Maximum flow variability and floods characteristics in the Central and North Dobrogea

Abstract

A deep knowledge of the maximum flow is required to build the hydraulic structures, to assure a good water management and, especially, to prepare an efficient flood defence. This paper aims to analyze the maximum flow and the floods characteristics from the Central and North Dobrogea. The physico – geographical factors which influence the water resources from the studied area are: the climatic conditions, the geological conditions, fhe forest coverage and the loam – clay soils. The analysis is based on the processing of the annual and monthly discharge of 11 hydrometric stations (with observation periods which ranged between 24 and 55 years). The frequency and the characteristics of the 61 floods have been identified. The values of the maximum annual discharge ranged between 12.2 and 488 m³/s. These values exceeded the values of the maximum discharge with the probability of 0.01% (Slava River), 0.1% (Teliţa River), 0.5% (Hamangia and Cartal Rivers), 3% (Topolog, Taiţa and Râmnic Rivers) and 5% (Casimcea River). An important feature of the maximum flow, from the studied area, is highlighted by the fast character of the floods. These have a total duration which ranged between 6 hours and 47 hours and an increasing time which ranged between 2 hours and 12 hours. The analyzed floods are common, mainly, between May and September highlighting their exclusively pluvial origin.