Assessing Willingness to Reuse Treated Wastewater for Crops Irrigation, and the Consumption of Crops Irrigated With Treated Wastewater: A Case Study of Students from University of Ghana and Ashiaman Municipality, Ghana

Abstract

All life forms including human need water resources in order to live healthy, promote sustainable development and ensure their well- being. The study assessed public willingness to accept and reuse treated wastewater as an alternative water resource to support the dwindling existing water resources for irrigation and the consumption wastewater irrigated crops. A social survey based on random sampling of 232 respondents in Ashaiman, capital of Ashaiman Municipality which has a well diverse population and 204 resident students at the University of Ghana, Legon was carried out as part of the study. Some physicochemical and microbiological analyses of the raw and treated wastewater over the study period were carried out using the American Public Health Association (APHA, 2005) standard methods. The microbiological quality of the cultivated lettuce crops which were irrigated with raw and diluted treated wastewater was also assessed using the Nordic Committee on Food Analysis (NMKL, 2005) standard methods. The study indicated that majority of the respondents, 95% and 92.6% in Ashaiman and at the University of Ghana respectively were willingness to use treated wastewater for irrigation of crops and consume farm produce using irrigated wastewater. Education was significantly associated with willingness to use treated wastewater for vegetable crop irrigation such that respondents with formal education in Ashaiman and at the University of Ghana were about four (4) times more willing than those with no formal education. Knowledge of wastewater treatment processes and effluent quality was also found to be significantly associated with willingness such that respondents with some knowledge of wastewater treatment processes and of effluent quality were 0.3 times more willing to use treated wastewater for irrigation of crops and consume produce of wastewater than those without. However, age and sex did not have any significant association with willingness to reuse treated wastewater for irrigation of crops and the consumption of wastewater irrigated crops. The physicochemical quality parameters of the treated effluent were all within WHO/FAO guideline limits. The microbial quality of the treated effluent was ≤ 19.2×103cfu/100 ml for faecal coliform (FC) levels and ≤ 55.0×102 cfu/100 ml for E.coli levels. The study found no E.coli contamination in the treated wastewater irrigated lettuce since the results were < 10 cfu/ g. There were faecal coliform bacteria levels of ≤ 210 cfu/g recorded for one of the effluent treatments which also fell within the guideline limits of the International Commission on Microbiological Specifications for Foods (ICMSF) which allows for ≤105 /100 g of FC bacteria of fresh weight for unprocessed food crops. Hence, the treated wastewater was safe to be used for vegetable irrigation since the microbial quality of the lettuce was safe for consumption. The study recommends that Government and Non-Governmental agencies and other stakeholders should collaborate to educate and sensitize the general public on the potential of wastewater as a vital resource.