Evaluation and Remediation of Water Scarcity in Rural Villages of South Africa
J.O. Odiyoa*, R Makungoa and B. Mwakab
a
University of Venda, Department of Hydrology and Water Resources, P/BagX5050,
Thohoyandou 0950
b
Department of Water Affairs and Forestry, P/BagX313, Pretoria 0001
*
Corresponding author email: john.odiyo@univen.ac.za
Abstract
A study aimed at evaluating and developing remediation strategies for water scarce rural villages of South
Africa (SA) has been done. Most rural villages in SA have no or inadequate pipe borne water supply due
to no or limited water supply infrastructure and/or scarce water resources. Most rural communities abstract
untreated river water and groundwater for domestic use regardless of the health impacts. Siloam Village,
as an example of a water scarce rural village in SA has been used as a case study. Inadequacy of water
supply has been evaluated through desktop review of the typical characteristics of rural water supply
schemes and questionnaire survey of the water supply and demand. Rainwater harvested from given roof
areas for a number of gauged rainstorms were used to determine the rainwater harvesting potential and
quality, and adequacy of rainwater to supplement or fully supply the demand. Groundwater abstraction
rates and quality were monitored, and yield rates of boreholes determined. The inadequate water supply
was found to be due to insufficient yard and communal taps, poor maintenance of water supply
infrastructure and inadequate surface water resources. The rainwater harvesting potential for Siloam
Village was found to be 0.83 liters/m2 of roof /mm of rainfall and can supply 28.67 L/c/d in a year to a
family of 6 people. To ensure water security at 50 L/c/day, rainwater can serve as a supplementary source.
Rainwater quality was found to be good for domestic use if harvested after the first rainstorms have
flushed away accumulated dusts on the roofs, except for households with zinc and iron roofs. The
community borehole in Siloam Village has a borehole yield of 0.5 L/s and recommended pumping period
of 24 hours/day with the total abstractions of 1.60-4.52 m3/day during the dry period, which are less than
the recommended abstraction rate of 43 m3/day. This in addition to the borehole yields of 0.1-1.0 L/s
within pumping periods of 10-24 hrs/day in Siloam Village means that the groundwater resources are
underutilized and can be developed and operated to adequately supplement the inadequate municipal
surface water supply. Fluorides in groundwater exceeded the recommended limit of 1.5 mg/L for domestic
use. Thus, rainwater and groundwater can supplement or fully supply the water demand, provided
groundwater is treated before use, rainwater harvesting is done after first rainstorms and from roof
materials with no impact on water quality, and storage tanks are provided for rainwater storage. This
shows that water scarcity in most rural communities can be remedied by developing all their water sources
and operating them efficiently.
Key words: evaluation, remediation, rural villages, water scarcity
1. Introduction
Rural areas of South Africa are typically supplied with water from dam (reservoir) water supply
schemes or no dam water supply schemes. In rural water supply schemes where there are
reservoirs (for example Soekodibeng Village in the Sand River Catchment) or abstractions from a
weir (for example Siloam Village in Nzhelele River Catchment), water is mostly reticulated to
communal stand pipes. The main problems in such systems are lack of maintenance of the water
supply infrastructure, like repairs of broken taps (Ladki et al., 2004), limited capacity of the water
treatment works and inadequate water from dams or weirs due to hydrological conditions. The
water supplied is insufficient leading to shortages. Some of the rural communities supplement
their water supply with harvested rainwater and groundwater particularly for domestic water
supply. However, mostly no quality and over abstraction for groundwater are considered. This
makes the community vulnerable to health problems and environmental degradation. The
negative impacts of groundwater over withdrawal include groundwater level deepening; spring
and river flow diminution and/or wetland surface reduction; degradation of groundwater quality,
either salinity increase or the increase of certain undesirable constituents and land surface
changes in the form of generalized or local land subsidence, or ground collapse (Stavric, 2004).
For example, groundwater abstracted from some of the aquifers in South Africa has been found to
be salty.
