CHAPTER 4 RESULTS AND DISCUSSION
4.3 Results from questionnaire (quantitative and qualitative) analysis
4.3.3 Section C: Water quality
4.3.3.2 Water quality concern/ challenge
Under this section questions related to the main water quality concern/ challenge (QC4E/QC4F), water quality parameters of concern (QC5E/QC5F), rating of the water quality in the Breede River catchment since 2000 (QC6E/QC6F), parameter which showed most deterioration between 2000 and 2020 (QC7E), water quality comparison with other WMA (QC9E/QC8F), suitability of the
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water for irrigation purposes (QC10E/QC9F), impact of water quality on irrigation system maintenance (QB11F), and source(s) (natural and/or anthropogenic) which influence the water quality (QC8E/QC7F).
Although no regular water quality data monitoring is done throughout the year (see section 4.3.3.1), the majority of Farmers felt confident that they have a general idea of the quality of the water in the catchment and when asked to list their main concerns/ challenges they highlighted the following parameters as concerns (i.e. those classed as 2. Moderate or 3. Poor): TDS/EC (50%), Biological/ E. coli (73%), pH (27%), cations: Na, Ca, K (13%), anions: HCO3, SO4 (7%) (QC4E/QC4F) (Figure 4-29). Under “Other” the following was listed: Fe, Mn, heavy metals, hormones, siltation, solid waste (plastics etc,), and algae. The main concerns/ challenges differed across the three sections of the catchment with the majority (71%) of Farmers in the Middle Breede River section that considered the TDS/EC of moderate (to poor) quality and all Farmers (100%) in the Lower Breede River section considered the pH to be of moderate quality (QC5E/QC5F) (Figure 4-29). Farmers who indicated that the water quality in terms of biological contamination (E. coli) was moderate to poor were generally spread across all the Breede River sections, although only 50% of Farmers in the Lower Breede River section classified this parameter as moderate (Figure 4-30).
Figure 4-29: Distribution of Farmers’ opinion on the main water quality parameter of concern in the Breede River catchment (QC5F).
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
A. TDS/E B. pH C. Cations:
Na, Ca, K
D. Anions:
HCO3, SO4
E. Biological/
eColi
% participants
Water quality parameters
Rating of water quality per parameter (Farmers)
0 =No knowledge 1= Good 2= Moderate 3= Poor
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The Expert group were also asked to list their main concerns/ challenges and they highlighted the following parameters as concerns (i.e. those classed as 2. Moderate or 3. Poor): Biological/ E.coli (69%), TDS/EC (62%), Other (39%), cations: Na, Ca, K (8%), anions: HCO3, SO4 (8%), pH (0%) (Figure 4-31).
Figure 4-30: Distribution of Farmers’ opinion on the main water quality parameter of concern across the Breede River sections (QC5E/QC5F).
Figure 4-31: Distribution of Experts’ opinion on the main water quality parameter of concern in the Breede River catchment (QC4E).
0%
20%
40%
60%
80%
100%
A. TDS/E B. pH C. Cations:
Na, Ca, K
D. Anions:
HCO3, SO4
E. Biological/
eCol
% participants
Water quality parameters
Rating of water quality per parameter (Experts)
0 =No knowledge 1= Good 2= Moderate 3= Poor
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Under “Other” they listed the following: Fe, Mn, heavy metals, hormones, solid waste (plastics etc.) (QC4E/QC4F).These findings are supported by reports of poor water quality related to natural salinity (EC) in the Middle Breede River section as well as biological contamination across different sections of the Breede River related to the WWTW in the catchment (Murray, Biesenbach and Badenhorst Inc. 1989; Kirchner et al. 1997; DWAF, 2003; Cullis et al., 2018).
When asked to rate the water quality in the Breede River catchment since the year 2000 the majority of Farmers (60%) indicated that the water quality declined over the past 20 years (QC6E/QC6F) (Figure 4-32 and Figure 4-33). However, the majority (75%) of Farmers in the Upper Breede River section were of the opinion that there was no change in the water quality over this period (Figure 4-33). E.coli and TDS/EC were selected by most Farmers as the parameter(s) which showed the most deterioration. When asked the same question the majority of Experts (69%) indicated that the water quality did not change over the past 20 years with 15%
indicating that the water quality declined and a further 15% suggesting that it improved (Figure 4-34).The Experts group indicated that TDS/EC (62%) and E.coli (39%) were the parameter(s) which showed the most deterioration with pH (31%) and anions (31%) those that showed the least deterioration (QC7E).
Figure 4-32: Distribution of Farmers’ opinion on the changes in water quality in the Breede River catchment (QC6E/QC6F).
64%
0%
10%
20%
30%
40%
50%
60%
70%
A. Improved B. Remained the same C. Declined
% participants
Rating
Rating of water quality since 2000 (Farmers)
43%
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Figure 4-33: Distribution of Farmers’ opinion on the changes in water quality across categories per Breede River section (QC6E/QC6F).
Figure 4-34: Distribution of Experts’ opinion on the changes in water quality in the Breede River catchment (QC6E/QC6F).
