ИСТИНА

Аbstract River pollution is the crucial environmental problem in water management. This problem is particulary important for the transboundary rivers, and a striking example comes from Ural River basin. The Ural River basin (ext. 236000 km2) is located on the territory, which is limited by 54°46' NL on north, 41°15' NL on south, 46°30' EL on west and 60°44' EL on east. Ural River is 2428 km at length. It marks the border between Europe and Asia. Ural river flows southward from mid latitudes to the Caspian Sea. The Ural River is transboundary river for Russia and Kazakhstan. Basin area is divided between these countries in 52,8 and 47,2 %. Some inflows are forming at Kazakhstan territory and flows to the Ural River in Russia. Water resources of the river (annual runoff is 12,6 km3) originates within Russian part of the catchment. Ural River’s water resources system faces various water quality problems. Decline in water quality is mostly due to water use within both Russia and Kazakhstan. The chemical composition of the rivers of the basin is defined as the ratio of the original genetic types of waters formed in the catchment area and the different phases of the water regime and significant anthropogenic impacts. Copper, iron, total nitrite ion and BOD5 values exceed the permissible levels accepted in Russian Federation. Another important problem in water quality control is absence of the unified water quality assessment system applied in adjacent countries.