Algae Bloom Halts Israel's Desalination Plants, Exposing Water Reserve Vulnerability

Microscopic algae, believed to have originated from the Nile, have caused significant disruptions to Israel's desalination facilities since late August, leading to the temporary shutdown of five out of six plants. These facilities supply nearly 80% of the country's domestic and urban water consumption. During the shutdown, water deficits were met by drawing heavily from Israel's already strained groundwater and the Sea of Galilee.

While the algae bloom appears to be naturally subsiding, allowing some plants to resume full operation, the incident has highlighted the precarious state of Israel's water reserves. Both of the last two winters have been insufficient in rainfall, causing the Sea of Galilee's level to drop to 213.5 meters below sea level, its lowest point since 2018 and below the "red line." Groundwater levels are also critically low, standing at approximately 1.9 meters above the red line, a stark decrease from about 5.3 meters in 2024. The rate of groundwater decline over the past year, nearly 2.5 meters, is the steepest in at least 25 years, raising concerns about potential chemical changes in the water if levels drop further below the red line.

The country's water management relies heavily on desalination for daily use, with agriculture primarily using treated wastewater. However, delays in constructing new desalination plants, such as the "Shikmon" 2 facility, which has faced a two-and-a-half-year setback due to events like the COVID-19 pandemic and the war, mean that any disruption to desalination forces reliance on these depleted reserves. The State Comptroller had previously warned in 2024 about the Health Ministry's failure to survey algal toxins from invasive species, a concern now realized.

While immediate water supply disruptions were minimal, mainly affecting agriculture and leading to compensation claims, the long-term implications are significant. Water officials hope for a rainy winter to replenish reserves, but this is not guaranteed. A public campaign to encourage water conservation is planned. If these measures fail, agricultural water consumption, which constitutes the majority of the country's water use, may be curtailed. Efforts are underway to expand the infrastructure for delivering treated wastewater to more regions, reducing reliance on potable water, though this also sparks debate over subsidized water prices for farmers.