Summary:
. Altinapa Dam which is located on Meram Stream (also known as Dolay Stream) in Konya Province supplies drinking water. The Altinapa dam feeds the Konya Drinking Water Treatment Plant with 37.8 million m3 of water annually and the treated water is delivered by the drinking water network. The aim of this study is to determine the effect of agricultural activities and settlements on water quality in Altınapa Watershed. In the study, major water quality parameters (pH, electrical conductivity, total organic carbon, total nitrogen, nitrite, nitrate, phosphorus, phosphate, and total suspended solids) and pesticides were included in the scope of monitoring at four points (K1, K2, K3, K4) on the sub-streams feeding Altinapa Dam. Major water quality parameters were monitored for 12 months between June 2020 and May 2021, and pesticides were monitored for 4 periods seasonally (September 2019, January 2020, August 2020, and April 2021). A correlation matrix was used to assess the connections between nine indicators of water quality. The annual average conductivity and pH values of the samples taken from 4 different points of the Meram Stream that feeds the Altinapa Dam are 432 µS/cm and 8.04, respectively. The highest value for total nitrogen was 10.73 mg/L and it was .87 mg/L for nitrate. Annual average TOC values were determined as 1.35, 1.69, 1.51 and 1.46 mg/L at K1, K2, K3 and K4 points, respectively. Specific UV absorbance indicated that organic matters of water are mostly hydrophilic and low aromatic content. In seasonal pesticide monitoring, 71 different compounds were screened in water samples. Compounds exceeding Turkish Environmental Quality Standards were identified as DDD-op, DDE-p.p', diflufenican, and imidacloprid. Pesticides constitute most of the micropollutants detected in water samples. The highest positive correlation among water quality parameters was obtained between conductivity and nitrate (0.81) and total nitrogen (0.88).