Physicochemical and bacteriological characteristics of groundwater in Rumuigbo, Obiokpor Local Government Area of Rivers State, Nigeria

Abstract

Water is one of the most important and abundant compounds on earth, and it is vital to the survival of all life forms. Groundwater is the most utilized in the southern part of Nigeria. Many groundwater extraction boreholes exist in Rumuigbo, Obio-Akpor Local Government Area of Rivers State, Nigeria. This study was carried out to assess the physicochemical and bacteriological characteristics of groundwater in the communities within Rumuigbo. Water samples were collected from groundwater extraction boreholes in the four communities within Rumuigbo: Omoi/Orosi, Nkpolu, Mgbuadu, and Mgbu-Esilaru. The samples were analyzed for Electrical conductivity (EC), salinity, pH, turbidity, nitrate, phosphate, iron, lead, zinc, total heterotrophic bacterial population (THBP), Vibrio, Shigella, and Salmonella populations using standard physicochemical and bacteriological methods. The results showed that EC of the groundwater in the four communities was 3.74±0.38 to 17.08±1.03 μS/cm; salinity was 1.02±0.01 to 1.66±0.54 mg/L; pH was 5.94±0.01 to 6.95±0.23; turbidity was 0.04±0.01 to 0.05±0.02 NTU; nitrate was 0.46±0.06 to 0.71±0.02 mg/L; phosphate was 2.85±0.03 to 3.34±0.15 mg/L; iron was 2.34±0.55 to 6.74±0.08 mg/L; lead was 0.18±0.04 to 0.40±0.14 mg/L; and zinc was 0.40±0.06 to 3.91±0.13 mg/L; THBP was 1.8±2.6 to 3.4±3.2 ×102 CFU/ml. There were no Vibrio and Shigella in the groundwater samples, except in one sampling point in the Mgbu-Esilaru and Mgbu-adu communities, respectively. The bacteria identified include Proteus, Bacillus, Micrococcus, Pseudomonas, Salmonella, Erythrobacter, and Klebsiella species. It is revealed that groundwater from the communities fulfills some of the requirements for portable drinking water but does not meet the standards for iron, lead, zinc, and Salmonella. Some form of groundwater treatment from the communities is required to meet all the requirements for potable drinking water.