Integrated methods and a complex solution for flood protection and erosion control – A case study of the village of Vrbovce, Slovakia

The aim of the study was an integrated application of methods for the identification and complex assessment of ecosystem responses to abiotic stress factors as extreme runoff, muddy floods and soil erosion processes.  The protection of land with flysch geological structures with regard to and the problems caused by extreme runoff are a very important task in water management. The unsuitable management of land and irresponsible land use causes the formation of flash floods on watersheds and results in accelerated soil erosion. The decreasing soil quality and excessive sedimentation of eroded material in the water structures, which are components of flood protection structures, are a consequence of accelerated soil erosion. Research on and the design of measures were realized on five small watersheds in the cadastral area of the village of Vrbovce, which is situated in western Slovakia, on the edge of the flysch zone of the White Carpathians. Flash floods regularly recur in the village of Vrbovce, and extreme runoff causes the formation of rill erosion on the arable land. The soil erosion was modelled by the Universal Soil Loss Equation and the topographic factor was calculated by the Usle2D program. The results of the calculations show that 96.19 % of the agricultural land is endangered by accelerated soil erosion, with the values of the average annual soil loss greater than the limit for the tolerance of soil erosion. We calculated the direct runoff for five selected watersheds of the Teplica river tributaries with the CN-SCS method. The flooded areas in the village were modelled by the 2D hydrodynamic model MIKE21. A set of measures, i.e., polders, an infiltration trench and agrotechnical measures on the arable land, was designed outside the built-up areas of the village of Vrbovce for the reduction of the extreme runoff and accelerated soil erosion. Measures for the Teplica river revitalisation in the village were proposed. From the estimation of effectiveness of the measures proposed follows that we were able to reduce the amount of the soil erosion to values permissible for the norm by the proposed measures.

Key words: soil erosion, flash floods, flood protection, erosion control and river revitalisation practices