According to a report published by the Wall Street Journal, the Israel Defense Forces (IDF) finished assembling at least five massive seawater pumps roughly one mile north of the Al-Shati refugee camp around the middle of November. These five pumps can draw thousands of cubic meters of water from the Mediterranean Sea per hour into the tunnels, flooding them within a matter of weeks.
It should be noted that Israel has not yet gone through with this plan. According to the Wall Street Journal that uncovered these seawater pumps, Israel first informed U.S. officials of the option to flood the Hamas tunnels in early November, prompting a long discussion regarding the feasibility of the plan and its possible effect on the environment against the military value of disabling the tunnels.
Another concern is the possibility that some of the remaining 140 or so hostages still being held by Hamas could be held in some of the underground tunnels the IDF plans to flood.
There is also a concern that the flooding process could take weeks, and by the time they've been fully flooded Hamas could be long gone, along with any of the hostages in the tunnels.
"We are not sure how successful pumping will be since nobody knows the details of the tunnels and the ground around them," said one person familiar with the plan who spoke anonymously with the Wall Street Journal. "It's impossible to know if that will be effective because we don't know how seawater will drain in tunnels no one has been in before."
Environmental experts warn that the IDF's plan could deprive Gaza of its only local supply of freshwater for generations to come. (Related: Without fresh water, Palestinians trapped in Gaza forced to wash, bathe in polluted Eastern Mediterranean Sea.)
Following the outbreak of the conflict on Oct. 7, Israel turned off three pipelines that carry drinking water into the Strip. Gaza's remaining water supply comes from a shallow aquifer that runs parallel to the Mediterranean coast. This aquifer has been overpumped over the years and the subterranean water levels have dropped so far that seawater has already started entering the aquifer and mixing with what little usable water remains in there.
The aquifer's water quality has also been eroded by sewage and agricultural chemical runoff, to the extent that around 97 percent of the freshwater in Gaza no longer meets the World Health Organization's water quality standards.
Eilon Adar, a professor emeritus at the Zuckerberg Institute for Water Research at Ben-Gurion University of the Negev in southern Israel, warned that flooding the tunnels could further cause ecological damage to Gaza's aquifer.
"The negative impact on groundwater quality would last for several generations, depending on the amount that infiltrates into the subsurfrace," warned Adar.
Israel would hardly feel the effect, since the coastal aquifer is replenished by water coming in from Israel into Gaza. Nevertheless, Adar said that even Israelis should "hesitate about destroying a massive natural resource."
"As a citizen, despite the disaster that we experienced on Oct. 7, I still think that in the long run – and we have to think of the future – it would be politically and morally incorrect to have a thirsty neighbor," said Adar.
Watch this clip from Fox News reporting that the IDF has discovered more than 800 tunnel entrances in northern Gaza alone.