Groundwater quantitative status assessment for River Basin Management Plan 2022–2027 (RBMP III)

Abstract

The Groundwater quantitative status assessment is part of River Basin Management Plan 2022–2027 (RBMP III) and is used to evaluate, according to certain criteria, the 21 groundwater bodies (GWBs) in Slovenia. GWB can achieve good or poor quantitative status. The assessment is carried out with four tests, where the impact of groundwater abstraction (pumped quantities) on: groundwater quantity and water balance, the ecological status of associated surface water bodies, groundwater dependent terrestrial ecosystems and the intrusion of saline or poor water quality into the aquifer is analyzed. The final overall assessment of each groundwater body, based on the completed tests, is determined by the criterion of the worst test assessment. Based on the results of the tests, within the assessment period, 20 GWBs in Slovenia achieved good quantitative status. GWB Dravska kotlina achieved poor quantitative status, because the pumping of groundwater causes poor quality water intrusions into the deeper aquifer of that groundwater body. Within the last assessment period 1991–2020, approx. 4 billion m3 of groundwater was available annually in shallow aquifers within groundwater bodies. Groundwater abstraction (pumper quantities) in the period 2014–2019 reached an average of 135 million m3. In the area of deep geothermal aquifers of the Mura basin, abstractions were estimated to sum up to 2.5 million m3 per year. Latest numerical simulations point out induced aquifer recharge of approx. 2.3 million m3 of thermal water.