TITLE:
Potential Impact of Wash Bay Effluent on the Water Quality of a Subtropical River
AUTHORS:
Concilia Danha, Beaven Utete, Gabriel Soropa, Simbarashe B. Rufasha
KEYWORDS:
Hydrocarbon, Impact, Pollution, River Integrity, Self-Purification
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.11,
August
20,
2014
ABSTRACT: Washbay effluents have received scant attention as a potential source of
water pollution globally. This study is the first to investigate the potential
impact of the total wash bay effluent content released into river water in
Africa. We investigated the potential ramifications of wash bay effluxent released
off Charter Estates, Chimanimani in the Eastern Highlands of Zimbabwe on the
water quality of the receiving subtropical Nyahode River by measuring selected
water limnochemical aspects which included biological oxygen demand (BOD),
chemical oxygen demand (COD), oil and grease, pH, sulphates, phosphates, iron,
total suspended solids (TSS), dissolved oxygen (DO) and electrical conductivity
(EC) once every 3 months from October 2011 to July 2012. The obtained mean
levels of the limnochemical parameters from the Nyahode River were compared to
the local Environmental Management Agency (EMA) and international World Health
Organisation (WHO) effluent standards. Our results show that the control point
and the off effluent discharge source downstream points in the Nyahode River
had water quality parameters that were below the local EMA and WHO water
quality threshold values. Cluster analysis showed a strong linkage in the
values of water quality parameters measured at sampling sites 3 and 4 which
were below the discharge point. Wash bay effluent released from the Charter
Estate has an impact on some aspects of the water in the Nyahode River but the
river has a functional self-purification capacity. Onsite industrial
purification of wash bay effluent before discharge reduces its potential
deleterious impact on water quality, river habitat integrity and aquatic
biodiversity.