## 3 Results and Discussion
### Cost-Benefit Analysis of Water Reclamation Projects for the Irrigation of Plants and Green Areas
From the CBA of water reclamation projects for the irrigation of plants and green areas within industrial parks, projects are profitable for all scenarios, regardless of whether environmental benefits are included. Therefore, from the perspective of industrial parks, there are financial incentives for project implementation. Nevertheless, when including  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{ \begin{tabular}{c} **Discount** \\ **Rate** \\ \end{tabular}  } & \multicolumn{3}{c}{**240 m\({}^{3}\)/d**} & \multicolumn{3}{c}{**480 m\({}^{3}\)/d**} & \multicolumn{3}{c}{**2400 m\({}^{3}\)/d**} & \multicolumn{3}{c}{**3600 m\({}^{3}\)/d**} & \multicolumn{3}{c}{**4800 m\({}^{3}\)/d**} \\ \cline{2-11}  & **Exclude** & **Enclude** & **Enclude** & **Enclude** & **Enclude** & **Enclude** & **Enclude** & **Enclude** & **Enclude** \\ \cline{2-11}  & **EB** & **EB** & **EB** & **EB** & **EB** & **EB**  
environmental benefits, projects had higher NPVs, IRRs, and BCRs and lower PPs compared with cases excluding environmental benefits. The findings of this study are consistent with those of the CBAs of projects for the reclamation of effluents from municipal WWTPs for irrigation, recreation, and environmental purposes, which found that projects were more economically feasible when externalities such as environmental and social benefits were included [13; 15; 17]. [PERSON] et al. (2012) [15] evaluated the feasibility of using reclaimed wastewater from a central WWTP in Po Valley, Italy, for irrigation and environmental purposes. The reclamation treatment train consisted of rapid sand filtration, a horizontal subsurface flow bed, and a lagoon. The results suggested that the agricultural, environmental, financial, and recreational benefits offset the high construction costs, thereby making the project economically feasible [15]. Similarly, [PERSON] et al. (2020) [17] conducted a CBA on a reclamation project in Puglia, Italy, which reused effluent from a municipal WWTP for irrigation, and the CBA considered environmental and recreational benefits. The water reclamation units included clarification, filtration, and ultraviolet (UV) disinfection. In almost all cases, environmental benefits must be included to make a project economically feasible. [PERSON] et al. (2011) [13] conducted CBA on 13 WWTP in the Valencia region of Spain that reused effluent for environmental purposes. Their results suggested that some projects (4 out of 13) were not economically feasible when only the internal costs and benefits were assessed, whereas all projects were feasible when externalities, that is, environmental benefits, were included. However, the water reclamation system in the [PERSON] et al. study [13] was unclear and might include secondary treatment and/or membrane units, differing from this study and the studies conducted by [PERSON] et al. (2012) [15] and [PERSON] et al. (2020) [17]. Despite the differences in water reclamation facilities, the inclusion of the environmental benefits similarly improved the economic feasibility of projects. Similarly, LCA and eco-efficiency assessment have pointed to a similar direction that water reclamation for irrigation delivered economic and environmental benefits [10; 46], although the results are likely site-specific [47]. An LCA study by [PERSON] et al. (2010) [10] demonstrated that the agricultural use of reclaimed water from a WWTP located on the Mediterranean coast offers environmental and economic benefits, especially when compared to desalinated water, and that water reclamation should be encouraged when freshwater is scarce. Based on an eco-efficiency assessment, [PERSON] et al. (2021) [46] suggested that reclaimed water could be used to generate an economically profitable yield of vineyard cultivation in Acquaviva Delle Fonti, Italy while also offering net environmental benefits.