Evaluation of spatio-temporal variations in microbial pollution indicators of a river passing through lowlands and urban areas in Northern Türkiye

Abstract

The degradation of watersheds due to urban development increases the vulnerability of surface waters to pollutants of anthropogenic origin. Urban streams draining near swimming waters can contribute significantly to the deterioration of water quality. In the study, the microbial quality of the Terme River was investigated seasonally by collecting samples from four different stream sites. Microbiological analyzes were performed using standard methods with membrane filtration. The colony-forming unit (CFU) method determined fecal contamination in samples. The mean number of colonies in Terme River water samples was determined as 712 CFU/100 mL, 278 CFU/100 mL, and 64 CFU/100 mL for total coliform, Escherichia coli, and Clostridium perfringens, respectively. This situation indicates that there was fecal contamination in the stream. According to the bacteriological parameters in the Water Pollution Control Regulation, Terme River was found to be of class II water quality in terms of total coliform bacteria count. The Research results determined that the Terme River is not much polluted in terms of microbiological quality but has values under the pressure of pollution. To not increase the pollution level, the direct mixing of domestic wastes/wastewater, animal wastes, and drainage channels from the settlements and agricultural areas around the river should be prevented. The public should be made aware of the necessary precautions.