Physico-chemical analysis of Logone River water at Moundou City in Southern Chad

Abstract

The physico-chemical parameters and some heavy metal concentrations in the Logone River water at Moundou City, Chad, are studied for two stations from July 2013 to December 2014, one upstream and another downstream of the city. Standard methods are used. A total of twenty-two physico-chemical parameters were determined by spectrophotometers showed clear seasonal variations of; BOD5, COD, sulphate, phosphate, and nitrate, among the stations. The Moundou City wastewater negatively impacted the concentrations of physicochemical parameters of Logone River water samples when compared with the World Health Organization (WHO) permissible limits. It was observed that the water quality parameters exceed the permissible limits downstream of the river:BOD5 (198mg/l), COD (897 mg/l), MES (287 mg/l), F(1.87 mg/l), heavy metals Cr (0,934 mg/l), Fe (5,55 mg/l) Cu (0,294 mg/l), Pb (17 mg/l), As (0,894 mg/l), Mb (14,2 mg/l). This study shows that industrial discharge into Logone River seriously contributes to the pollution of the river at the level which poses health and environmental hazards to those using it in downstream for domestic and agricultural purposes.

Keywords: Heavy metals, river water pollution, physico-chemical properties, Logone river, Moundou, Chad.