Surface water quality degradation in Anambra State, South Eastern Nigeria

Abstract

The study was undertaken to assess the water quality in selected rivers and lake in Anambra State, South Eastern Nigeria. A total of six surface water sources selected(including Rivers Niger,Eziche,Omambala,Obibia,Okpuno stream and Agulu Lake) were from five Local Government Areas in the State, viz.: Onitsha South, Anambra East, Anaocha, Awka North and Awka South. All the samples were analyzed for parameters which include temperature, total dissolved solids (TDS), pH and six heavy metals, viz., As, Cd, Cu, Fe, Pb, and Zn using standard procedures. The results were compared with present National and International (World Health Organisation WHO) standard, the Nigerian Standard for Drinking Water Quality NSDWQ (2007). Among the analyzed samples, all samples contained Zinc and Copper within the NSDWQ (2007), although no guideline is set by WHO (2011) for Zinc level in drinking water. Cadmium , Arsenic , Iron and Lead were above the maximum admissible and desirable limits recommended by NSDWQ (2007) and WHO (2011). Microbiological parameters, viz., total coliform, fecal coliform and the total aerobic heterotrophic bacterial count, were all above the maximum admissible and desirable limits recommended by NSDWQ (2007) and WHO (2011) for all the surface water sources selected. This is an indication of pollution hazards in the study areas, which in turn have important human health implications. In general, the results of the present study have shown that the surface water sources need to be treated before consumption. This study, therefore, recommends the government and other responsible authorities to take appropriate corrective measures.