Wastewater Irrigation of Food Crops
About
Research by our group has estimated that about 10% of the world’s food is grown using irrigation with untreated or inadequately treated wastewater (Thebo et al. 2017). This practice can be beneficial to farmers because wastewater is a reliable source (it flows all year round) and it contains nutrients and organic matter that are beneficial to crops and soil health, allowing higher crop productivity and the ability to grow crops during the dry season. However, the pathogens present in wastewater present a risk to farmers, their families, and handlers and consumers of the produce. Another focus of our research has been quantifying pathogen levels for risk assessments, and assessing strategies to reduce pathogens through natural treatment.
Selected Publications
Sheikh, B., K. Nelson, A. Thebo, B. Haddad, T. Gardner, J. Kelley, A. Adin, R. Tsuchihashi, S. Spurlock, N. Funamizu. (2019) “State of Irrigated Agricultural Water Reuse – Impediments and Incentives”. Final Report for Project Reuse-15-08/4775, Water Research Foundation.
Thebo, A.L., P. Drechsel, E.F. Lambin, and K.L. Nelson. (2017) “A Global, Spatially-Explicit Assessment of Irrigated Croplands Influenced by Urban Wastewater Flows.” Environmental Research Letters 12(7): 074008. doi:10.1088/1748-9326/aa75d1.
Sheikh, B., K.L. Nelson, B. Haddad, and A. Thebo. (2018) “Grey Water: Agricultural Use of Reclaimed Water in California.” Journal of Contemporary Water Research & Education. 165(1): 28–41. https://doi.org/10.1111/j.1936-704X.2018.03291.x.
Hong, P.-Y., T.R. Julian, M.-L. Pype, S.C. Jiang, K.L. Nelson, D. Graham, A. Pruden, and C.M. Manaia. (2018) “Reusing Treated Wastewater: Consideration of the Safety Aspects Associated with Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes.” Water 10(3): 244. doi.org/10.3390/w10030244.
Silverman, A.I., Akrong, M.O., Drechsel, P., and K.L. Nelson. (2014) On-farm treatment of wastewater used for vegetable irrigation: bacteria and virus removal in small ponds in Accra, Ghana. Journal of Water Reuse and Desalination. 4(4):276–86.
Silverman, A. I., Akrong, M., Amoah, P., Drechsel, P., and K.L. Nelson. (2013). “Quantification of human norovirus GII, human adenovirus, and fecal indicator organisms in wastewater used for irrigation in Accra, Ghana.” Journal of Water and Health. 11(3):473-488.
Williams, G.J., B. Sheikh, R.B. Holden, T.J. Kouretas, and K.L. Nelson (2007) “The impact of increased loading rate on granular media, rapid depth filtration of wastewater” Water Research, 41(19):4535-4545.