Status: this discussion paper is a preprint. It has been under review for the journal Natural Hazards and Earth System Sciences (NHESS). The manuscript was not accepted for further review after discussion.
The catastrophe of the Niedów dam – the dam break causes,
development and consequences
Institute of Metheorology and Hydrology and Water Management – National Research Institute
Abstract. Due to extreme rainfalls in 2010 in the Lusatian Neisse river catchment, a ﬂood event with a return period of over 100 years took place leading to the failure of the Niedów dam. The earth type dam was washed away with a result of a rapid release of nearly 8.5 million m3 of water volume and ﬂooding of the downstream area with substantial material losses. The paper analyses the conditions and causes of the dam’s failure, while special attention is given to the mechanism and dynamics of the compound breaching process. Several empirical formulas for the dam breach prediction are tested with regards to their usefulness in assessing breach dimensions and outﬂow peak discharge. The paper also describes a numerical approach to simulate the ﬂood propagation downstream the dam with the use of a two-dimensional hydrodynamic model. Considering the speciﬁc local conditions and available data set, an iterative, reversed solution of the unsteady state problem is made. This approach enabled to deliver realistic ﬂood propagation estimates, veriﬁcation of the dam breach outﬂow, and several important answers on the dam failure consequences.
How to cite. Kostecki, S. and Banasiak, R.: The catastrophe of the Niedów dam – the dam break causes,
development and consequences, Nat. Hazards Earth Syst. Sci. Discuss. [preprint], https://doi.org/10.5194/nhess-2020-372, 2020.
Received: 02 Nov 2020 – Discussion started: 23 Nov 2020
The Niedów dam failure caused by an extreme flood event is described. A special emphasis is put on explaining the compound dam break mechanism, its dynamics and resulting outflow from the reservoir, leading to flooding over an extended downstream area. The flood wave propagation in a complex hydrological system is resolved with the use of hydrodynamic 2D modelling. The current prediction formulas for the dam break are also tested and discussed on their performance and usefulness.
The Niedów dam failure caused by an extreme flood event is described. A special emphasis is put...