Hydrogeology of the Skadar Lake basin (Southeast Dinarides) with an assessment of considerable subterranean inflow

Abstract

The Skadar Lake basin is located in the south-eastern part of the classical Dinaric karst region (northern Mediterranean). This region is well known for its highly developed karst and the presence of all types of karstic features. In addition to the high degree of karstification, the advantage of Skadar Lake’s catchment area in terms of water resources is also reflected in the following factors: a large amount of precipitation, scarcity of soil and vegetation cover, favourable geological and geomorphological conditions for karst aquifer discharge, the isolation of the Skadar basin from the influence of the Adriatic Sea and an availability of water for simple abstraction. For the purposes of a more complete determination of the water balance of Skadar Lake, among other undertakings, it has been necessary to determine the groundwater inflow to the lake through numerous sublacustrine springs (vruljas). By using thermal infrared satellite and terrestrial imaging, the locations of the largest sublacustrine springs have been detected and their yield assessed by means of water balance calculation after the application of the KARSTLOP method. The mean annual groundwater inflow to the lake, from the south-western edge only, is 9.86 m3/s. The total outflow of water from the lake through the Bojana River is around 304 m3/s. The coincidence of several important natural factors leads to the large average specific yield (surface and subsurface) in the Skadar Lake catchment area (54 l/s/km2), which makes this region one of the richest areas of freshwater in the world.