The health-related microbial quality of drinking water from ground tanks, standpipes and community tankers at source and point-of-use in eThekwini Municipality : implications of storage containers, household demographics, socio-economic issues, hygiene and sanitation practices on drinking water quality and health.

Abstract

The aim of this study was to investigate the microbiological quality of drinking water at the

source (taps at eThekwini laboratories, standpipes and mobile community tankers) and

corresponding point-of-use (storage containers and ground tanks) supplied to peri-urban areas

in Durban by eThekwini Municipality. It also aimed to identify factors associated with

deterioration in water quality such as storage of water, household demographics, hygiene and

sanitation practices. In order to determine the microbial quality of drinking water, the pour

plate method (for enumeration of heterotrophic organisms) and the membrane filtration

technique (for total coliforms and E. coli enumeration) were used. Conductivity, turbidity, pH

and total and residual chlorine levels of drinking water were measured. Microbial and

physico-chemical data was collated and statistically analysed with epidemiological data from

an associated study to determine the link between microbial quality of drinking water,

household demographics, health outcomes, socio-economic status, hygiene and sanitation

practices. Findings showed that all point-of-use water was unsafe for human consumption as

a result of either poor source water quality, in the case of standpipes, and microbial

contamination at the point-of-use, in the case of ground tanks and community tankers. The

latter could be attributed to unsanitary environments, poor hygiene practices or poor wateruse

behaviour. Households which included children aged 0-5 years and in which open-top

containers were used for water storage had the highest rates of diarrhoea and vomiting. Water

from ground tanks had the best microbial quality but people in households using this water

presented with the highest rate of diarrhoea. Therefore provision of microbially safe drinking

water will not reduce the rate of health outcomes if addressed in isolation. In order to reduce

water-associated illness, provision of safe and adequate amounts of water, hygiene and

sanitation education and education on water-use behaviour should be provided as a package.

The provision of improved water delivery systems does not ensure that drinking water is safe

for human consumption. Measures, such as point-of-use water treatment should be

considered to ensure that drinking water provided at the source and point-of-use is

microbially safe for human consumption.