The impact of irrigation water management techniques on the performance of rice using treated wastewater reuse in Durban, South Africa Isiaka Toyin Busari, Aidan Senzanje, Alfred O. Odindo and Chris A. Buckley ABSTRACT The need to cultivate effluent-irrigated rice is paramount and synonymous with treated wastewater reuse, recycling and water resources management. A trial in a peri-urban set-up with a low-cost decentralized wastewater treatment system (DEWATS) was carried out in the 2017 and 2018 cropping seasons to assess the effect of irrigation water reuse management techniques on the yield and water productivity of rice. It was hypothesized that anaerobic baffled reactor (ABR) irrigation water management does not have an effect on the yield of peri-urban grown rice. The impacts of irrigation water management techniques were very significant (P < 0.001) on the number of irrigation events, amount of irrigation and daily water balance. The impact was not significant (P > 0.05) on the tiller numbers per plant; it was however significant (P < 0.05) on the panicle numbers per plant. The effects were not significant (P > 0.05) on the plant height but significant (P < 0.05) on the yield rice for both trials. The effect was also significant (P < 0.05) on water productivity. The result proved that the hypothesis be rejected. It could be concluded that significant potential exists for applying wastewater reuse for non-drinking applications such as irrigation. Isiaka Toyin Busari (corresponding author) Aidan Senzanje Bioresources Engineering, School of Engineering, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, KwaZulu-Natal 3209, South Africa E-mail: bitbabadudu1@gmail.com Alfred O. Odindo Crop Science, School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa Chris A. Buckley Pollution Research Group, Chemical Engineering, School of Engineering, University of KwaZulu-Natal, Durban 4041, South Africa Key words | anaerobic baffled reactor (ABR), DEWATS, effluent, peri-urban agriculture, reuse INTRODUCTION Several communities in the Republic of South Africa struggle to get dependable and sufficient quantities of fresh water for various water requirements, hence, interest is increasing in the reuse of wastewater for non-drinking water requirements such as irrigation (Adewumi et al. ). The push to use less water in agriculture is because of increasing demand generated by the growing population. It is imperative to improve irrigation efficiency and access alternative sources such as water reuse in order to guarantee sustainable agriculture that will feed the increasing populace (Ram et al. ). One of the low-cost hygiene technologies which has been effectively used in developing countries is the decentralized wastewater treatment system (DEWATS) that includes an anaerobic baffled reactor (ABR) (Adhanom et al. ). Irrigating crops with effluent is important for water reuse and recycling nutrients and is better than direct discharge into rivers (Musazura et al. ). Irrigation with treated sewage effluents constitutes an environmentally sound way of disposing effluents into the environment (de Carvalho et al. ). When using domestic treated efflu- ents, heavy metals are of less concern for irrigation because they are basically and effectively removed during common 1604 © IWA Publishing 2019 Water Supply | 19.6 | 2019 doi: 10.2166/ws.2019.031 Downloaded from https://iwaponline.com/ws/article-pdf/19/6/1604/578435/ws019061604.pdf by guest on 04 July 2020