A DYNAMIC-STOCHASTIC APPROACH TO THE DETERMINATION OF THE OPTIMUM LEVEL FOR RESERVOIR FILLING
Keywords:
Aral Sea, water balance, dynamic-stochastic approach, hydraulic structure, reconstruction, reservoirAbstract
Possessing certain information and knowledge about the current hydrological state of a water body, it is possible to foresee the future state of the studied object and its main characteristics. On their basis it is possible to estimate the peculiarities of the given period and to carry out corresponding to these conditions the development of effective regimes of functioning of hydraulic structures with advance or mitigation of the onset of hydrological threats and risks.
The condition for optimal functioning of natural ecosystems is a close relationship between fluctuations in water levels and river and sea runoff - this is the specificity of the study of water bodies in the Aral Sea region.
The proposed work evaluates the reconstruction options for the Northern (Small) Aral Sea. To determine the quantitative characteristics of the parameters of the object under study (Northern Aral Sea - Saryshyganak Bay), the balance method was used by means of sequential solution of balance equations that allow indirectly assessing its dynamics, hydrological state and analysing the interrelationships of various components of the moisture balance.
Based on the dynamic-stochastic approach in solving the problems of determining the optimal level of filling of the retaining hydraulic structure, where in the balance calculations a temporary hydrological series (n > 35) made up of annual river inflow volumes by the method of statistical modelling (Monte Carlo method) is used, it can be concluded that out of two variants of the complex of considered engineering structures in the water area of the Northern Aral Sea, the most preferable is the variant of reconstruction of the NAS with the mark of the normal retaining level. The two-level variant of the reconstruction corresponds to the optimal parameters of the structure with a short period of filling of the bay 6-7 years, less water losses - up to 3.0 km3 and moderate the system water exchange processes.
