10/21/2012 14:44–While Israel’s authorities allow almost no decentralized water systems, experts stressed that there would be a place for such structures – particularly greywater recycling mechanisms – in the country’s future, at a conference in the Negev last week.
The third Sde Boker Conference on Advanced Water Management Technologies was held at Ben-Gurion University Sde Boker campus.
Other highly developed countries, such as the United States, Australia and Germany, allow at least to some extent the reuse of household greywater, but the Health Ministry still takes issue with such practices due to fears of health risk, according to Prof.
Amit Gross, of the Environmental Hydrology and Microbiology Department at BGU’s Zuckerberg Institute for Water Research.
While Israel reuses a higher proportion of treated wastewater than any country by far – more than 80 percent – and its desalinated water industry also thrives, all of these mechanisms are performed in a centralized, large-scale form. Decentralized greywater reuse, on the other hand, would mean individual homes reusing sink and shower basin water to flush their toilets and water their gardens, experts explained.
“In Israel we neglect almost completely the discipline of decentralized water treatment,” Gross said.
To put it simply, blackwater is defined as feces with flushing water and urine, yellowwater is urine with or without flushing water, brownwater is feces with flushing water without urine, and greywater is other domestic sewage – such as used shower or sink water, Prof. Jörg Londong of the Bauhaus-Universität Weimar said.
Londong spoke of projects in Germany and Switzerland where waste products are being separated into streams right from the home – deriving nutrients such as nitrogen, phosphorus and potassium from urine, organic content for biogas and fertilizer from feces, and reusable water from greywater. The ideal situation, he said, would be “using everything, not just water but the nutrients.”…Read More>>