Modern problems in assessment of hydraulic resistance

The paper is devoted to the analysis of modern problems in assessment of hydraulic resistance. The obtained formulas for calculating the roughness coefficients and other interrelated hydraulic parameters of the channel are given. As a determining factor for the systemic characteristics of flows, N.A. Rzhanitsyn used the average long-term and average maximum water discharges, and the authors of this work proposed the use of these characteristics in accordance with the watershed area A in km2 of the subsequently derived dependences for unexplored rivers. Thanks to this approach, it became possible to obtain information by cartographic methods. Direct approximation of these data gives an expression for the flow order. The formulas obtained can be used to calculate the hydraulic characteristics of lowland rivers. For the European territory of Russia, the formulas have been tested using independent field information. However, the authors believe that the formulas will successfully work for other even lands as well. The formulas are simple and easy to calculate using software. In the future, it is planned to use specialized software for processing calculations and use the obtained results in the geographic information system.