By John — Desalination News
Israel’s water authorities are now warning that the algae-driven desalination crisis could persist for several more weeks, a sharp reversal from the more upbeat tone officials struck earlier in the disruption. The concern comes as the bloom drifts northward toward Hadera, the only major coastal plant that has kept running at full capacity throughout the episode, and as a closely watched offshore treatment experiment has yet to produce a public result.
Algae Moving North, Threatening the Last Plant Standing
Israel Oceanographic and Limnological Research and the Water Authority say the microalgae responsible for the shutdowns is now spreading north along the coast, raising the possibility that Hadera — which has absorbed a disproportionate share of the country’s desalination load while Ashkelon and Ashdod remain offline — could itself be knocked offline. Losing Hadera would leave Israel without a single fully functioning large-scale Mediterranean desalination plant for the first time since the crisis began in late August.
In response, researchers are testing an unusual approach: rather than trying to kill or disperse the algae, they are examining whether encouraging it to grow into larger clumps would let pretreatment filters trap it before it reaches the reverse-osmosis membranes, rather than letting the smaller cells slip through.
Optimism Fades as Copper Treatment Results Stay Unpublished
Energy Minister Eli Cohen said last week that the shutdown was “largely behind” Israel and that the system would soon return to normal. That confidence has since cooled. The Water Authority has not released results from an aerial operation, first reported by Calcalist, in which planes dispersed copper-containing compounds off Ashkelon to try to break up the bloom; officials had promised results within about 48 hours of the operation, which took place more than a week ago. Ashkelon and Ashdod remain shut, and Palmachim and the two Sorek plants continue running at reduced capacity to protect their reverse-osmosis membranes from premature fouling, a concern serious enough that the state is now funding a dedicated stockpile of replacement membranes.
A Warning Officials Had Two Years to Act On
Adding to the pressure on the Water Authority, it has emerged that a parliamentary subcommittee held a hearing in May 2024 specifically on marine contamination risks to desalination plants, at which the Authority’s own desalination division head described the scenario that has now unfolded. According to that hearing’s record, no significant preparatory measures were taken in the two years that followed. The disclosure lends weight to arguments, raised by water-policy experts in the days after the shutdown began, that Israel’s near-total reliance on a handful of coastal plants left the system with too little backup capacity.
For now, the Water Authority says the national system remains stable, with household and agricultural supply sustained by increased pumping from the Sea of Galilee, groundwater wells, and reservoirs replenished by Mekorot over the past week. But with algae moving north and no confirmed fix in hand, officials are no longer putting a firm end date on the disruption.