Jeff Goodson: Flood the Gaza tunnel system

Sunset over the Israel-Gaza war zone, via Reuters live stream video.


The biggest problem confronting Israel in its war on Hamas is how to destroy the Gaza tunnel networks and the terrorist operations therein.  Bombing works—mostly—but there’s a better way. Not only would it dramatically reduce Israeli military and Gazan civilian casualties, but it would effectively destroy the tunnel systems for the long term. That solution is to flood the tunnels with seawater from the adjacent Mediterranean.

I worked on the Gaza Strip back in the 1990s. The U.S. government was pouring tens of millions of tax dollars into development assistance there on engineering infrastructure, housing, and related projects. Part of reviewing that work on the ground involved tramping over much of the small territory on foot.

Gaza consists of a strip of beach, back beach, and coastal plain that’s flat to slightly rolling.  The territory stretches for about 25 miles along the eastern Mediterranean. At its widest, in the south, it’s about seven and a half miles wide; most of it is far narrower, about half of that.

The Gaza tunnel system, mostly constructed over the last forty years, provides Hamas with offensive access to Israel.  It also constitutes the terrorist organization’s most formidable defensive redoubt.  The tunnels present by far the most difficult logistical problem for Israel in eliminating enemy targets. Open-source maps show at least 11 independent tunnel networks, some nearly adjacent to the sea.  The number of independent networks, however, could far exceed that.  Hamas claims that the total length of the tunnels is about three hundred miles.    

The geography of Gaza argues strongly for the stratagem of flooding the tunnels. It would force the enemy above ground where they can more easily be destroyed, dramatically reduce the Israeli casualties required to accomplish that task and resolve the problem of dealing with parts of the tunnels that are too deep to destroy through bombing. Most importantly, flooding is a permanent or near-permanent solution to the Gaza tunnel problem. Once accomplished, pumping them out enough to be usable again would be both extremely costly and—especially in conjunction with bombing—exceptionally difficult.  The timing of executing a flooding strategy is flexible; some could be flooded now, others later, and still others once they’re discovered. 

The engineering is straightforward. Egypt flooded 37 cross-border tunnels in southern Gaza back in 2015 in what stands as a practical proof of concept in this location. Seawater from the Mediterranean would be pumped directly into the tunnel openings through short pipelines. While there’s little hydrological head, there is also little topographical relief to deal with in laying the pipe. Large volumes of water are pumped long distances every day, and Israeli water technology is world class. 

The shortest and most direct route to the tunnel entrances would be directly from the Mediterranean.  This would require kinetic clearing of the construction sites and holding them for the duration of the operation to protect the temporary water transmission lines. The distance that would need to be cleared and held could be minimized on the northernmost and eastern tunnels by running a trunk line through adjacent Israeli territory and feeding water distribution lines to the tunnel entrances off that. 

Flooding doesn’t have to be slow. A six-by-five-foot tunnel that runs 300 miles is a huge volume to fill, but how fast it fills depends on how fast the water is pumped. Rough calculations indicate that if a single pipe were used for each of 11 tunnels, with each pipe pumping at a very conservative 100 gallons per minute, it would take about seven and a half months for all 11 tunnel networks to fill. Pumping water at 10 times that rate, however, is routinely done today everywhere from wastewater treatment plants to oil field operations. Also, the tunnels wouldn’t have to be filled to capacity to generate the desired effect.  The effect would begin as soon as water started to flow; by the time a tunnel has two or three feet of water it would be effectively unusable.  

The collateral damage to infrastructure should be minimal. The distances are short, the diameter of the required pipe is small, and the pipelines would run very close to the surface. As with the Egyptian tunnel operations, the impact of flooding on groundwater salinization would no doubt be raised. The extent of saltwater leakage through the tunnels into local groundwater would depend on the depth and construction of the tunnels and the configuration of the local aquifer. Gaza’s shallow aquifer is already over-depleted, however, and 95% of its groundwater was considered unfit for public consumption as far back as 2017.  The reason is that it’s extensively contaminated with chemicals and sewage, as well as saltwater intrusion from the Mediterranean due to a long history of over pumping. Because of that, Gaza relies heavily on desalinization for potable water.    

