Influence of discharged industrial effluents on the parameters of surface water in Onitsha urban area, southeastern Nigeria

• Published in: Journal of water and land development 2019-09, Vol.42 (1), p.136-142
• Main Authors: Obeta, Michael C., Okafor, Uchenna P., Nwankwo, Cletus F.
• Format: Article
• Language: English
• Subjects: Biochemical oxygen demand; Calcium; Chemical industry; Chemical oxygen demand; Chromium; Chutes; Coliforms; Copper; Discharge; Dissolved oxygen; Drinking water; drinking water supplies; E coli; Effluents; Households; Industrial effluents; Industrial wastes; Industrial wastewater; Industry; Organic chemistry; Oxygen; Parameters; Pollution effects; Rivers; Stream pollution; Streams; streams contamination; Surface water; Total dissolved solids; Total oxygen demand; Turbidity; Urban areas; Wastewater disposal; Wastewater treatment; Water analysis; Water pollution; Water quality; Water sampling; Zinc
• ISSN: 2083-4535; 1429-7426; 2083-4535
• DOI: 10.2478/jwld-2019-0054

Chemical industries in Onitsha urban area of southeastern Nigeria have been discharging large quantities of effluents into surface streams. These streams are the primary sources of water used by poor households for domestic purposes. This study examines the effects of effluents on the physicochemical and microbiological characteristics of the recipient streams. This objective was achieved by collecting eight effluents and twenty-two water samples from control points, discharge locations and exit chutes of the effluents for analysis. The results of the study characterised the effluents and their effects on the recipient streams. The effluents cause gross pollution of the streams as most of the parameters including pH, total dissolved solids (TDS), turbidity, biological oxygen demand (BOD), chemical oxygen demand (COD), Mg, NO , Fe, Cu, Pb, Cr, total heterotrophic count (THC) and total coliform group (TCG) returned high values that exceeded the World Health Organisation’s (WHO) benchmark from 2011 for drinking water quality. Only dissolved oxygen (DO), Na, Zn, Ca, and Na returned values lower than the WHO guideline. was found in all the samples; TCG was also high. This paper, therefore, recommends that the effluent generating industries should treat their effluents before disposal.