An example of a rural village experiencing water scarcity is Siloam Village located within the
Nzhelele River Catchment, which is one of the water stressed catchments in the Limpopo Water
Management Area. Water is mostly used for domestic purposes in the village. The homesteads
are not provided with the appropriate water supply infrastructure. The only infrastructure
provided by the government are some few communal stand pipes which are far from most
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homesteads. There are frequent shortages of water supply from the communal stand pipes. Thus,
the water supply is unreliable and inadequate. This makes the community members to use water
abstracted directly without treatment from the Nzhelele River and small seasonal rivers. Some
members of the community rely on untreated water supply from private boreholes, municipal
community borehole and springs. Preliminary survey has indicated that water from these sources
is salty and has unpalatable taste. There is also limited harvesting of rainwater for use during the
rainy season.
Studies by Mokgope and Butterworth (2001), Perez de Mendiguren and Mabelane (2001) and
Ladki et al. (2004) conducted in a number of rural villages around Bushbuckridge area in the
Sand and Sabie River Catchments revealed that the amount of water used for basic needs
(domestic) varies from 21-24.1 L/c/d while an average of 2.5-2.88 liters/m2/day is used for
irrigation. In another study by Lefebvre et al. (2005), the average water consumption was found
to be 36 L/c/d in the former homelands of Lebowa and Kwa-Ndebele located in the Olifants
River Basin. This indicates that rural communities have access to varying rates of water supply in
South Africa with some lacking access to basic water supply of 25 L/c/d.
Optimization of water supply in rural communities requires evaluation of rainwater and
groundwater as alternative sources of water supply. This is based on the fact that rainwater and
groundwater have generally been used by communities to supply their water demand or
supplement shortfalls in the water demand. In semi-arid rural areas of South Africa such as
Siloam Village, rainfall is limited (annual average of 350 mm) and thus limits the amount of
rainwater that can be harvested and groundwater yield potential. Optimization of water supply
requires reconciliation of water demand and yield from all the possible sources.
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Analyses of the available water resources and water quality are important so that environmental
impacts associated with over withdrawal and health impacts respectively, are minimized. With
regard to water quality, this is particularly so for groundwater as rainwater is generally expected
to have less water quality problems in rural areas where there are no industrial activities emitting
effluents such as sulphur dioxide that cause acid rain (Helmreich and Horn, 2008).
This study was aimed at reviewing the typical characteristics of rural water supply schemes in
South Africa; reconciling the water supply and demand, and investigating the quantitative and
qualitative characteristics of alternative sources to municipal water supply. This was aimed at
finally developing a strategy that can supplement or fully supply the demand, in order to
minimize health risks and environmental degradation, for example linked to groundwater over
abstractions.
2. Study area
Siloam Village, which is an example of a water scarce rural village in SA has been used as a case
study. Siloam Village falls under quaternary catchment A80A of the Nzhelele River Catchment
which is located in the northern region of Limpopo Province. The study area is found between
22°53'15.8'' S and 22°54'5'' S latitudes and 30°11'10.2'' E and 30°11'23.5'' E longitudes. Figure 1
shows the location of Siloam village and its water abstraction points.
3. Methods
Inadequacy of water supply has been evaluated through desktop review of the typical
characteristics of rural water supply schemes and questionnaire survey of water supply and
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demand. The questionnaire results were analyzed using the Statistical Package for Social
Sciences (SPSS) and Excel Spreadsheet. A total of 115 households were interviewed which
represented 33% of the 348 households in Siloam Village. The selection of the sample
households was based on simple random sampling method. The detailed procedure followed in
the questionnaire survey is found in Makungo (2008). Rainwater harvested from given roof areas
for a number of rainstorms and the measured rainfall depth for each storm were used to determine
the rainwater harvesting potential. The potential of rainwater in storage reservoirs to supply the
demand was analyzed from rainwater harvesting potential and long term monthly total rainfall
averages for 68 years using an average harvesting roof area of 100 m2. The detailed procedure
followed to determine the rainwater harvesting potential and analysis of harvested rainwater
stored in reservoirs to supply the demand partially or in full is found in Mashau (2006).
Rainwater samples were collected for quality analysis from 9 randomly selected houses with
different roof types between December 2006 and April 2007.
Groundwater abstraction rates were monitored from the community borehole on daily basis
during the dry period (May-September 2008). The yield rates of boreholes in the area were
obtained to determine the yield potential and compared with the abstraction rates to determine the
adequacy of groundwater resources to partially or fully supply the demand. Groundwater was
sampled from one community borehole, one private borehole and an artesian spring found in the
area of study from January to May 2007.
