined groundwater velocity in combination with existing Croatian legislation point to the distinction of two different protection zones between the Sava River and the Kosnica well field. The results of this study allow better understanding of the relationship
between surface water and groundwater and consequently more precise definition of the sanitary protection zones of the Kosnica well field.
Actions (login required)
 |
View Item |
4176
UNSPECIFIED
Download Statistics
Download Statistics
