Will Israel Flood Gaza Tunnels To Force Out Hamas? What We Know

The Israeli military is reportedly mulling an effort to flood the labyrinthine network of militant tunnels under the Gaza Strip as part of its campaign to "eradicate" the Hamas militant group.

The Wall Street Journal reported on Monday—citing unnamed American officials—that Israeli forces constructed five large water pumps near the al-Shati refugee camp in Gaza City in November, in the northern portion of the Strip already under Israeli control.

The pumps, the newspaper reported, could flood the underground network of tunnels within weeks, by pumping thousands of cubic meters of water into them every hour. Israeli officials, WSJ reported, have informed U.S. allies about their discussions, but have not yet decided whether to go ahead with the plan.

"We are not sure how successful pumping will be since nobody knows the details of the tunnels and the ground around them," an unnamed source familiar with the plan told the WSJ. "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."

Israeli authorities have not commented on the report, or on unconfirmed videos circulating on social media purporting to show the pumps under construction or in operation.

"We have no comment on this matter," the Israel Defense Forces Spokesperson's Unit told Newsweek early on Wednesday.

Israeli government spokesperson Eylon Levy told a Jerusalem Press Club briefing on Tuesday: "The IDF is of course employing a range of engineering measures, and I can't comment on the operational measures that they are using or maybe considering."

Levy told Newsweek there would be "no immunity" for militants as the IDF pushes south, regardless of international concern about the mounting civilian death toll.

Newsweek has contacted a Hamas spokesperson via WhatsApp to request comment.

The WSJ report noted potential concern among officials over the plan, including the danger of damage to Gaza's aquifer and soil if seawater and toxic substances from the tunnels seep out into the surrounding environment.

Flooding the tunnels may also imperil the 137 hostages still being held in Gaza by various groups, which have traditionally used the underground networks to store valuable assets, hold prisoners and shelter militant leaders.

Eyal Hulata, who served as Israel's national defense adviser from 2021 to 2023, told a Jerusalem Press Club briefing on Tuesday he was "happy to see creative thinking on how to resolve tunnels in ways that are less explosive, this is important."

"The water has a tendency to penetrate into the soil and back to the sea, because in the end this is land, it is not concrete at the bottom," Hulata added. "Nothing can stay there for a long time."

The extent of the tunnel network is unknown, but the IDF has previously estimated they could span some 300 miles. Some sections are reportedly as deep as 150 feet underground, and large enough to drive vehicles through.

The strategic use of the tunnels makes them a key target for the IDF. Past incursions into Gaza have focused on finding and destroying the underground networks, which have previously been used to smuggle goods into the blockaded Strip and as routes of attack against Israeli military facilities along its borders.

Israel's invasion is a broader effort, intended to collapse Hamas and remove it from power in Gaza. The IDF is now fighting its way into Khan Younis in the southern part of the Strip, the territory's second-largest city and home to Hamas' Gaza political leader Yahya Sinwar and military commander Mohammed Deif.

"We're moving south to continue erasing the whole of Hamas infrastructure in the Gaza Strip," Levy said on Tuesday. "All of its terrorist infrastructure, all of its governing infrastructure. We are going after every tunnel, every commander because the goal of this war is to totally destroy Hamas; total victory over the terror organization that perpetrated the October 7 massacre."