The physical and chemical water quality parameters recommended by DWAF (1996) and DWAF
(1998) for analyses in water to determine its suitability for domestic water supply were analyzed
in sampled rainwater and groundwater. The water quality parameters analyzed in groundwater
were also based on preliminary results by Mundalamo (2003) and Shibambo (2005) that showed
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high concentrations of fluorides and nitrates. The pH and electrical conductivity (EC) were
measured in the field using a portable multimeter. The metals and non metals were analyzed with
Inductively Coupled Plasma (ICP) and Ion Chromatography (IC) respectively. All the parameters
were analyzed in triplicates and averaged. Each parameter was then compared with the
recommended DWAF (1996) standard for drinking water quality to determine the quality status
of the water.
4. Results and discussion
4.1 Water scarcity
Typical characteristics of rural water supply schemes in South Africa obtained from desktop
literature review have been presented in Table 1. Literature review revealed that 4 of the 19
Water Management Areas (WMAs) have schemes with detailed or partially documented
information that can be used to describe the typical characteristics of rural water supply schemes
in South Africa. These WMAs include Olifants, Mzimvubu to Keiskamma, Nkomati and
Limpopo (Table 1). As an example, in Mzimvubu to Keiskamma WMA, the water supplied to the
domestic users from the different schemes is below the basic water requirement (25 L/c/d) by the
Department of Water and Environmental Affairs (DWEA) and ranges from 12 L/c/d to 24 L/c/d
(Table 1). In most of the WMAs the water requirements and the water supplied for domestic and
agricultural uses are not known. Table 1 shows that the main problems faced by rural water
supply schemes in South Africa include poorly developed infrastructure, inadequate water
sources, water wastages (due to non-payment of water services), limited treatment plant capacity
and poor maintenance and operation of the scheme. These largely contribute to water scarcity.
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The results of questionnaire survey in Siloam Village show that yard and communal stand pipes
often run dry. Due to the insufficiency of pipe borne water supply in Siloam Village to meet the
demand, residents use several water sources, including river water, groundwater and rainwater.
The water abstracted directly from the river, the springs and the boreholes is not treated before
use. This poses potential health risks as illustrated in studies by Bessong et al. (in press) and
Mashai (2007). The water use and municipal water supply survey in Siloam Village have been
estimated to be 24.9 L/c/d and 22.1 L/c/d respectively (Makungo, 2008). This confirms that the
community is currently not supplied with sufficient pipe borne water since the demand which
approximates the basic water supply of 25 L/c/d, is higher than the current municipal water
supply rate. This is despite the fact that the demand estimates were based on water people walk to
collect from different sources. This limits their consumption pattern, for example there is no
running water in houses for flushing toilets. The Limpopo Water Services (2008) recommended
the water supply rate of 35 L/c/d for Siloam village which further underscores the current
inadequacy.
4.2 Remediation
The rainwater and groundwater potential to supply part or full demand in Siloam Village and
their quality have been evaluated to provide an indication of their adequacy to act as alternative
sources that can remediate the water scarcity in Siloam Village. Improvement in water supply of
acceptable quality ensures minimum health risks.
The results of rainwater harvesting potential analysis in Siloam Village show that the average
overall volume of water harvested from galvanized iron and tiled roofs from all rainfall depths
measured per unit area of the roof per unit rainfall depth is 0.83 L/m²/mm (Table 2). This means
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that from 1 mm of gauged rainfall depth, 0.83 liters of water can be harvested from an area of 1
m². This compares well with what has been achieved elsewhere. The volume of water collected
per m² of the roof per unit depth of rainfall measured ranges from 0.8 litres to 1 liter (Hofkes,
1986). The results show that the volume of rainwater harvested per unit area of the roof per unit
gauged rainfall depth is independent of the rainfall intensity and roof type (Table 2). Thus, once,
the regional rainwater harvesting potential volume per unit area of the roof per unit rainfall depth
has been determined, the potential volume of the water harvested in each roof area and rainfall
depth can be predicted. This requires that the total roof area of the house and the total gauged
rainfall depth be known.
