Water Balance and temporal changes of the surface water quality in Xynias basin (SW Thessaly)

Abstract

The study of the Xynias basin is focused on the investigation of the water balance and surface water quality and their impacts due to anthropogenic and natural factors. The average annual precipitation within the study area amounted to 685 mm of which 139 mm (20.3%) is the total runoff, the 428 mm (62.5%) is estimated to be the actual evapotranspiration and 118 mm (17.2%) is the total infiltration. The chemical analyses showed that water flowing from upper reaches of River Enippeas is classified to the Ca-HCO₃ hydrochemical type and it is associated with the presence of limestone’s and flysch formations, while water from the drainage ditch, is classified to the Mg-HCO₃ hydrochemical type and is associated with the development of the ophiolites. The drainage ditch is found to be polluted mainly due to anthropogenic factors.