Significant variability characterizes natural streams in space and time that describe hydraulic regime of the entire stream. In this paper, the importance of investigation and assessment of hydraulic system in the context of management of surface water resources is discussed. The objective of this study is to investigate hydraulic regime in the middle part of Loire River located in France. Loire River basin is the largest river basin in France and origin of many potential flood events. Investigation of a hydraulic regime of the Loire River is conducted using traditional hydraulic simulation model HEC-RAS. Hydraulic modeling of the river is carried out by considering two different datasets (i.e. flood and low flow events). A certain number of hydraulic structures, which have the significant effect on the hydraulic regime of the river, is considered as well. Through Froude number computation, it is noticed that middle part of the Loire River demonstrates subcritical regime. Accurate calibration and validation of the model are performed by changing Manning coefficient along the riverbed. Computation carried out for both data sets; show that there are no big differences between observed and simulated water levels, results obtained are satisfactory. Therefore, to get more accurate information about the hydraulic regime at the middle part at of Loire River, the further simulation needs to be done by considering an additional dataset of floods and low flow events.
Authors:Alban Kuriqi, Mehmet Ardiçlioglu and Ylber Muceku
World experiences reveal that catastrophic floods are posing a serious threat that comes not only from them as extreme events but also as the result of adaptation measures uncertainty, (i.e. dikes). In particularly old dikes constructed earliest at the north part of Albania, during the last floods demonstrated the high uncertainty and weak spots. In this paper, the significance of the seepage investigation and stability analysis are discussed. As a case study, parts of new dikes constructed last years along the Buna River located in north part of Albania are investigated. Filling materials for these dikes are represented mostly from silt and clay. Finite element method is used to perform seepage analysis while general limit equilibrium method is used to perform slope stability analysis. Both, seepage and slope stability analyses are done for three different scenarios: steady state, rapid filling, and rapid drawdown. Finally, it is concluded that silt-clay material used in these dike structure is posing serious uncertainty during seepage phenomenon by threatening the stability of entire dike structure especially during the transient condition (rapid filling and drawdown).