Influence of multiple uses of water on the sustainability of communally-managed rural water supply systems in Zimbabwe

The utilisation of drinking water supply systems for productive uses is not a new practice in Zimbabwe and the world over. This study sought to explore how multiple uses of water, in this case community gardening as a productive use combined with domestic uses influence sustainability of communally-managed rural water supply systems. Using the independent samples t-test, it was noted that community gardening positively influences sustainability. The test was done on institutional, technical, social and financial factors of sustainability. Results showed that there were statistically significant differences in sustainability performance between water points used for multiple uses and those used for domestic uses only. However, it was also noted that using drinking water sources for multiple uses increases the frequency of water use conflicts and water point breakdowns, which negatively impact on sustainability. This means that where water sources are used for multiple uses additional management skills and resources may be required for the water points to be sustained. The study concluded that using domestic water sources for productive purposes enhances sustainability of water supply facilities; however, consideration has to be given about the relative importance and scale of the type of productive activity to be implemented.

). These studies reveal how various socio-economic factors affect sustainability in many rural contexts. It is in this context that this paper seeks to explore how multiple uses of water, in this case community gardening, as a productive water use combined with domestic uses influence sustainability of water supply systems. The main question that the paper seeks to ask and answer is: 'whether there are differences in sustainability performance between water points that are used for multiple uses (watering community gardens and domestic uses) and those used for domestic uses only'.
A water system is considered to be sustainable if it is maintained in a condition that ensures reliable and adequate water supply that is beneficial to all users.

METHODOLOGY Study area and sampling procedures
The study was carried out in three provinces of Zimbabwe which are Manicaland, Matebeleland South and Masvingo.
In each of these provinces, one district with the highest number of NGOs implementing water projects at the time of the study was purposively selected. As a result, Chivi District in Masvingo Province, Nyanga District in Manicaland Province and Gwanda District in Matabeleland Province were selected. The location of the study districts in Zimbabwe is shown in Figure 1.
Water availability varies across the study districts.
Gwanda and Chivi districts are characterised by low and frequently variable rainfall that ranges between 450 and 600 mm per year. The districts have experienced meteorological and hydrological droughts in the past decade. The main sources of domestic water in the two districts are boreholes fitted with bush pumps, wells fitted with windlass and sand abstraction sites fitted with rower pumps. On the other hand, Nyanga District is situated in a cool and wet region that generally receives more than 1,000 mm annual rainfall.
The main water sources include springs, boreholes, and both shallow and deep wells. In the three districts, water from protected sources is generally of good quality, although some boreholes produce hard water.
In each district four wards were randomly selected for the study. Stratified random sampling was used to select water points used for multiple uses and specifically for domestic purposes only. Notably, all of the 40 water points used for community gardening across the study wards were selected because the number was relatively small and manageable. The targeted number of water points used for domestic purposes only was the same as that of the targeted water points for multiple uses per district. Hence, a total of 80 water points was targeted. In Nyanga district 40 water points were studied while 12 were studied in Chivi and only 8 were studied in Gwanda. Other productive uses of water, such as brick moulding and livestock rearing, were in each ward while eight interview sessions were conducted at district level in each district.

Document analysis
The types of documents reviewed in this study include meeting agendas, meeting attendance registers, and minutes of meetings which were obtained from Water Point Committees (WPCs). Various documents of water points used for community gardening provided background information on how multiple uses of water have positively or negatively affected sustainability. This allowed comparisons of sustainability to be made between pre-garden and during-garden in the study area.

Quantitative analysis
Statistical Package for Social Sciences (SPSS) version 23 was used to analyse quantitative data.  Table 1. These factors and sub-factors were derived from the literature on rural water supply and they were found to be the most recurring ones.
During performance scoring, several questions were asked to WPCs and water users to assess the field performance of each sub-factor. Data were assigned scores using the methodology developed by Kaliba (). The methodology is based upon the principle that a value of 1 represents a positive contribution towards a sub-factor and 0 represents no contribution. The methodology was adopted since it is suitable for the assessment of the sustainability of rural water supply systems (Peter & Nkambule ).
The weight of each factor which was assigned through the AHP was then multiplied by the factor's performance score obtained in the field to get the sustainability score for that factor. The summation of the sustainability scores for all the factors then gave the overall sustainability score of an individual water point so that it was classified as highly sustainable, sustainable, partially sustainable or not sustainable, as shown in Table 2.
All the water points were then classified according to their sustainability scores.

Independent samples t-test:
The independent samples ttest was used to answer how multiple uses of water influence sustainability. The 5% level of significance was used to determine if two sample means were significantly different. The hypotheses which were tested using this test were on average performance scores of sustainability factors which are social, technical, financial and institutional. Below is an example of the hypotheses: H 0 : There is no difference in the average financial scores of water points used for multiple uses and those used for domestic purposes only.
H 1 : There is a difference in the average financial scores of water points used for multiple uses and those used for domestic purposes only.

Qualitative analysis
The thematic approach was used in the analysis of qualitative data. After coding, data were then grouped into themes.
For example, all information related to financial factors of sustainability such as presence of an O&M fund, regularity of making financial contributions and rules on fee collection formed one theme. This was done for all the other factors of sustainability.

