TITLE:
Hydrogeochemical and Biological Evaluation of Packaged Groundwater Sold in Douala City, Cameroon
AUTHORS:
Ma-Effeti Ngale Agbor, Ngwese Sharon Ntube, Aduck Jovens Nyangang, Akoachere Richard Ayuk II
KEYWORDS:
Packaged-Groundwater, Chemical-Quality, Biological-Quality, Cameroon
JOURNAL NAME:
Open Access Library Journal,
Vol.8 No.12,
December
30,
2021
ABSTRACT: Douala is the economic capital of Cameroon situated between latitude 4.00 - 4.15 and longitude 9.65 - 9.95 with an estimated population of over two million and 65,000 households connected to the water supply network. The Douala/Kribi-Campo Basin is a divergent, marginal rift basin and one of the two Atlantic coastal basins of Cameroon, the other being the Rio del Rey Basin. This study evaluates the quality of packaged (Bottled/Sachet/Refilled) groundwater in Douala using hydrogeochemical tools: Gibbs diagrams, Piper diagrams, Durov diagrams, water quality indices and microbial (Coliform Count) analysis. Twenty packaged groundwater samples were sent for chemical and microbial analysis during two seasons. In-situ field measured physicochemical parameters ranged from, pH (5.70 - 8.40), Temperature (11.5°C - 29.2°C); EC (10 - 364 μS/cm) and TDS (6.7 - 243.88 mg/L). The total hardness ranged from 10.07 - 147.15 (mg of CaCO3) soft. Gibb’s diagram indicates the mechanism controlling water chemistry is rock-weathering and atmospheric precipitation. From Durov and Piper diagrams simple dissolution during recharge or mixing is the primary hydrogeochemical process in the evolution of the groundwater chemistry. The groundwater types are CaHCO3 > MgHCO3 with three hydrogeochemical facies in the order [Ca2+-Mg2+- Cl--SO2-4] > [Ca2+-Mg2+-HCO-3] > [Na+-K+-HCO-3]. The WQI is from 6.49 - 38.71 indicating all packaged groundwater in Douala is chemically suitable for consumption. The physicochemical parameters (pH, electrical conductivities, temperature and total dissolved solids) of packaged groundwater are below WHO guideline acceptable limits. From Microbial analysis (Cheesbrough classification), some packaged groundwater were unacceptable (with coliform) in both seasons. The poor quality of the packaged groundwater is considered dangerously unhygienic and thus of great concern. The poor quality of the packaged groundwater is probably due to errors in the processing and packaging of the water. Packaged groundwater actors must have higher quality monitoring control.