Storm water pollution in the urban environment of Vilnius, Lithuania

Abstract

Wastewater – it is precipitation on the surface of urban areas and other waters. Wastewater flow rates varies depending on the time of year and weather conditions, and their contamination depends on industrial and urban development, transport development, human economic activity. Because of the increasing pollution of surface wastewater bodies, the eutrophication process is intensified. Suspended solids trapped in surface waters can lead to physical (reduced light penetration, changes in water body temperature, sludge formation), chemical (emission of heavy metals, nutrients and pesticide during adsorption to the surface waters from formed sediments) and biological (decrease of dissolved oxygen quantity in the surface water body) changes in water bodies. Therefore, it is necessary to investigate the concentrations and dynamic changes of untreated sewage entering the surface water bodies. After these tests the most pressing areas of pollutants are found where installation of wasterwater treatment facilities is needed. The article analyses the pollution indicators of surface wastewater that is generated in the urban area in the northern part of Vilnius city. These parameters were explored: BDS5, total nitrogen, total carbon, oil products, suspended solids, pH, amount of dissolved oxygen and temperature.