Assessment Of Eutrophication Level Of Municipal Surface Water

The level of some nutrient elements in Abuja surface water were investigated for six months to determine the eutrophication profile and make logical inference on the fate of surface water system in the nearest future. Samplings were done monthly for a period of six months covering October to March and standard methods were used for the measurement of some nutrients constituting the indices of eutrophication. The results showed high levels of microbial activities. Biochemical oxygen demand (BOD) showed high levels of pollution which varied with time and velocity of water current. Other parameters investigated were chemical oxygen demand (COD), nitrate concentration, total dissolved solid (TDS), conductivity, algae count, temperature, pH, phosphate and potassium concentrations.

Maximum and minimum values of some eutrophication parameters in the sites were recorded as follows: BOD ( Orozo 38mg/L- 7.37mg/L, Gidan Mangoro 31.2mg/L- 5.08mg/L, Nyanya 32.4mg/L- 10.05mg/L, Wuse 40.30mg/L- 7.007mg/L, Jabi 26.50mg/L- 3.10mg/L). Similarly total dissolved solid maximum and minimum values in the sites were given as Orozo 1222mg/L- 105.1mg/L, Gidan Mangoro 861.0mg/L-148.8mg/L, Nyanya 676.0mg/L- 127.6mg/L, Wuse 200.0mg/L- 86.2mg/L, Jabi 846.0mg/L-151.8mg/L. These results point to eutrophication indicators in Abuja surface water system. The results showed that the concentrations of nitrogen, phosphorus and potassium may be significantly increased beyond their compensation level by the growing human population in Abuja metropolis.