This paper reports a study on the performance of a multistage constructed wetland (CW) system adopted for winery wastewater and on the analysis of its suitability for irrigation reuse. The CW system treats about 3 m³·day⁻¹ of wastewater produced by a small winery located in Sicily (insular Italy). Wastewater samples were collected at the CW inlet and outlet for physical–chemical and microbiological quality characterization. CW efficiency was evaluated on the basis of water quality improvement and of the achievement of Italian and EU irrigation reuse regulation limits. The CW system showed Chemical Oxygen Demand (COD) and Total Suspended Solids (TSS) mean removal rates of about 81% and 69%, and a maximum removal of about 99% (for both COD and TSS) occurred during grape harvest phase. The CW removal efficiencies for nutrients were 56% for TN and 38% for PO₄-P, considering their low average concentrations at CW inlet. The CW system evidenced an effluent average quality compatible with the limits imposed by the Italian regulation and EU proposal regulation on the minimum requirement for water reuse. The CW vegetated area showed regular growth and vegetative development; phytotoxicity phenomena were not detected. The results of the study suggest the important role of CW systems in the treatment of winery wastewater and for their subsequent reuse in agriculture.

This study reports an up-to-date summary of the principal barriers still limiting reclaimed water use for agriculture in Italy, and particularly in Sicily. Moreover, it provides a geographic informative system (GIS)-based procedure for evaluating the potential treated wastewater (TW) reuse in the Sicilian region as a decision support system for its management. The survey, based on possible economic, morphologic, and design solutions, evidenced a feasible integration of several wastewater treatment plants (WWTPs) with irrigation areas, allowing the water availability enhancement. Overall, the potential volume of TW by WWTPs (connected to irrigation districts) is 163 × 10⁶ m³ year⁻¹, while the water deficit is 66 × 10⁶ m³ year⁻¹. The feasibility of TW reuse in Sicily was also analysed at the light of the World Health Organization microbial risk assessment. Escherichia coli (E. coli) analyses mostly accomplished these guidelines while conflicting with the restrictive Italian standards. Despite several limiting factors (restrictive legislations, high distance and unfavourable slope between WWTPs and irrigable areas, high monitoring and distribution costs) still hamper the exploitation of reclaimed water use in Sicilian agriculture, some solutions were identified to implement this practice.

This paper presents the results of an experiment carried out in Southern Italy (Sicily) on the estimation evapotranspiration (ET) in pilot constructed wetlands planted with different species (Chrysopogon zizanioides, Myscanthus x giganteus, Arundo donax, Phragmites australis, and Cyperus papyrus). In the two monitored growing seasons, reference ET₀ was calculated with the Penman-Monteith formula, while actual ET and crop coefficients were measured through a water balance and the FAO 56 approach, respectively. The highest average seasonal ET value was observed in Phragmites australis (17.31 mm d⁻¹) followed by Arundo donax (11.23 mm day⁻¹) Chrysopogon zizanioides (8.56 mm day⁻¹), Cyperus papyrus (7.86 mm day⁻¹), and Myscanthus x giganteus (7.35 mm day⁻¹). For all plants, crop coefficient values showed different patterns in relation to growth stages and were strongly correlated with phenological parameters. Myscanthus x giganteus and Arundo donax showed a water use efficiency values significantly higher than those observed for the other tested species. Results of this study may contribute to select appropriate plant species for constructed wetlands located in semi-arid regions, especially when the use of reclaimed water and/or the use of aboveground biomass are planned.

This work focuses on the performance evaluation of two full-scale horizontal suburface flow constructed wetlands (H-SSF CWs) working in parallel, which have an almost equal surface area (about 2,000 m²) but with different operational lives: 8 and 3 years. Both H-SSF CWs, located in Southern Italy (Sicily), are used for tertiary treatment of the effluent of a conventional wastewater treatment plant. This study evaluates and compares H-SSF CW efficiency both in terms of water quality improvement (removal percentage) and achievement of Italian wastewater discharge and irrigation reuse limits. The mean removal percentage, for the overall operational life, of TSS, COD and BOD (80%, 63%, 58% obtained for H-SSF1 and 67%, 38%, 41% for H-SSF2), confirm the high reliability of CWs for wastewater treatment. However, despite the satisfactory removal of microbial indicators (the mean E. coli removal was up to 2.5 log unit for both beds), CWs didn't achieve the Italian limits for wastewater reuse. Information on hydraulic properties of the CWs were extracted from breakthrough curves of a non-reactive tracer (NaCl). By comparing the nominal (τ_n) and actual residence time (τ), hydraulic behaviour was revealed.

Dairy and livestock farms produce considerable amounts of wastewater, which could pose an environmental risk if not properly treated and discharged. Conventional treatment plants can represent an inadequate and costly solution in terms of operation and maintenance, especially for small and medium-sized farms. Thus, a valid and sustainable alternative can be provided by constructed wetland (CW). This paper analyzed the use of CW systems at different scales to treat dairy wastewater (DWW) and livestock wastewater (LWW) all around the world over the last thirty years. This systematic review identified 50 case studies reported in 50 publications from 22 countries: 20 CW for LWW and 30 for DWW. Per each type of WW, the analysis reported and compared the following: CW layout, type of substrates, vegetations planted, design parameters, removal efficiencies and management aspects. Gravel and sand are the most common substrates used in CW to treat both types of WW. Regarding vegetation, Phragmites australis is the most commonly used species in CWs treating LWW, whereas Typha spp. are the most frequently used in CWs treating DWW. Hybrid CW showed the highest removal performance for all parameters reported. This review can improve knowledge on CW, offering a technical and practical overview of the status of CW for treating LWW and DWW.