Transcript Dr Jo Barnes ,University of Stellenbosch

Point of Use Water Systems:
Solutions that meet water quality
challenges
Jo Barnes
Division of Community Health
Faculty of Medicine and Health Sciences
University of Stellenbosch
Tygerberg
Policy Dialogue: DST/EU Sector Budget Support, HSRC and the WRC
2 October 2012
Some questionable assumptions
Two broad categories of users of POU devices in
South Africa - the well-off and the poor:
 Well off people only use POU devices to improve water
taste (or are neurotic about health)
 Poor people use (need?) POU devices to make water safe
REALITY There is wide overlap of reasons for use distributed
over many income classes.
So-called high income families do not necessarily
have access to safe, acceptable water
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Some questionable assumptions
"POU's are usually simple, inexpensive
technologies which positively affect the health of
rural households by reducing the prevalence of
water borne diseases".
REALITY:
POU devices do not necessarily positively affect
health simply by delivering cleaner water to
households .
Correlation between water pollution level and
occurrence of diarrhoea in household about 0.3
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Reasons for the mismatch
Contamination occurs in two different domains:
 Public
 Domestic
To realise maximum and sustainable benefit,
prevention of disease should occur in both
domains
Assessments often carried out too soon after
implementation
Hawthorne effect causes initial improvement that
does not last
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Reasons for the mismatch
Confounders present in studies announcing reduction of
diarrhoea.
Such studies did not adequate take into account:
 Home hygiene behaviour - recontamination
 Domestic sewage disposal
 Food storage and preparation practices
 Quality of irrigation water used for fresh produce
 Availability of soap and drying material for handwashing
 Vector transmission (flies, rodents, cockroaches ...)
In addition, low water sampling frequency gave wrong
impression of water quality used in homes.
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40 - 60 persons per toilet
Standpipes also disposal points for dirty water
No safe place to discard wash water - runs into stormwater drains
Animal and human feet bring contamination into homes
Poor solid waste removal causes contamination
Drains running over due to stormwater intrusion
Example of "backyard shacks"
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Problems in low-cost housing settlements:
•
58% of RDP type houses in our study had non-operational
toilets at time of visit
•
100% of houses had visible serious structural damage (leaking
roofs, leaking walls, broken taps...)
•
40% of RDP houses had one or more persons who had
diarrhoea in the previous two weeks
•
61% of households dispose of dirty water and wet waste by
flushing it down the toilet
•
100% of inhabitants said they did not know how to maintain
their houses
•
Only two households paid for water
The “kitchen” in many low cost houses
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Improved kitchen in RDP house
Tap in toilet with no connection to drain
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No place to discard washing water - runs into storm water drains
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Evidence of alcohol misuse
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The HIV/AIDS complication
The large number persons living with of HIV/AIDS
increases the already considerable number of persons
who are particularly susceptible to waterborne
diseases
What is often forgotten is that HIV/AIDS sufferers also
secrete millions of pathogens into their environment they act as 'incubators'
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POU devices have low uptake
POU devices are reported to have low uptake in
communities needing clean water the most.
This occurs even where they are distributed for free.
Filter devices are more popular than chemical
treatment because of complaints of off-taste.
Effective implementation ("marketing") will have to go
beyond standard messages about water and health.
Active and sustainable teaching of home hygiene will
go a long way towards realising the benefits of POUs
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We understand it,
but we do not respect it.
Acknowledgements
 The hosts of the meeting for the opportunity to speak
 Flemish Government, Water Research Commission, Harry
Crossley Foundation, German Academic Exchange (DAAD),
National Research Foundation and Stellenbosch University for
research assistance
 Stellenbosch University for ethical clearance
 Stellenbosch University Water Institute
Thank you for your interest
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