The intention behind the inclusion of this detail was to determine the participant’s perception of the water quality in the catchment without providing them with water quality data. Based on the research findings the majority of participants perceived that there is a water quality concern
0% 0% 0%
29% 25% 25%
71% 75% 75%
0%
10%
20%
30%
40%
50%
60%
70%
80%
Upper Breede Middle Breede Lower Breede
% participants
Breede River sections
Water quality rating change since 2000 (Farmers)
A. Improved B. Remained the same C. Declined
0%
10%
20%
30%
40%
50%
60%
70%
80%
A. Improved B. Remained the same C. Declined
% participants
Rating
Rating of water quality since 2000 (Experts)
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related to salinity and E.coli which were confirmed by the re-evaluation of the water quality in the catchment presented earlier in section 4.2.
When asked to rate the water quality of the Breede River catchment compared to other catchments most participants selected the Berg River as a comparison with the Breede River (QC9E/QC8F). The majority of Farmers (47%) and Experts (46%) opined that the water quality of the BGWMA was less degraded compared to other catchments (Figure 4-35).
(a)
(b)
Figure 4-35: Distribution of (a) Farmers’ and (b) Experts’ opinion on the level of water quality degradation in the Breede River catchment compared to other similar catchments
(QC9E/QC8F).
13%
47%
33%
7%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
A. I do not know B. Less degraded than other areas
C. Same as other areas
D. More degraded than other areas
% participants
Rating
Water quality comparison with other catchments (Farmers)
23%
46%
15% 15%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
A. I do not know B. Less degraded than other areas
C. Same as other areas
D. More degraded than other areas
% participants
Rating
Water quality comparison with other
catchments (Experts)
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A water quality study on various South Africa catchments showed that many rivers in intensely farmed agricultural areas in the Western Cape and central interior (Vaal-Harts area) showed increased salination as a result of the impact of agriculture (Van Rensburg et al., 2011). This study showed deterioration of the Berg and Breede Rivers with respect to salinity. With the exception of the tributaries and parts of the lower Breede River, the salinity of these rivers were comparable, which supports the findings of the opinions of Farmers and Experts presented here.
The majority of Farmers (93%) agreed that the water quality meets requirements for the crops cultivated in 2000 compared to 80% agreeing that the water still meets requirements for crops in 2020 (QC9F) (Figure 4-36). Almost half (53%) of the Farmers interviewed indicated that water quality for irrigation purposes in the Breede River catchment meets requirements of the market (QC10F). When asked to elaborate on the water quality parameters of concern to the crops cultivated and the market requirements the majority of Farmers indicated a concern about the E.coli and salinity levels of water for irrigation purposes (QC9F) (Figure 4-37).
Figure 4-36: Distribution of Farmers’ opinion on the suitability of water for irrigation purposes in the Breede River catchment (QC9F).
93%
7% 0%
80%
20%
0%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
A. Mostly suitable for irrigation of all crops
B. Only suitable for some crops
C. Mostly unsuitable for irrigation of all
crops
% participants
Rating
Suitability for irrigation purposes (Farmers)
2000 2020
117
Figure 4-37: Distribution of Farmers’ opinion on irrigation water quality requirements of the market in 2000 and 2020 (QC10F).
However, they did not base this concern on data but what they voiced were purely concerns based on the perceptions that most municipal WWTW in South Africa were dysfunctional and that this would negatively impact on the international markets. These perceptions are not unfounded as highlighted in section 2.8. The poor operation and maintenance of WWTW throughout South Africa were point out as a cause for concern due to the large pollution contribution thereof on surface water resources (Mema, 2010). The concerns include human health impacts as well as high nutrient load and algae blooms. Although Experts were not as familiar with the requirements of the various crops and markets the majority (85%) opined that the water in the Breede River was suitable for irrigation of all crops (Figure 4-37) (QC10E).
Farmers were asked to indicate if in their opinion the water quality in the catchment has an impact on irrigation system maintenance (QB11F). The majority of Farmers (10 out of the 14 irrigation Farmers - 71%) indicated that in their opinion the water quality in the catchment did have an impact on irrigation system maintenance (Figure 4-38). However, Farmers could not provide details from their records related to the expenditure on irrigation system maintenance and repairs related to water quality between 2000 and 2020. Nevertheless, the majority of Farmers indicated that this expenditure made up less than 1% of total irrigation costs. They did indicate that although the maintenance cost was not high, the task of maintaining the irrigation system was more time consuming during late summer low flow periods. This is due to silt, algae etc. clogging the filters
0%
47% 53%
0% 0%
0%
53%
40%
0%
7%
0%
10%
20%
30%
40%
50%
60%
A. Better than required
B. Meets most requirements
C. Meets requirements
D. Not meeting important requirements
E. Not acceptable
% participants
Rating
Farmer's opinion on meeting market requirements
2000 2020
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installed to prevent damage to the irrigation infrastructure. The intervals between flushing the filters increase from the usual once per day to four or five times per day in the late summer.
Figure 4-38: Distribution of Farmers’ opinion on water quality impact on irrigation system maintenance (QB11F).
Farmers all indicated that although the cost of maintenance due to water quality concerns are not high, regular maintenance of the irrigation system was key in preventing costly replacement if this is not done. The algae growth is linked to nutrient (NO2-+NO3- and PO42-) levels which were shown to be high, especially during late summer periods. Cullis et al. (2018) also highlighted the high nutrient levels along the full length of the Breede River.
Farmers in the Lower Breede River section of the catchment indicated that the natural lower pH of water from mountain streams impacted on metal parts of the irrigation system. Corrosion of the irrigation system is countered by neutralising the pH in the holding dams and tanks before it is pumped through the irrigation system.