ОЦЕНКА ПОГРЕШНОСТИ РАСЧЕТОВ МАКСИМАЛЬНОГО СТОКА МАЛЫХ РЕК

Abstract

The share of the studied small watercourses on the territory of the Russian Federation is 0.01% of their total number. In this regard, when conducting hydrological calculations for the vast majority of projected structures, especially linear ones, the surveyor deals with unexplored rivers. To design and ensure safety in the operation of various water management and hydraulic structures on water bodies, it is recommended to use the Set of Rules SP 33-101-2003 and methodological recommendations for determining the calculated hydrological characteristics in the absence of hydrometric observations. However, until now, a full-fledged analysis of the error in calculating the values of the maximum runoff of a given repeatability according to the methods proposed in the joint venture, in comparison with the observed ones, has not been carried out. The proposed work fills this gap for streams (catchment areas <1 km2) and small rivers (up to 2,000 km2) in the forest zone of the European part of the Russian Federation. Before calculations, the necessary preliminary analysis of the initial observation data on the analogous rivers was carried out in order to assess the quality of the initial hydrometeorological information. The calculation of the maximum water flow rates of streams and small rivers of spring flood is considered using the reduction formula. The maximum urgent water flow rates of rain floods of a given probability were calculated using: the type I reduction formula in the presence of one or more analogous rivers; the type II calculation formula in the absence of analogous rivers; and the type III limit intensity formula. One of the calculation option is considered according to the type I formula when using various analogues that meet the requirements of the joint venture for such. As a result of calculations, it is concluded that for streams and rivers with a catchment area of up to 100 km2, the discrepancy in the values of the measured and calculated 1% of the spring flood flow rate can reach 300%, and rain floods – 2,000%. Such an error in any case can not ensure the safety of the operation of the designed structures