Evaluation of Water Quality within and around Flood Prone area and Dumpsite Environment in Part of Benin Metropolitan city Southern, Nigeria

Abstract

The study was carried out in Egor local government area, Dumpsite in Ovia North-East local government area of Edo state. The study areas are located between latitudes of 6°27'27.8''N to 6°27'44.6''N and longitudes of 5°35'58.7″E to 5°36'16.8''E in Egor local government area and the dumpsite is located with a latitude of 6°22´1.2''N to 6°27´51.3″N and longitudes of 5°36'42.3''E to 5°36´2.1″E in Ovia North-East local government area. A total of five (5) water samples were collected from an existing borehole at different locations within the study area. Physiochemical test, Major anion and cation concentration was determined using Atomic Absorption Spectrophotometer (AAS). Microbiological Parameters for all the water samples was also determined. The following are the physiochemical parameters, major cations and anions that was analysed from all the water samples collected: pH, EC, TDS, Na+, Ca+, Mg2+, Cl-, NO3- , HNO3- , HNO3- , SO42- , Cr2-, Cd-, Ni-, and Pb2+ and the Microbiological parameter analysed for all the water samples are Coliform and E. Coli. The Microbiological parameter analysed for are Coliform and E. Coli as shown in Table 1. The results reveals that the study areas have average value of pH (4.89) which is below the WHO (2011) and NSQW (2007) standard permissible limit of 6.5-8.5 and this indicates that the water is slightly acidic probably due to the presence of decayed organic matter in high amounts and mineral acids produced during hydrolysis. The average values of E.C (121.86μS/cm), TDS (46.52mg/l), Na+ (1.48mg/l), Cl- (53.85mg/l), NO3- (1.17mg/l), HNO3- (0.39mg/l), SO42- (0.12mg/l), Cr2- (0.031), and Ni- (0.0074) conforms with the WHO (2011) and NSQW (2007) standard for drinking water expect some physiochemical parameters : Ca2+, Mg2+ Cd-, Pb2+, E.Coli and Coliform which has average values (4.49mg/l, 3.10mg/l, 0.027mg/l, 0.016mg/l, 1.36 X 103 (cfu/100mL)and 1.06 X 103 (cfu/mL) which do not conform with the WHO (2011) and NSQW (2007) for drinking water because of many factors and anthropogenic activities on the environment which contaminated the groundwater of the study areas. The results analysed from the three-study area reveals that the physiochemical parameters and microbiological parameters show similar trend. The water sample collected in the premises of University of Benin is more acidic compare to other water samples from the other locations. This probably due to the presence of decayed organic matter in high amounts and mineral acids produced during hydrolysis.