Abstract

The physicochemical water quality and total coliform density of River Usuma, Abuja, and Nigeria was monitored from July, 2017 to March, 2018. Eighteen (18) physic-chemical parameters were analyzed. Total Coliform assessment gave a mean most probable number value of 174, 68 and 56 (cfu/100ml) for upstream, midstream and downstream respectively. While in the dry season most probable number of coliforms ranging between 9, 6 and 4 were enumerated for upstream, midstream and downstream respectively. Faecal coliform assessment gave a mean value of 180cfu/ml, 175cfu/ml and 187.5cfu/ml in the wet season while 81.3cfu/ml, 62.5cfu/ml and 80.0cfu/ml were recorded in the dry season. Samples taken from the river were subjected to some physicochemical analyses like pH, total alkalinity, electrical conductivity, total dissolved solids, Chloride ion, total hardness, salinity, temperature, nitrate, sulphate, phosphate, total iron, manganese, turbidity, dissolved oxygen, biochemical oxygen demand, and electrical conductivity. The values of pH for both wet and dry seasons (6.6±0.8, 7.80±0.57 respectively), Total alkalinity, electrical conductivity, TDS, salinity, temperature, nitrate, sulphate, phosphate, total chloride, total hardness and BOD were within the WHO, (2006), UNCED (1991) and FEPA (1991) guidelines. While manganese, turbidity, dissolved oxygen organic matter and colour showed exceedance  in UNCED (1992) and FEPA (1991) guiding values for both seasons (<2.0mg/l, < 25NTU, 5.0-7.0mg/l, 2.0-5.0mg/l and 100-200 PtCo respectively). Higher concentrations were obtained for most Physico-chemical parameters in the upstream signifying a high level of influx of organic and inorganic contaminants but buffered by the River’s ability for self-purification. The result showed no significant difference in the Physico-chemical parameters recorded in wet and dry season (P<0.05). Salinity, Sulphate, Phosphate, Iron, Manganese, turbidity, Dissolved oxygen, Organic matter and BOD were significant in all stations sampled (P<0.05).