Assessment of permissible withdrawal of river waters by floodplain fish farms of the Belarusian Polesie

Relevance. The article presents the results of a comprehensive study of the impact on river runoff of the fish farms located in the river floodplains in the Belarusian Polesie. Calculations of hydrological parameters for sections above and below the water extraction sites were performed, cross-sections were constructed. Minimum average monthly water discharges of 95% probability and environmental runoff were determined taking into account the intraannual distribution of runoff of various probabilities. Methods. This study used mathematical method, justification method, geo/ecological method, comparative-descriptive method, and hydrological risk analysis. Results. Mathematical models for river sections were constructed, which make it possible to determine the runoff rates and water discharges, as well as the volumes of permissible water withdrawal from rivers used for the needs of fish farms while ensuring the condition of maintaining environmental runoff in the rivers, depending on the average water depth in the section. Based on operational hydraulic calculations, estimates of the impact of water withdrawal by the studied fish farms on changes in the hydrological regime of water bodies were obtained.