The volume of water that can be harvested over a roof area of 100 m2 was determined as shown
in Table 3. Rainwater harvesting takes place on part of the roof of each house, which the survey
revealed is approximately 100 m2. The monthly rainfall depths given in Table 3 and used for
computing the monthly harvestable rainwater volume were obtained by averaging the monthly
rainfall depths for 68 years. From Table 3, the potential yearly, average monthly and daily
harvestable rainwater volumes are 62772.9 L/year, 5231.1 L/month, and 172 L/day respectively.
Figure 2 gives the comparison of water harvested and the demand for water on monthly basis.
From Fig. 2, line A indicates the average monthly harvestable water, line B indicates the monthly
water demand whereas line C indicates monthly water use security recommended by Lanka
(2000) of 9125 liters for a household of 6 people with per capita demand of 50 L/d. Harvestable
water per month exceeds the demand by an excess amount of 668.6 litres. The average monthly
water demand is 4562.5 Liters/month for a household of 6 people with per capita water demand
of 25 L/d. This simply implies that rainwater harvesting can meet the demand based on the basic
standard of supply of 25 L/c/d set by the DWEA. However, it cannot assure water security of 50
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L/c/d based on Lanka (2000).
Figure 3 has been plotted following a hydrological year (beginning of the rainfall season)
corresponding to the month in which the tank is most likely to be empty. The monthly
harvestable volume of water fills the storage tank gradually during the rainy season. If the
harvesting tank is of adequate size, the owners of the roof could distribute the harvested water for
use in a whole year, with daily withdrawal of 172 litres per household of which they can share
28.67 L/c/d for a household with an average number of six people.
Point Y (Fig. 3), where the line ends, is the point where the tank is expected to be emptied if
water is abstracted on daily basis, though it should be filled again almost immediately with the
onset of the new rainy season. However, if no abstraction of water occurs, it is the point where
the tank is expected to be full. Point Z (Fig. 3), the arrow pointing from the water supply line to
the end of the bar, indicates the maximum storage capacity of the tank for storing harvested water
and should be 23.11 m³, if 5231.1 litres of water is to be supplied per household per month. The
details of how the maximum design capacity of 23.11 m³ was computed can be found in Mashau
(2006). XY (Fig. 3) indicates a steady rate of use. Since it is unlikely that any household would
draw exactly the same volume from the tank on every day of the year, it is more realistic to think
about people using their tanks according to rapid depletion method or in terms of the water
demand. Thus, supplying the water in terms of the water demand to ensure water security of 50
L/c/d would lead to each household using 9125 litres per month as recommended by Lanka
(2000).
The rainwater harvested will not be expected to be available for utilization the whole year if rapid
depletion method is applied. In Table 4, the rapid depletion method is applied at the rate of
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drawdown of 50 L/c/day. This results in harvestable rainwater of 830.1 litres being stored only in
the month of February (Table 4). All the water harvested in the other months of the year is used
without storage. A paradoxical choice which often has to be made between large tank capable of
meeting a rationed rate of consumption over a whole year and a small tank capable of providing
for greater consumption on rapid depletion basis. For most households the latter will be realistic
if it is supplemented by other sources of water. Thus in Siloam Village rainwater harvesting can
provide 28.67 L/c/day for the whole year. However, to ensure water security and meet multiple
demands, rainwater harvesting must be treated as a supplementary source to other alternative
sources of water supply.
Rainwater had EC and pH values that were within the DWAF (1996) standards for domestic use
(Table 5) indicating that the physical quality of rainwater was generally acceptable. However, H6
had a pH value of 5.73 measured in the month of March, which makes water to be slightly sour
but has no health effects (DWAF, 1998). The results of the rainwater chemical quality analyses
are given in Tables 6 and 7. The mean concentrations of all the chemical water quality parameters
analyzed fell within the recommended DWAF (1996) standards for domestic water use (Tables 6
and 7). However, metals such as zinc in houses 3, 4, 8 and 9 in some months and iron in house
number 8 in April and non-metals such as fluoride in house number 8 and phosphates in about
half of the houses in the months of December and January were slightly above the DWAF (1996)
standards for domestic water use. High levels of fluorides and phosphates in the months of
December and January may have been due to the fact that the collected samples were from the
first flush rains for the 2006/2007 rainfall seasons which were likely to pick up the pollutants
from the dust on the roofs. Though the rainfall season starts from October, the 2006/2007 rains
delayed and started in December in the Nzhelele Catchment which is situated on the leeward side
of the Soutpansberg Mountains. It was important to analyze the quality of rain water at the
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beginning of the rainy season in order to establish the month in which it is safe to harvest
rainwater of acceptable quality. Thus, in Siloam Village rainwater should be harvested after the
first flush rains.
