Mathematical modelling of the Soča River flow in the area of the Plave II power plant outflow
- Authors: Matjaž ČETINA, Mario KRZYK
- Citation: Acta hydrotechnica, vol. 20, no. 33, pp. 329-350, 2002.
- Abstract: Due to the widening of the Soča riverbed near the Hydro Power Plant Plave II outflow, there is a possibility of sedimentation. It is necessary to build a bottom sill just upstream of the outflow in order to redirect the flow of the Soča River in the way that increased velocities near the right bank could flush bed-load and prevent recirculation. A two-dimensional hydraulic computation was applied on the 800 m long Soča River reach. The results of one-dimensional computations and measured water elevations near the temporarily-built flood levee in the vicinity of the HPP Plave II power house were used for the model calibration. At lower discharges of the Soča River (Q = 100, 200 and 300 m3/s), several variants of the proposed bottom sill were investigated. As a final solution, a “broken-line” weir with a lowered crest near the right bank and a hydraulically optimized connection to the bank were suggested. In addition, the high water stages were also investigated. Even when the available sedimentation volume is fully filled with sediment to the weir crest elevation, the water surface elevations near the houses at the left bank just upstream of the weir were not significantly higher at the flood discharge of Q100 = 2718 m3/s.
- Keywords: twodimensional hydrodynamic modelling, PCFLOW2D code, the Soča River, HPP Plave II outflow, bottom sill, bed load transport, sedimentation
- Full text: a33mc.pdf