Tertiary filtered municipal wastewater as alternative water source in agriculture: a field investigation in Southern Italy

Results are reported concerning a 2-year field investigation on municipal wastewater reclamation for the irrigation of two experimental crops: tomato and fennel. Throughout the investigation, approximately 500 m3 of tertiary membrane filtered wastewater without further disinfection was supplied to one of two parcels (500 m2 each) of a test field located in Southern Italy. The second parcel was comparatively irrigated with 500 m3 of conventional well water. Objectives of the investigation were (i) the evaluation of the performance of a membrane filtration pilot plant (productivity=0.7 m3 h−1) for tertiary treatment and (ii) the comparison between agronomic results (features of soil and crops) after irrigation with reclaimed wastewater versus conventional groundwater. Over long term operation, the pilot plant performance resulted very good in terms of suspended solids and bacterial removal. Referring to the agronomic results, no substantial differences were observed after 2 years, both in terms of microbiological quality of the crops and characteristics of the soil. The whole results indicate membrane filtered municipal effluent as a viable alternative water resource for irrigation.