Hygienic aspects of using the resources of small rivers of the Volga region for drinking water supply on the example of the Saratov region

Abstract

The transformations in the environment occur both under the influence of natural processes and anthropogenic influences. Small rivers are one of the most vulnerable to changes in natural objects. Wastewater is a specific source of pollution for reservoirs: the most frequent pollution of small rivers is caused by flushing from agricultural land. The lower Volga region belongs to regions with unfavorable conditions for water supply, which is caused by a complex of natural and anthropogenic factors. The Saratov region by its geographical location, climate conditions, level of development of socio-economic relations, features of agricultural production largely reflects the regional characteristics of the Lower Volga region and can serve as a model for making management decisions to improve the hygienic conditions of water supply in rural areas of this region. Analysis of the results of laboratory studies, as well as sanitary and topographical study of the coastal zone indicates insufficient implementation of water protection measures on the researched rivers: they are mainly cosmetic in nature and do not contribute to a radical improvement of the sanitary and ecological situation on small rivers. Given the excess of water quality indicators in the flood period, also in the summer, the water of the Nahoy and B. Karaman rivers can be attributed to the second class of water supply sources, which implies the need to clean and disinfect water from these reservoirs when using it for drinking purposes. Values of the total hazard index for small rivers showed a clear seasonal relationship: for samples taken in the summer, they were higher than for samples taken in the spring. The value of non-carcinogenic risk exceeded the acceptable value for all samples, while the greatest contribution to the probability value of risk is made by nitrites, nitrates, iron and manganese, as typical surface water pollutants of arid zone water.