Israel Over-Relies on Expensive Desalination, Ignores Cheaper Water Reuse

Israel, long proud of its water management prowess including national water carriers, advanced wastewater recycling, and large-scale desalination, is facing a "desalination crisis" that highlights a dangerous over-reliance on this single, expensive solution. The country has become addicted to costly desalination plants, which consume vast amounts of energy, occupy significant land, and contribute to pollution, while neglecting a more economical and readily available option: reusing "greywater" already within homes.

Greywater, comprising water from showers, baths, and sinks (excluding toilet flushings and kitchen waste), constitutes about 30% of household water consumption. Simple technological treatment allows it to be used for flushing toilets and irrigating gardens, both public and private. This could save up to 40% of potable water usage, reduce the strain on sewage systems and treatment plants, and avoid using expensive desalinated water for non-potable purposes. Despite its potential, greywater reuse is currently prohibited in Israel, leading to a stalemate due to regulatory inaction.

The Ministry of Health has raised concerns about direct contact with non-potable water, but a 2014 inter-ministerial committee failed to reach a consensus, leaving the issue unresolved. This prohibition pushes the practice into an unregulated, potentially unsafe, black market, with an estimated 10,000 homes already employing such systems without oversight. The article argues the choice is not between risk and no risk, but between unregulated and managed risk, citing the successful regulation of elevators as a model.

Implementing a regulated system for greywater would involve establishing clear rules, standards for purification and safety, and oversight mechanisms, similar to the elevator industry. This would require the Ministry of Health and the Standards Institution to set guidelines, with certified technicians and independent inspectors ensuring compliance. Such a framework could save billions, create thousands of technical jobs, and provide a legal, safe avenue for water conservation.

Pilot projects in Ganot Hadar and a planned initiative in Tel Aviv's Sde Dov area demonstrate the feasibility of greywater reuse for public landscaping. While agricultural water needs will grow, urban consumption is projected to increase far more dramatically with new housing developments, necessitating upgrades to sewage treatment plants. The article concludes that Israel needs a multi-pronged approach, integrating desalination, recycled wastewater, and greywater reuse, rather than neglecting the latter, which remains off the national agenda despite its availability in every shower.