TY - JOUR TI - Application of hydrodynamic models in reducing the indeterminacy of the input parameters for underground streams simulation AU - Đurić Duško JN - Facta universitatis - series: Architecture and Civil Engineering PY - 2007 VL - 5 IS - 2 SP - 159 EP - 175 PT- Article AB- The key issue which arises during the preparation of the input data at modeling of all the hydraulic systems is the one of the sufficient and optimal number of input data. Here, the answer to the question has been found by using the existing research in this field, with the application of GROW software package which simulates the two-dimensional streaming of ground water in the aquifer strata. Thus, the subject of this paper is: N Analysis of the required number of measuring points in order to reduce the indeterminacy down to the level where the further increase of the number of measuring points would not result in the higher quality. N Analysis of the input data indeterminacy propagation through the simulation models. The sample used for the analyses is a part of the water resource system in the aquifer of Semberija, Bosnia and Herzegovina, in the surrounding area of the town of Bijeljina. Apart from the separate analysis of aquifer as a source of groundwater, the paper specially addresses the analysis of the dominant influence of individual indeterminacies and potential for their reduction Initially, the existing data were used, and then the additional existing and input data were collected, and afterwards the results were compared. Since each new quality piece of input data contribute to the reduction of the model and system indeterminacy, for the purpose of this study, the additional observations and field research were organized. On the basis of the additional measuring and observation, groundwater flow analysis model was calibrated.