“Forty per cent of household water can actually be reused,” says Ilan Katz, managing director of Water Arc, a new initiative to reduce the demand for water in urban areas. So-called “grey-water” includes waste water from showers, washing machines and bathroom sinks which can be reused for flushing toilets, which accounts for around 35% of the total water used by an average Israeli household, as well as watering plants and gardens. Katz told Green Prophet that grey water can be treated with relative ease and be reused without the odour or colour typically associated with sewage.
Katz admits that Water Arc’s grey-water recycling systems are “not economical” for private houses (retailing at NIS 15,000 for a villa), but can represent both a cost-effective and environmentally sustainable solution for larger dwellings. For instance, Katz estimates it would take four years to realised the investment of around NIS 100,000 needed to incorporate grey-water recycling into a 100-unit apartment block, saving 50 to 70 shekels per person each month.
Whilst Water Arc has just been launched, another Israeli firm, Ecosystems, has already helped 80 families in the country to recycle grey-water although they are frank that most of the take-up so far has been “people with an ideological mindset” since their their systems are currently not economical. But Katz is optimistic for the future: “We haven’t started yet, but we believe that the demand is out there.”
See also Ayala Water and Ecology