Israel halted supply of water to Gaza amid ongoing desalination crisis
Nir Hasson reports in Haaretz on 2 September 2026:
Israel’s national water company Mekorot halted the flow of water to Gaza on Tuesday, amid a crisis affecting Israel’s desalination facilities, leading to nearly one million people in Gaza suffering water shortages on that day as a result of the decision, according to UNICEF. The disruption left nearly one million Palestinians in Gaza facing water shortages, UNICEF said.
About one-third of Gaza’s current water supply comes from Israel, while the remainder is produced through groundwater pumping and desalination facilities in the Gaza Strip.
Five of Israel’s six desalination plants were shut down Tuesday for the second time in days after unusually murky seawater along the Mediterranean coast made the water unsuitable for desalination, cutting off about 80 percent of the country’s desalinated water supply.
In response to the shortage, humanitarian organizations increased pumping and desalination efforts, and only on Wednesday afternoon did the supply from Israel partially resume.
Experts and environmental organizations believe that sewage flowing from Gaza into the sea is one of the factors disrupting the operation of Israel’s desalination facilities.
Throughout the war, Israel has caused extensive damage to Gaza’s water and sewage infrastructure. Nearly all of the strip’s desalination facilities, pumps, wells and water-piping systems have been damaged, destroyed or put out of service.
In 2025, Gaza’s water supply collapsed completely, leaving most residents dependent on water trucks operated by aid organizations. The shortage of clean water was a major factor in worsening the humanitarian crisis in the Strip, particularly in camps for displaced Gazans, and contributed to the spread of hunger and disease in the enclave.
Very little sewage then flowed out of Gaza due to the water shortage, and wastewater amassed near residential areas. Therefore, pollution generated in displacement camps and Gaza’s cities largely did not make its way into the sea.
After the cease-fire started in October 2025, Gaza’s water network was partially restored, and that along with international pressure on Israel to resume its supplying water to the strip increased the amount of water available to Gaza’s residents – and, in turn, the volume of sewage flowing into the sea. The flow was also exacerbated by tanker trucks operating in Gaza, which pump sewage from cesspits and discharge it into the sea.
Last November, the environmental organization EcoPeace Middle East warned the U.S. Civil-Military Coordination Center that marine pollution off the Gaza coast could also affect Israel. The organization says Israeli officials ignored the warnings.
“With the declaration of the 2025 cease-fire, it was clear that priority should be given to the Board of Peace restoring Gaza’s sewage infrastructure, rather than allowing the issue to become hostage to broader political disputes,” the organization said in a statement. “Although we understand that Israel’s Water Authority supported our position, government ministers ignored the warning, despite the basic fact that pollution does not recognize borders,” it added.
Efforts are underway in Gaza to address the situation. UNICEF said it is working with partners “around the clock to get the Sheikh Ajleen sewage treatment facility up and running again. Before it was damaged in hostilities, it used to serve 700,000 people in southern Gaza.”
“All six wastewater treatment plants in Gaza have shut down as a result of hostilities and 70 per cent of sewage pumping stations are out of service. Every day, more than 150,000 cubic metres of untreated wastewater is discharged into the environment, increasing the risk of disease and contamination,” UNICEF said.
The organization also warned that Israel must allow the entry of equipment needed to rehabilitate Gaza’s sewage infrastructure into the Strip, including generators and solar energy systems, to ensure that the sea does not become polluted.
Israel currently prevents such equipment from entering the Gaza Strip, arguing it could be used by Hamas for military buildup.
Microalgae
Israel’s desalination crisis began Monday following a sudden increase in the Mediterranean’s turbidity – a measure of ocean’s murkiness, caused by tiny particles filling the water. Officials say it’s currently being caused by an increase in microscopic algae, possibly originating in waters near Egypt. The algae pass through the filters of desalination plants, but then may clog their inner workings.
Experts trying to determine the cause of the algal bloom are still uncertain whether there’s a link to pollution from Gaza – but many haven’t ruled out the possibility.
Satellite imagery analyzed by Satalize found that the algal bloom began in the Nile Delta, apparently caused by a species of algae carried there by the river’s currents. Scientists who spoke to Haaretz, however, said that nutrients flowing into the sea in sewage discharged from Gaza may have contributed to the unusual bloom and to the algae’s northward movement from the Sinai coast toward Israel. “Algae need something organic to feed on, and sewage can definitely cause that,” said Adi Ronen of Satalize. “But it’s not 100 percent.”
Professor Emeritus Jack Gilron, from the Zuckerberg Institute for Water Research at Ben-Gurion University of the Negev, cited several factors that likely combined to cause the disruptions. According to him, the disruptions began with the release of microalgae at the mouth of the Nile, combined with ocean currents and weather conditions that carried them toward Israel’s shores.
“Two additional factors made the problem worse,” he said. “The first is water temperature – the warmer the sea, the faster the growth rate. The second is the discharge of raw sewage near Gaza, which contains nutrients that serve as sustenance for the algae. All of this intensified the bloom. It was the perfect storm.”
“It is difficult to say what the single source of the phenomenon is,” agrees Dr. Tamar Guy-Haim, a researcher at the Israel Oceanographic and Limnological Research Institute. “It certainly did not begin along the Israeli coast or in Gaza, but farther south. However, we can’t rule out additional contributions from nutrients enriching water from various sources.”
Dr. Youval Arbel, coast and marine campaigner at the environmental organization Zalul, supports her assessment. “The fact that the bloom began off the coast of Egypt doesn’t contradict the possibility that sewage from Gaza contributed to it. The microalgae from the Nile Delta wouldn’t have survived and proliferated without the sewage from Gaza. Sewage discharges change the picture.” Arbel also warned: “It is time for Israel to understand that if sewage in Gaza isn’t treated, we will eventually have no water here in Israel.”
Unusual weather conditions in the region over the weekend may have also helped carry the algae northwards. Scientists estimate that the Mediterranean Sea’s unusually high temperature, driven by global warming, also contributed to the exceptional algal bloom.
“Beyond the immediate factors behind this week’s event, discharging wastewater into the sea, along with climate change warming waters, encourages microalgae growing and spreading across the region,” Arbel said. “Climate change is also intensifying these events, making extremities much more frequent than before,” he stressed.
Researchers at the Israel Oceanographic and Limnological Research Institute have been working on Wednesday to genetically sequence the algae, to better understand its origins and why it spread.
“I have worked in the Mediterranean for a long time, and I have never seen anything like this,” said Or Bialik, a researcher at the institute. He said that on Tuesday evening he went out by boat to collect samples off the coast of Palmachim. “We were surrounded by green water, like being in a lake. The turbidity was so severe that you couldn’t see the equipment after half a meter. We also saw some dead fish floating on the surface,” he said.
Israel’s Energy and Infrastructure Ministry has not yet responded.
This article is reproduced in its entirety