Development of a procedure for assessing the environmental risk of the surface water status deterioration

A procedure for estimation of the risk of violation of the water body status was presented. The procedure is based on defining environmental standards of surface water quality taking into account landscape and geographical features of river basins. A database of the systems of monitoring surface water was used to assess the risk of deterioration of the aquatic ecosystem. This enables automated calculation of the environmental risk. At the first stage, it is necessary to determine environmental standards (ES) on the basis of analysis and statistical processing of long-term monitoring data on the qualitative state and hydrological regime taking into account forecasting models. At the second stage, probability of violation of ecological standards is estimated by the ratio of the number of observations of the ecological state of the water body with violation of the ES to the total number of observations. Exceeding environmental standards makes it possible to assess the risk of well-being violation in aquatic ecosystems. Assessment of the environmental risk of deterioration of Udy River and Oskil River in Kharkiv region, Ukraine, has made it possible to make the list of priority pollutants and outline the main problems for which a complex of environmental measures should be worked out. Establishment of the risk of well-being violation in the aquatic ecosystem will contribute to the implementation of a flexible system for regulating water quality taking into account ever-changing socio-economic and environmental conditions. The proposed procedure for assessing the environmental risk of deterioration of the status of aquatic ecosystems is based on the normative basis, approaches and methods of environmental assessment of surface waters adopted in Ukraine and the EU