Geoscience Reference
In-Depth Information
The computations presented in Fig.
5
, as well as the other simulation results
(flow velocities, flood wave front propagation speed, and time of water arrival)
estimated for the several variants of the reservoir embankment breaking were used
by the ENERGA Elektrownie Straszyn Ltd. (an owner and operator of the Bielkowo
hydropower plant) to create the flood risk maps. The maps have been used by the
Gda
´
sk Board of Water Management and the Disaster Recovery Center to manage
the flood risk in the Gda
´
sk region.
5 Conclusion
Numerical simulation of the dam breaching and the catastrophic flood are important
for reducing threats due to potential reservoir embankments failures. The results of
hypothetical flood simulation after the Kolbudy II reservoir embankment break
prove that the two-dimensional Saint-Venant model is a proper solution to analyze
the spatial pattern of the risk of flooding. The model provides information about
depth and duration of inundation as well as velocities and direction of water flow.
These parameters combined with the information about inhabitants number and
buildings construction and value can give an approximation of flood risk.
The Bielkowo hydropower plant is one of the eight power plants located on the
Radunia River. Considering the cascade form of the Radunia hydropower system,
the mathematical modeling of flood routing along whole Radunia River valley is
necessary to manage the flood risk in this region. The need of the complex analysis
of the flooding after collapse of one of the hydropower plants is a result of danger of
failure of the next dam due to overflowing. The extreme flood following the failure
of the first dam could damage some hydrostructures along the cascade increasing
the flood hazard in the river valley. Such a situation should be simulated and the
complex catastrophic flood risk maps for the Radunia catchment ought to be
elaborated. At this moment the possibility of flood analysis for the Radunia
catchment is limited due to incomplete DEM of the catchment area and poor
reservoirs bathymetry data.
Acknowledgments This chapter presents some results obtained in the project “A mathematical
model of the hydraulic effects of the Bielkowo hydropower derivation channel embankments
breaks and Kolbudy II reservoir dams failures,” which has been financed by the ENERGA
Elektrownie Straszyn, ul. Hoffmanna 5, 83-010 Straszyn, Poland.
References
Abbott MB (1979) Computational hydraulics: elements of the theory of free-surface flows. Pitman,
London, pp 324
Jarz˛bi´ska T (2005) Hydraulic power plants on the Radunia River. In: Open channels flows in
view of water framework directive. Proceedings of XXV International School of Hydraulics,
Institute of Hydro-Engineering of the Polish Academy of Sciences, Gda´sk
