The water saving potential and the socio‐economic feasibility of greywater reuse within the urban sector – Israel as a case study

This paper demonstrates that on‐site greywater reuse is acceptable to the Israeli public and is an economically feasible solution for reducing urban water demand. The penetration ratio of greywater reuse in Israel was estimated at 19–31% in 2025 (population ∼10 × 106), which is equivalent to a water saving of 30–51 × 106 m3/y. The public was found to highly support the six reuse options suggested, with an overall average grade of 85%. Nevertheless, people supported public reuse more than reuse in their homes. The economic analysis showed that on‐site greywater reuse can be economically feasible especially where water prices continually increase. Under the current Israeli water and sewage tariffs an RBC‐based reuse system became economically feasible when building size reached seven storeys (26 flats). The unit cost of greywater was found to be very sensitive to the system’s size especially in the small size range.