Assessment of groundwater impact on water quality in the built-up areas at the Lower Don

Abstract

The impact is assessed that the groundwater flow from the built-up areas on the left bank of the Don River in the Rostov oblast produces on the chemical composition and quality of surface water in the lower river reaches. It is demonstrated that the total average annual groundwater flow from the built-up areas on the left river bank is very small and equals 0.002 km3/year on average or 0.01% of the average annual water flow in the estuarine outlet. Despite the rather high degree of contamination of groundwater and the high content of principal ions, this causes the insignificant impact of groundwater runoff on water quality in the Lower Don. The average total mass of substances that annually come from the left-bank urbanized areas in the groundwater flow is about 4.9 x 10³ t or 0.04% of total mass of substances transported by the Don River to the Taganrog Bay.