Assessment of the impact of climatic characteristics and landscape changes on the maximum flow of small watersheds

Introduction. The article dedicated to safety of hydraulic structures in small catchments. The research consists in the development of a methodology for assessment of influence of climatic and landscape changes on the maximum flow which determins sizes for the construction elements. The practical significance is due to the assessment of changes in the reliability of hydraulic structures, as well as the degree of potential flooding of territories and soil erosion during rain floods. In scientific terms, the practical significance lies in the justification of changes in the parameters of the formula for the maximum flow calculating. The main goal of the study was to test hypotheses about an increase in the intensity of storm rainfalls and of changes in landscape characteristics during recent decades. Accordingly the next problems were desided: assessment the increase in the daily maximums of precipitation and landscape changes over the past decades; as well as assessing the degree of influence of the above factors on the increase in the maximum water. Materials and methods. The data of the network weather station and the landscape characteristics of the catchment area served as the research materials. Methods of statistical analysis and geoinformation technologies were used as research methods. Results. The main results of the research were the characteristics of the increase in maximum daily precipitation and landscape changes over the past decades and the characteristics of their influence on the increase in maximum water flow, obtained on the base of probability theory and of the surface flow theory. Conclusions. A confirmation of the effectiveness of the proposed methodology for assessing changes in the climatic and landscape characteristics of catchments and their impact on the flood maximums. The hydraulic structures built both in the second half of the twentieth century on small catchments, and in subsequent years when using existing building regulations that do not have proper updating have lost their original reliability.