Socio-economic status of households
The study had a total of 80 water points and a total of 300 households participating in the study across the three districts. The number of interviewed women was 211 while only 89 men were interviewed. This is largely a reflection of the prevalence of female-centred households in the rural areas of Zimbabwe. The socio-economic status of the households is shown in Table 3.
The family sizes across the districts ranged between 1 and 14 people. The chi square test results (χ 2 ¼ 4.210, df ¼ 2, show that there is no significant difference in the family sizes across the three districts. However, the level of education attained by the respondents across the show that there is no significant difference in the level of education of the respondents across the districts. The majority (90%) of the respondents considered themselves to be unemployed. The striking minority who considered themselves employed reported to be formally employed (2%), self-employed (3%) and informally employed (5%). Due to the high level of unemployment, the households in the study districts had low levels of income which were below the national poverty datum line of US$481 for a household of five (ZimStat ).
The main source of income in the three districts was crop production. Although the respondents showed that they had several sources of income, the sources contributed very little towards the total household income, leaving the households susceptible to poverty. Across the three districts, women were the main participants (72%) in community gardening.

Sustainability classification for water points
Sustainability scores were calculated by multiplying the subfactor weights by the performance scores as explained in the Methodology section. The results show a major difference in the sustainability of water points used for multiple uses and those used for domestic uses only, as shown in Figure 2. Figure 2 shows that 79% of the water points used for domestic purposes only were in the 'not sustainable' and 'partially sustainable' categories, while water points used for multiple uses had 21% in the same categories. The inde- that there is a significant difference in the sustainability scores between water points used for multiple uses and those used for domestic purposes only.
Influence of multiple uses of water on sustainability of water supply systems The results of the independent sample t-test showed differences in sustainability performance between water points used for multiple uses and those used for domestic purposes only in financial, social, technical and institutional factors as presented in Table 4. Variations were also shown in sub-factors tested under each factor.
Influence of multiple uses of water on financial factors Table 4 shows that there was a significant difference in the financial performance of water points used for multiple uses and those used for domestic purposes only, thereby rejecting the null hypothesis that there is no difference in the average financial scores between water points used for multiple uses and those used for domestic purposes only.

Influence of multiple uses of water on social factors
There was a significant difference in the social factor scores of water points used for multiple uses and those used for domestic purposes only (t ¼ 3.451, p ¼ 0.000). The null hypothesis that there is no difference in the average social factor scores between water points in the two groups was water management meetings at water points used for multiple uses than those that are used for domestic purposes only.

Influence of multiple uses of water on technical factors
The independent samples t-test results (t ¼ 4.602, p ¼ 0.000) show a significant difference in the average technical scores between the two groups, resulting in the rejection of the null hypothesis that there is no difference in the average technical scores of water points between the two groups.
Maintenance frequency is one of the technical variables which was analysed and the independent samples t-test showed a significant difference in maintenance frequency between water points used for multiple uses and those used for domestic purposes only (t ¼ 3.482, p ¼ 0.001). The variables which were included under the technical factor were frequency of breakdowns per year and the maintenance frequency per year. The frequency of maintaining water points was high at water points used for multiple uses due to the presence of maintenance committees.
Water points used for multiple uses had more breakdowns per year than those used for domestic purposes only. The independent samples t-test shows a significant difference in the breakdown frequency of water points in the two groups (t ¼ 6.328, p ¼ 000). Key informant interview results from 54% of the respondents showed that breakdowns were high at water points used for multiple uses during the dry season when the demand for water by garden farmers is high. However, although frequencies of breakdowns were found to be high at water points used for multiple uses, the downtime period was low as garden farmers attended to the breakdowns quickly.

DISCUSSION
This paper sought to explore how the use of drinking water sources to irrigate community gardens as a productive use influences sustainability of water supply systems. There was a distinct sustainability performance of water points used for multiple uses and those used for domestic purposes only. The results showed a statistically significant difference on the sustainability performance of water points across the studied districts.
The independent samples t-test showed that water points used for multiple uses were performing better than those used for domestic purposes only in all the financial variables with a statistically significant difference. However, these results differ from those by Smits et al. (b)   The inclusion of women in community gardening has the potential to economically capacitate them as the majority were unemployed. Women were found to have two-fold interests in the water points, hence their commitment to make financial contributions. Despite the productive uses, the same water points were also used for domestic purposes.
With the results showing that women are the primary water collectors for domestic uses at household level, maintaining the water points through financial contributions is of great benefit to them. It is therefore imperative that although men may participate in community gardening activities, the gender dynamics surrounding the commitment in water point management and maintenance where multiple uses of water is practised have to be considered.

CONCLUSION
This paper has shown that using drinking water sources for multiple uses such as community gardening positively influences sustainability of water points. Based on the ttests results of institutional, technical, social and financial factors, there was a significant difference in sustainability performance of water points used for community gardening and those used for domestic purposes only. Generally, water points used for community gardening had functional water user committees and O&M funds as compared to those used for domestic purposes only. The average downtime of water points used for community gardening was lower than that of water points used for domestic purposes only, mainly due to high maintenance frequency of water points used for community gardening. However, it was discovered that using drinking water sources for multiple uses increases the frequency of water use conflicts and water point breakdowns, which negatively impact on sustainability. This means that where water sources will be used for multiple uses, additional management skills and resources may be required for the water points to be sustained.
The foregoing sections show that sustainability of rural water supply systems, which is a rural development challenge in Zimbabwe and other countries in Southern Africa, can be improved by using drinking water points for multiple uses. In light of this, policies and programmes in the water sector should promote the use of drinking water points for productive uses whose relative importance to the water users may influence better management of the water facilities. Where multiple water uses would have been promoted, water practioners should capacitate the user communities with appropriate skills, especially in conflict management for the benefits of multiple water uses to be maximised.

DISCLOSURE STATEMENT
No potential conflict of interest was reported by the authors.

DATA AVAILABILITY STATEMENT
All relevant data are included in the paper or its Supplementary Information.