IMPACTS OF THE RESERVOIRS ON THE RIVER LOW FLOW AND MEASURES TO MITIGATE THE NEGATIVE EFFECTS

This paper aims to highlight the impacts of the reservoirs on the low flow downstream of dams. It is based on the analysis of the flow data sets (mean daily and monthly discharges, minimum monthly discharges) provided by gauging stations located downstream four reservoirs in Romania: Gilău, Siriu Pecineagu and Surduc. Statistical methods and comparative analyzes of low flow parameters in natural regime and modified regime were mainly used. The results show that the impacts are differents from one case to another. Generally, the flow decrease significantly in modified regime, mainly in spring and summer periods (the breeding period for most aquatic species). This occurs downstream of the reservoirs Surduc, Gilău and Pecineagu. In the case of Siriu reservoir, the impact of the dam construction on the low flow is less significant, and the low flow in modified regime are higher that in natural regime