Groundwater quality and risk of pollution from natural, human and urban transport activities in the Drini basin

Abstract

Groundwater quality study was conducted in the Drini basin situated in the northern part of the Albanian territory. The objective of this study was to identify the quality of groundwater in four different well-defined monitoring sites. Groundwater is vital for the population and is considered to be subject to continuous exploitation with high growth intensity, and permanent risk of pollution from natural and human activities. Contamination of groundwater occurs when synthetic products such as gasoline, oil, road salts and chemicals get into the groundwater and return it unsafe and unfit for human use. Groundwater monitoring was carried out according to a network, which aimed to include mainly the most intensive areas of exploitation and distribution in the aquifer. Samples were collected in two different months of June and October in four monitoring drilling sites and were analysed for those key indicators defined by the rules and procedures for the drafting and implementation of the national programme of environmental monitoring in Albania. The study results reveal that geological formation, human activities as well as environmental conditions affect groundwater quality. Complete chemical analysis revealed that the groundwater in this area results in medium hardness, has good physico-chemical properties, local pollution is encountered, and there is no massive pollution of the basin. They are waters with low mineralisation. Further, they are neutral waters, which meet the allowed norm for drinking water. The pollution displayed is occasional, as the presence of NH4+ and NO2- are isolated cases, manifested mainly by the non-application of areas of strictness and sanitary protection around the drill and the small cover of the subaxillary layer. The analysis performed for microelements shows that the content of some heavy metals is below the maximum allowed amount; this demands serious future attention to the density of the network and the monitoring frequency in this basin. The risk of pollution in the Drini basin is high due to the small protective cover, especially in the source of Dobrac. Intensive exploitation can lead to the mixing of fresh water with water with high mineralisation. The concentration of Cu, Pb, Zn, Cr, Cd, Na+, K+ and Cl− in the water samples known as the major pollutants from the urban transport sector, has shown that the values are within the water quality standard. The low concentration of these pollutants was due to the distance of the drilling sites from the roads in these areas.