The performance of smallholder irrigation schemes is multidimensional and can be looked at from different perspectives. This study assessed the technical performance of the Mooi River irrigation scheme (MRIS) to derive a comprehensive set of best management practices (BMPs). This was done acknowledging that the farmer is now the water manager, in line with participatory irrigation management (PIM) and irrigation management transfer (IMT) concepts. Five performance indicators related to water supply and delivery and agricultural performance were assessed through the field measurement method during spring and summer of the 2010/2011 season. Farmers were interviewed through a questionnaire to gather suggestions on ways to improve the performance of their scheme. Their responses helped in the selection of the BMPs for the scheme which were then ranked using the analytic hierarchy process (AHP). The results show a scheme average conveyance efficiency of 86.4%, maximum dependability of irrigation interval between water applications of 2.57 in spring and the scheme relative irrigation supply of 1.48. Agricultural performance indicators-output per unit irrigation supply and water productivity (ET)-were found to be 0.64 and 5.37 kg m -3 , respectively. Irrigation scheduling was the most preferred BMP by the farmers, while volumetric measurement of irrigation water used by each block was the least preferred. This study concludes that water management in smallholder schemes is poor, thus affecting performance of these schemes, and that farmers are aware of the problems and possible solutions to perennial problems hindering performance in smallholder schemes. The study recommends deepening farmers' participation in policy formulation and derivation of BMPs. Copyright © 2013 John Wiley & Sons, Ltd. RÉSUMÉLa performance des systèmes d'irrigation des petites exploitations est multidimensionnelle et peut être regardée sous différents angles. Cette étude a évalué la performance technique de système d'irrigation de la rivière Mooi (MRIS) afin d'obtenir un ensemble de meilleures pratiques de gestion (BMP). Cela a été fait en reconnaissant que l'agriculteur est maintenant le gestionnaire de l'eau conforme à la gestion participative de l'irrigation (PIM) et en appliquant le concept de transfert de gestion de l'irrigation (IMT). Cinq indicateurs de performance liés à l'approvisionnement, la livraison et les performances agricoles de l'eau ont été évalués par des mesures au champ au cours du printemps et de l'été de la saison 2010/2011. Les agriculteurs ont été enquêtés sur les moyens pour améliorer la performance de leur système. Leurs réponses ont aidé à identifier les BMP qui ont été ensuite classées en utilisant la méthode de hiérarchie multicritère (AHP). Les résultats montrent une efficacité moyenne du système de transport de 86.4%, une régularité maximale des tours d'eau au printemps de 2.57 et un approvisionnement relatif du système de 1.48. Les indicateurs de performance agricoles-la production par commande et la prod...

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Some parts of the rural areas of South Africa are receiving water services below the legislative standards stipulated in the Water Services Act (1997) of South Africa. This is because small-scale water infrastructures (SWI), including standpipes, handpumps and windmills, are failing to supply adequate water in rural communities for various activities that enhance their livelihoods. This is due to technical, community, institutional, and environmental factors. Literature indicates that these factors are complex in nature. However, research on their complex interactions has been limited. Therefore, the complex interactions of the factors causing SWI failure were investigated and analysed in this study. A qualitative research approach was employed to investigate the factors that cause failure of SWI. The network approach combined with graph theory and the community structure method were used to generate a theme and domain network that allowed for a systematic analysis and interpretation of the causes of SWI failure in the study area. The major causes of failure identified include: (i) the use of a top-down approach to implement water projects in rural communities without consultation, (ii) sharing of SWI in high numbers due to the limited number of SWI available/functional, resulting in overloading and increased breakdowns, and (iii) drying up of water sources due to poor siting leading to vandalism of SWI. Overall, the causes of SWI failure are as a result of the complex interactions of different categories of factors. The theme and domain network is a powerful tool that can be used represent and analyse the complex interactions. It is therefore imperative for interventions aiming to improve rural water supply to analyse the complex interactions of the causes of SWI failure to understand the underlying problems at a level of a system, in order to propose suitable solutions.

South African agriculture accounts for 62% of the national water demand. Almost 45% of the water is wasted. Therefore, irrigation systems need to improve their water-use efficiency (WUE). However, the WUE of smallholder irrigation schemes in the country, including Agri-Parks, is not precisely known. A study was performed at four Agri-Parks (Rooiwal, Soshanguve, Tarlton, and Westonaria) in Gauteng province to assess the condition and performance of the irrigation systems, as part of a project that aimed to develop a WUE model for smallholder irrigation systems. The Agri-Parks were equipped with efficient irrigation systems in forms of drip and microjets. The assessments were performed at the system component level in February–March 2021. A Condition Assessment Model (CAM), developed by ARC-NRE/AE, was used for the condition assessment. Enumerators observed the system components visually and assigned conditions, which they uploaded into the model to generate condition indices (CIs). Water conveyance efficiency (CE) and distribution uniformity (DU) were assessed on delivery and infield systems, respectively. The CI values ranged 4–6, implying significant deterioration had occurred. The CE was 61–78%, while the DU was 60–95%. The infield system CI correlated positively with the DU, suggesting the CI could predict the DU in drip systems, which was encouraging for the proposed WUE model. However, further research covering a longer period and more Agri-Parks is recommended.

