Analysis of the hydraulic connection of the Plitvica stream and the groundwater of the Varaždin alluvia<u /><i />l aquifer

A combination of different statistical methods and flow duration curves was used to examine hydraulic connection between the Plitvica stream surrounding piezometers that capture groundwater Varaždin alluvial aquifer. Also, rainfall quantities over a wider study area were considered effect precipitation on water levels levels. The following in this paper: correlation method, auto- cross-correlation method. Correlation analysis show there is generally significant levels, with positive direction correlation. auto-correlograms for surface shows coefficient value drops below 0.2 after longer period, which indicates long-term memory system can be explained by slow thus pressure transfer. Cross-correlation analyses time series showed lag 1-2 days fairly coefficient. For relationship much weaker, 4-5 weak cross- least lag, within day, established Analyses revealed almost completely drains groundwater, except vicinity piezometer 2178 where recharges aquifer about quarter time.