Author(s): Ognjen Bonacci
Keywords: Karst aquifer; Diffuse flow; Conduit flow; Hydraulic conductivity; Inflow-outflow relationship
Abstract: The objective of this paper is to demonstrate the necessity of close cooperation of hydraulic, hydrologic and hydrogeologic scientific approach to karst groundwater investigations. The particularities of the karst aquifer are presented. The karst aquifer contains significant water resources, but development of these reservoirs is difficult due to the complexity of the aquifer. The key to understanding and predicting groundwater flow through them is an ability to accurately define the features and location of the heterogeneities using different scientific and engineering methods and approaches. Time and space scale issues are of a special importance for understanding and modelling of karst water circulation. Hydrogeology and geology are strong frameworks for water circulation in and over the karst. The importance of karstification index, ε, and effective porosity, n e, is explained. The main hydrologic tasks are water budget equation, definition of the catchment area and existence of strong inflow-outflow relationship. Measurement of hydrogeologic, hydrologic and hydraulic parameters in piezometer boreholes is stressed as particularly useful for the karst groundwater investigations. The hydraulic conductivity, K, is a key parameter for understanding and modelling of groundwater circulation in karst. The example of definition of hydraulic conductivity, K, for the Ombla karst spring is given.