Impact of discharge wastewater effluents on the physico-chemical qualities of a receiving watershed in a typical rural community|
Igbinosa, E. O. & Okoh, A. I.
The qualities of the treated final effluents of a wastewater treatment plant located in a rural community of the Eastern Cape Province of South Africa were assessed over the duration of 12 months. Parameters measured include pH, temperature, electrical conductivity, salinity, turbidity, total dissolved solid, dissolved oxygen, chemical oxygen demand , nitrate, nitrite and orthophosphate levels and these were simultaneously monitored in the treated final effluents and the receiving watersheds using standard methods. Unacceptably, high levels of the assayed parameters were observed in many cases for chemical oxygen demand (7.5-248.5 mg/L), nitrate (1.82-13.14 mg/L), nitrite (0.09-1.3 mg/L), orthophosphate (0.07 - 4.81 mg/L), dissolved oxygen (4.15-11.22 mg/L) and turbidity (3.68-159.06 NTU) during the study period and are severally outside the compliance levels of the South African Guidelines and World Health Organization tolerance limits for effluents intended for discharge through public sewers into receiving watersheds. The study has revealed that there was an adverse impact on the physico-chemical characteristics of the receiving watershed as a result of the discharge of inadequately treated effluents from the wastewater treatment facility. This poses a health risk to several rural communities which rely on the receiving water bodies primarily as their sources of domestic water. There is need for the intervention of appropriate regulatory agencies to ensure production of high quality treated final effluents by wastewater treatment facilities in rural communities of South Africa.
Orthophosphate, nitrate, chemical oxygen demand, dissolved oxygen, conductivity, total dissolved solid