Urbanizing with or without nature: pollution effects of human activities on water quality of major rivers that drain the Kumasi Metropolis of Ghana
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
Springer
Abstract
The effects of urbanization such as population upsurge, increased industrialization, urban
agriculture, and rural–urban migration of persons
exert pressure on the limited water resources in
most cities. This study investigated the impact of
human activities on the water and sediment quality of the three main rivers (Wiwi, Subin, and Suntre) in Kumasi, the second-largest city in Ghana. The
physicochemical parameters and the concentrations
of contaminants, including heavy metals, polycyclic
aromatic hydrocarbons, pesticide residues, and microbial loads in the rivers, were linked to the specific
human activities at the riverbanks. While all the 37
pesticide residues investigated in river sediments had
concentrations below the detection limits (0.005 mg/kg for organochlorines, 0.010 mg/kg for organophos phates, and 0.010 mg/kg for synthetic pyrethroids),
the study showed that the sediments are polluted with
petrogenic and pyrogenic polycyclic aromatic hydro carbons. River Subin, the most polluted among the
three rivers, recorded benzo[e]pyrene concentrations
up to 47,169 µg/kg. The geoaccumulation index and
concentration factors show that the rivers are highly
contaminated with metals such as cadmium, chromium, mercury, and arsenic and are related to human
activities. The microbial quality of the rivers was
poor, recording specific microbial loads of 6.8, 4.1,
and 1.5× 107
counts/100 mL respectively for Wiwi,
Subin, and the Suntre Rivers. The three water bodies
are therefore not suitable for recreational and irrigational purposes.
Description
Research Article
Keywords
Water pollution, Contamination, Industrialization, Urbanization, Environmental impact, Rural–urban migration