Della Pietra, L. (2017). Sustainable water use in agriculture: the potential of wastewater [Master Thesis, Technische Universität Wien; Diplomatische Akademie Wien]. reposiTUm. https://doi.org/10.34726/hss.2017.45282
wastewater reuse; agriculture; irrigation water demand; water scarcity; sustainability
en
Abstract:
The natural water cycle is finding it harder to keep up with rising water demand due to population growth, climate change, increased urbanization and life-style changes. With rising water scarcity levels across the globe, new water sources like treated wastewater will be key for ensuring future sustainability. Since agriculture is the biggest global consumer of freshwater, its potential for alleviating water stress should be harnessed. For this reason, a quantitative analysis of secondary data was elaborated in this thesis. Firstly, the supply side was analysed to look at quantifying global treated wastewater production potential via municipal water withdrawal and access to improved sanitation. Secondly, this data was paired with the irrigation water demand of the three most popular dry cereal crops to estimate wastewater irrigation potential for 127 countries. While the biggest treated wastewater production potential was found in highly populated countries with high access to sanitation, the highest irrigation potential was found in countries with medium irrigation water demands and elevated amounts of treated wastewater production. Combining the calculated total irrigation demand and total treated wastewater production potential, this paper finds that treated wastewater irrigation could on average make up for almost 66 percent of total irrigation need of global dry cereal cultivation. Therefore, the paper concludes that if actual wastewater treatment infrastructure would be expanded to match the potential calculated in this study, the treated effluent could significantly alleviate water stress by decreasing agricultural freshwater withdrawals. This would not only increase global sanitation levels and water-use efficiency under 'Goal six' of 2015 Sustainable Development Goals but also increase food production in water stressed regions to combat hunger and food insecurity under 'Goal two'.