San Michele di Ganzaria phytodepuration plant
4 June, 2050
Waste water source
Municipal wastewater is collected from the houses of San Michele di Ganzaria (11,000 population equivalent). From 2001, the treated effluent from the conventional wastewater treatment plant of San Michele di Ganzaria was further followed with a tertiary treatment including two horizontal subsurface flow (H-SSF) constructed wetlands (CWs). The phytodepuration process’ water quality is monitored by chemical (nitrogen, phosphorus, BOD5, COD, SST) and microbiological parameters (E. coli, Salmonella, fecal Coliforms, Enterococcus faecalis).
The treated water is pumped to a nearby uphill reservoir, and from there distributed through underground pipes.
Various types of experiments took place with the reclaimed water from San Michele di Ganzaria.
From March 2001, the reclaimed water effluent was applied to 150 ha of nearby located olive orchards. Irrigation is performed with surface irrigation.
From 2004 to 2009 an experiment was conducted on tomato crops with 4 different types of drip irrigation systems.
From 2008 to 2009 an experiment was conducted irrigating eggplants (by surface drip irrigation) and tomato plants (by surface drip irrigation).
Waste water treatment description
Nutrient removal : Phytodepuration: four horizontal subsurface flow (H-SSF) constructed wetlands treat the secondary effluent of municipal wastewater. The vegetation of the constructed wetlands was Phragmites sp. A decrease in both physicochemical and microbiological parameters was observed
Pesticide removal : none
Disinfection : Phytodepuration (see above)
Suspended solids removal : none
The phytodepuration beds have a capacity of about 800 m³/day. The used storage basins have a total volume of 25,300 m³. The facility works all year round and all the treated water is used only for irrigation purposes.
Extent of the agricultural beneficiaries
The irrigated area covers about 80 ha, serving 10 local farms.
The operational cost is about 2,000,000 euros and the maintenance cost is being defined.
Type of agreement
Currently local farmers have organized themselves by establishing a consortium. The agreement between the municipality and the farmers' consortium in currently under development.
A five-year monitoring study (from 2001 to 2005) (Cirelli et al., 2007) of the horizontal subsurface flow (H-SSF) constructed wetlands (CWs) showed a good performance of the tertiary treatment. Parameters of TSS, BOD, COD, Total N and Total P of the effluent met the Italian standards for agricultural irrigation use. Although the constructed wetland could achieve a sufficient removal of Salmonella, barely 15% of the sample matched the E.Coli limits for irrigation reuse.
Another experiment (Cirelli et al., 2012) applying the reclaimed water in 2008 and 2009 to vegetable crops showed good results for tomato crops (22% higher yields) irrigated with subsurface drip emitters. The eggplants showed water stress due to clogging of the surface drippers (due to high levels of calcium carbonate and pH).
The six-year long trial (Aiello et al., 2013) assessing the risk related to reclaimed water irrigation of tomato crops concluded the following: “The TWW distribution along the irrigation seasons significantly affected soil hygienic features especially in the soil top layer. However, a soil quality recovery was observed during the winter periods. No significant contamination was found on tomato fruits not in contact with soil and plastic mulching, whereas a not negligible E. coli content was recorded under the worst-case condition of fruit growth in contact with the irrigated soil.”
Scientific results references
Cirelli, G. L., Consoli, S., Di Grande, V., Milani, M., & Toscano, A. (2007). Subsurface constructed wetlands for wastewater treatment and reuse in agriculture: Five years of experiences in Sicily, Italy. Water Science and Technology, 56(3), 183–191. https://doi.org/10.2166/wst.2007.498
Cirelli, G. L., Consoli, S., Licciardello, F., Aiello, R., Giuffrida, F., & Leonardi, C. (2012). Treated municipal wastewater reuse in vegetable production. Agricultural Water Management, 104, 163–170. https://doi.org/10.1016/j.agwat.2011.12.011
Ventura, D., Barbagallo, S., Consoli, S., Ferrante, M., Milani, M., Licciardello, F., & Cirelli, G. L. (2019). On the performance of a pilot hybrid constructed wetland for stormwater recovery in Mediterranean climate. Water Science and Technology, 79(6), 1051–1059. doi: 10.2166/wst.2019.103
Ventura, D., Consoli, S., Barbagallo, S., Marzo, A., Vanella, D., Licciardello, F., & Cirelli, G. (2019). How to Overcome Barriers for Wastewater Agricultural Reuse in Sicily (Italy)? Water, 11(2), 335. doi: 10.3390/w11020335
Russo, N., Marzo, A., Randazzo, C., Caggia, C., Toscano, A., & Cirelli, G. L. (2019). Constructed wetlands combined with disinfection systems for removal of urban wastewater contaminants. Science of The Total Environment, 656, 558–566. doi: 10.1016/j.scitotenv.2018.11.417
Licciardello, F., Milani, M., Consoli, S., Pappalardo, N., Barbagallo, S., & Cirelli, G. (2018). Wastewater tertiary treatment options to match reuse standards in agriculture. Agricultural Water Management, 210, 232–242. doi: 10.1016/j.agwat.2018.08.001
Ramírez-Cuesta, J., Vanella, D., Consoli, S., Motisi, A., & Minacapilli, M. (2018). A satellite stand-alone procedure for deriving net radiation by using SEVIRI and MODIS products. International Journal of Applied Earth Observation and Geoinformation, 73, 786–799. doi: 10.1016/j.jag.2018.08.018
Castorina, A., Consoli, S., Barbagallo, S., Branca, F., Farag, A., Licciardello, F., & Cirelli, G. (2015). Assessing environmental impacts of constructed wetland effluents for vegetable crop irrigation. International Journal of Phytoremediation, 18(6), 626–633. doi: 10.1080/15226514.2015.1086298
Aiello, R., Cirelli, G. L., Consoli, S., Licciardello, F., & Toscano, A. (2013). Risk assessment of treated municipal wastewater reuse in Sicily. Water Science and Technology, 67(1), 89–98. doi: 10.2166/wst.2012.535
Toscano, A., Hellio, C., Marzo, A., Milani, M., Lebret, K., Cirelli, G. L., & Langergraber, G. (2013). Removal efficiency of a constructed wetland combined with ultrasound and UV devices for wastewater reuse in agriculture. Environmental Technology, 34(15), 2327–2336. doi: 10.1080/09593330.2013.767284
M, Politeo & Borin, Maurizio & Milani, Mirco & Toscano, Attilio & Molari, G. (2011). Production and energy value of phragmites australis obtainedfrom two constructed wetlands. 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany
Toscano, A., Langergraber, G., Consoli, S., & Cirelli, G. L. (2009). Modelling pollutant removal in a pilot-scale two-stage subsurface flow constructed wetlands. Ecological Engineering, 35(2), 281–289. doi: 10.1016/j.ecoleng.2008.07.011
Aiello, R., Cirelli, G. L., & Consoli, S. (2007). Effects of reclaimed wastewater irrigation on soil and tomato fruits: A case study in Sicily (Italy). Agricultural Water Management, 93(1-2), 65–72. doi: 10.1016/j.agwat.2007.06.008
Barbagallo, S. , Cirelli, G. L., Consoli, S., Faro, G., Giammarco, G., Indelicato, S., Pignato, S., Toscano, A. (2003) LA FITODEPURAZIONE DI ACQUE REFLUE URBANE PER IL RIUSO A SCOPO IRRIGUO: UN CASO STUDIO SICILIANO. Ingegneria Ambientale XXXII 34-40