Significant levels of zinc and iron were found in houses with roof types made from materials
which contain zinc and iron. Water with zinc concentrations ranging from 3-10 mg/L, which the
values measured did not exceed, has a bitter taste and no health effects on human life (DWAF,
1996). Iron concentrations ranging from 0.1-0.3 mg/L, which only two of the measured values
reached, has very slight effects on taste and marginal aesthetic effects (deposits in plumbing and
associated problems may begin to occur) but the water is generally well tolerable (DWAF, 1996).
Thus, though some of the zinc and iron concentrations were higher than the DWAF (1996)
recommended standards for domestic use, they have no health impacts on human beings.
However, to eliminate any potential health problems, rainwater harvesting should either not be
done in households with such roof types or the water should be treated for zinc and iron before
domestic use.
Table 8 gives the daily groundwater abstractions for the dry period (May-September 2008) from
community borehole number H27-0138 located in Siloam Village. The total daily abstractions
ranged from 1.6 m3 to 4.52 m3 (Table 8) and were far much less than the maximum recommended
daily abstraction from the GRIP database of 43 m3/day. The mean daily abstraction from the
borehole was 2.60 m3/day. Information from the GRIP database on which the daily abstractions
rate is based show that this borehole has a yield of 0.5 L/s and recommended pumping period of
24 hours/day. Information from the GRIP database also shows that boreholes within Siloam
Village generally have borehole yields ranging from 0.1-1 L/s and recommended pumping
periods ranging from 10-24 hours. This shows that the groundwater resources are available in
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relatively good quantities in the study area and are currently underutilized. The potential for
groundwater development to supplement the inadequate municipal supply therefore exists.
Table 9 gives the physical quality of groundwater sampled from the community borehole number
H27-0138 (GW1), an artesian spring (GW2) and private borehole (GW3). Groundwater in Siloam
Village generally has acceptable pH values though the pH of GW1 slightly exceeded the
maximum allowable DWAF (1996) standard for domestic use by 0.03-0.11 (Table 9). DWAF
(1998) has indicated that pH values in the range 9-9.5 have no significant impact on human health
though it slightly impacts on the taste of water. Thus, pH of GW1 had no significant impacts on
human health. The EC values were, however, within the DWAF (1996) recommended standard
for domestic use.
The groundwater chemical quality for GW1 and GW2 were generally within the DWAF (1996)
standards for domestic use except for fluorides which were higher than the recommended
standard of 1 mg/L (Table 10). Calcium, magnesium and nitrates concentrations in GW3 were
mostly higher than the recommended standards of 32, 30 and 6 mg/L respectively. However, the
fluorides concentrations of GW3 though higher than the recommended standard, were lower than
those in GW1 and GW2. Pauwels and Ahmed (2007) indicated that the decrease in concentration
of calcium in water results in an increase of fluorides concentrations in water. Thus, water in
GW3 with high concentrations of calcium, resulted in the reduction of the concentrations of
fluorides. The high concentration of fluoride in groundwater in the study area can be attributed to
the geology of the area. Fluoride concentrations greater than 1.5 mg/L cause fluorosis (molten
teeth). A survey by Mashai (2007) has indicated that 50% of learners in Siloam Primary School
and 85% of the households in Siloam Village have people with molten teeth due to the use of
groundwater.
