Assessment of hydrological drought in the north-eastern part of Romania

Abstract

On the background of amplification of hydro-climatic drought in the last decades, in this paper we try to evaluate a series of indexes for assessing hydrological droughts. To characterize the hydrological drought, minimum flow parameters are successively analyzed: percentiles from the flow duration curve, mean annual minimum flow, base flow index and recession indeces. Also was used some indices to evaluate the water deficit from streams like thereshold level method and the sequent peak algorithm. Each method was exemplified using data from hydrometric stations from Bahlui drainage basin and associated data from 2012 summer drought. The results show that in the 2002-2014 period, the average drought duration of the cold season is 23 days, but with a low water deficit due to conditions of quartering it in the form of ice and snow layer. In summer season, the average lenght of hydrological drought is 22 days, with a huge water deficit which may exceed 37.5 mil. m3 as happened in the summer of 2012.

Keywords

• hydrological drought
• indices
• water deficit
• Bahlui drainage basin