This study assessed the presence of key requirements for sustainable O&M and rehabilitation of rural small-scale water infrastructure in Makhudutamaga Municipality in South Africa. The study found a significant correlation between the requirements for sustainable O&M and rehabilitation of rural small-scale water infrastructure and continuity of service provision (p < 0.001) by the small-scale water infrastructure as well as functionality (p < 0.001) of the small-scale water infrastructure hardware. The study concludes that the presence of the key requirements varies as a function of social dynamics of communities and the presence of these requirements has an impact on the functionality and continuity of the small-scale water infrastructure hardware.

Irrigation water conveyance relies heavily on canal networks because they transport the water cheaply. However, water losses are high, which is a major concern in the face of soaring demand and dwindling new water sources. While researchers have investigated canal water losses and water loss types at irrigation scheme level, their variability and the main factors of influence at a global scale are still not clear. Thus, this study aims to elucidate the effects of canal water flow and soil characteristics on water losses globally. Data for 1388 canal reaches from 45 published articles are used. The results confirm that evaporation is so negligibly smaller than seepage and other water loss types that it can safely be ignored when analysing major water losses from canals. The study results also confirm that canal water losses decrease with soil clay content, due to decreasing permeability. The methods used for assessing water losses show significant influence on water losses; for example, the inflow–outflow method exhibits significantly higher water losses than the ponding technique. The current study results also show that canal shape, wetted perimeter and wetted area have a significant influence on water losses. It can be concluded from the study results that consideration of the physical mechanisms of water losses and different water loss types involved is important in future studies. It is recommended that future canal water loss studies, especially those focusing on losses via evaporation, also assess the effects of factors such as canal embankment height and depth of freeboard on the losses. These results are important for water scientists, engineers and practitioners.

Wide soil water content and temperature variations affect crop yields for reasons ranging from rate of seed germination, seed development, to plant growth. This study aimed at evaluating the extent to which drip irrigation can reduce soil water content and temperature variations. An experiment was carried out in a 154 m 2 glasshouse with Tottori dune sand of Japan. Two irrigation levels of 60 and 100% of evapotranspiration, and two dune sand covers of 2 and 5 cm on the drip lines were used. Soil water content and temperature variations were significantly (P < 0.001) reduced under the 5 cm dune sand cover but insignificantly reduced under the 2 cm dune sand cover. Minimum soil temperature was increased, and maximum soil temperature was decreased under the 5 cm dune sand cover. Irrigation level of 100% of evapotranspiration under 5 cm dune sand cover resulted in 20% dry matter yield increase of sorghum. Irrigation level of 60% of evapotranspiration under 5 cm dune sand cover resulted in no significant dry matter yield increase of sorghum. From this study, we conclude that the practical minimum depth of dune sand cover on the drip lines can be 5 cm.

South Africa has been identified as having a high potential for solar powered irrigation. However, there has been a lag in the development of solar powered irrigation systems (SPIS) there, mainly due to the high investment cost associated with solar technology. South Africa has frequently implemented load shedding, which has affected many farmers. The work reported in this paper sought to determine the extent of solar powered irrigation and characteristics of the system types in use. The extent of SPIS in South Africa was determined using a questionnaire, and categorised in terms of farm size, SPIS configuration (storage of energy), type of irrigation, and location of the system. These were established mainly from a literature search. The questionnaires were administered on Survey Monkey®. The sample size of the study was 138 755 potential respondents. The number that participated and completed the questionnaires included a total of 18 SPIS engineers, installers and designers and 13 SPIS users (farmers). The main problem encountered with the distribution of the survey was finding SPIS users to participate. Results from SPIS engineers, installers and designers showed that most SPIS they implemented were in the Western Cape and the Eastern Cape, at 33% of the responses for both provinces. The total area under SPIS was found to be 364 ha, while the area under irrigation is South Africa is 1 300 00 ha, indicating a high potential for SPIS development. Some details on the extent of SPIS in South Africa were determined in this paper, but more SPIS users need to be identified to determine the details of their SPIS.