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The high levels of calcium, magnesium and nitrate in GW3 can be attributed to the agricultural
practices and washing of clothes in the neighbourhood of the borehole. The leaching of fertilizers
containing nitrates and decomposition of dead plants contribute to increased concentrations of
nitrates in the groundwater aquifer. Calcium and magnesium found in soap which is used for
washing is also leached into the groundwater aquifer. The total hardness of water is the sum of
calcium and magnesium concentrations expressed as mg/L (DWAF, 1998). Hard water causes
impairment of lathering and corrosion of household appliances (DWAF, 1998). Hard water,
however, has no impact on human health at concentrations below the maximum allowable limit
of 200 mg/L of calcium carbonate (DWAF, 1998). Water with nitrates concentrations greater than
20 mg/L causes methaemoglobinaemia and mucous membrane irritation in infants and adults
respectively. Thus, the use of groundwater in GW3 had very high health risks and to a limited
extent GW1 and GW2 respectively. Phosphates, copper and cadmium were not detected in all the
sampling points throughout the monitoring period.
5. Conclusion
The study has shown through literature review that rural water supply schemes in South Africa
are typically characterized by poorly developed infrastructure, inadequate water sources, water
wastages (due to non-payment of water services), limited treatment plant capacity and poor
maintenance and operation of the scheme. These impacts on the quantity and quality of water
supplied to rural communities leading to potential health risks.
The research established that a unit volume of 0.83 litres per m² of roof per 1 mm of rainfall can
be harvested in Siloam Village. Analysis carried out with a house roof size of 100 m² in the area
established that the residents of Siloam Village can on average withdraw the harvested rainwater
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stored in the tanks at the rate of 172 L/household/day (28.67 L/c/d) for the whole year. However,
a more realistic distribution of use can be achieved through rapid depletion method. Thus,
rainwater harvesting has the potential to alleviate the problem of water supply in Siloam Village.
The results of the rainwater quality analyses show that the rainwater quality was generally good
with the exception of high levels of fluoride and phosphate at the beginning of the rainy season
indicating that the roofs needed to be first flushed before rainwater harvesting for domestic use.
The pollutants could be associated with the dust from the roofs. However, elevated levels of zinc
and iron associated with house roof types have been recommended for treatment after harvesting
of the water or the roof types should not be used for rainwater harvesting.
The community borehole located in Siloam Village has a yield of 0.5 L/s and recommended
pumping period of 24 hours/day. The study findings showed that the total daily abstractions
during the dry period ranged from 1.6 m3 to 4.52 m3 and were far much less than the maximum
recommended daily abstraction of 43 m3/day. Comparison of this and the general groundwater
yield rate in the area of 0.1-1 l/s in 10-24 hours/day indicate that significant amount of
groundwater resources can be developed further and operated efficiently to supplement the
inadequate municipal water supply. The physical water quality of groundwater in Siloam Village
is generally acceptable. Though groundwater resources are yielded in sufficient quantities in
Siloam Village, they are not fit for human consumption before treatment due to high fluorides
exceeding maximum allowable DWAF (1996) standard for domestic use of 1.5 mg/L. Fluorosis
has been found in 50% of learners and 85% of households in Siloam Village.
The nitrate levels in certain boreholes are at concentrations that cause methaemoglobinaemia and
mucous membrane irritation in infants and adults respectively. Thus rainwater and groundwater
can supplement the water demand, provided groundwater is treated before use and harvesting is
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done after the first rains have cleaned the roof and from roof materials with no impact on water
quality. The study has shown that water scarcity in rural communities in SA can be remedied by
developing all the water sources in their neighborhood and operating them efficiently.
Acknowledgements
The authors wish to acknowledge the Department of Water and Environmental Affairs (DWEA)
for supporting the project on “Bulk Water Supply Systems Operation: Evaluation and Monitoring
Support”, from which part of the data used in this study was generated. Mrs C. Ntuli and Ms. N.
Mthethwa from DWEA are also acknowledged for their valuable contributions. Ms. Makungo
T.E, Mr. Mashau F, Mr. Seakammela M.M and Mr. Mothetha M.L are also acknowledged for
conducting different aspects of questionnaire survey, rainwater harvesting and groundwater
abstractions monitoring. The Siloam Village community is also acknowledged for its
participation during the questionnaire survey and rainwater harvesting. In particular we wish to
express our sincere gratitude to the Siloam Village Chief Mr. Mugwena and civic member Mr.
Tshinamune for permission to conduct research. The former Department of Environmental
Affairs and Tourism is also acknowledged for providing start up funds through NzheleleMakhado Project to the School of Environmental Sciences of the University of Venda.
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