In the short term, think of flooding Gaza’s tunnels as humanitarian assistance. By eliminating the need to keep bombing them, flooding would reduce civilian casualties and other collateral damage.  In the long term, think of denying Hamas access to the tunnels as an A2AD stratagem. At the end of the war, there can be no complete destruction of Hamas, nor long-term peace out of Gaza, unless and until the Gaza tunnels are taken out.

Jeff Goodson is a retired U.S. Foreign Service officer. In 29 years with the U.S. Agency for International Development, he worked on the ground in 49 countries in Africa, Asia, Latin America, Eastern Europe, and the Middle East, including the Gaza Strip. He served 31 months during three tours in Afghanistan. From 2006-2007 he was Chief of Staff and Head of Civil-Military Planning and Operations at USAID/Kabul, and from 2010-2012 he served as the DCOS/Stability Director of Development at ISAF Headquarters.

This article was originally published by RealClearDefense and made available via RealClearWire.


  1. Waiting for someone to claim that it would only make global warming worse, and we should import another million or two refugees by commercial jet instead.

  2. Excellent Idea! Might also want to stuff a herd of Hogs in the tunnels prior to flooding the tunnels with Sea Water as well as Bentonite (this should harden-up like concrete). The purpose for this would be to discourage more tunnel boring activities, something like a deterrent.

  3. Aren’t we all tired of Zionism? I know they own you guys but seriously have some dignity, you’re embarrassing America. Zionists push for multiculturalism in our nation and ethnic homogeneity in theirs. Zionists did 9/11, everyone knows it. You think Zionists care about you? They care as long as you are sending money, that’s why they buy our politicians (with our own money). Anyone who’s been in American politics knows this already, they all grovel before AIPAC before they are allowed an office lol. The political class doesn’t seem to realize none of this is a secret and people don’t like it.

    • We are, but zionism is so deeply embedded in every facet of western culture that exposing things like US states buying hundreds of millions of dollars of Israeli government bonds while these states are in debt crises gets called anti semitism

    • Nat, I am glad you learned a new word and are using it in a sentence or two. Now do you actually KNOW what it means?

      Your historical illiteracy is somewhat disturbing, when you forget that Palestinians were offered a state back in 1948. The entire region was a British possession, which described any and all living in that region as Palestinians, Jewish and Arab alike. It is confusing when you equate Muslim terrorists with the Jewish State or imply that Hamas terrorists care more about the average American than the Jewish people. Last I checked I never heard Israelis chant “Death to America” but have seen it plenty of times from Hamas, Hezbollah, Palestinians, Iran….

  4. But if they do that how can the manufactures of munitions, suppliers of body bags, companies that build new buildings make any money ?.

  5. I remember flooding gophers out of holes in the yard with a garden hose, they make awfully big pumps nowaday and hoses that can be set up in not time to rid the yard of vermin.

    Problem is they will keep doing what they are currently doing and using human shields to protect themselves amongst a population that by and large welcomes the human sacrifice.

  6. If the tunnels are already fitted with drains and sumps, flooding will be ineffective. The Israelis already know.

  7. Didn’t Israel create Hamas in the first place to defend against Russia? And Israel’s border is so well protected a cat couldn’t even get through undetected, so why was it left open for Hamas?

    • Sharon,
      Thats a good question.
      Why was all the intelligence signals ignored?
      Why did Biden give Iran money?

    • Egypt has been pressuring Isreal to let more and more Palestinians into Isreal for work. So they being a Free Nation they permitted More Palestinians seeking work into Isreal.

    • Egypt and Jordan kingdoms they refuse to increase Palestinians immigrating into their countries for fear Hamas fighters will be among the immigrants. They don’t want terrorists in their country threatening their established government order and assassinating Egypt and Jordanian leaders.

    • Sharon, I could only find one article in the Washington Post from 2014 to make that claim. Reading this piece it seemed to intimate that Israel supported Hamas against Arafat’s PLO, probably in a “the enemy of my enemy…” scenario similar to the US supporting Afghan fighters against Russia. If this is accurate I can not ascertain and given the source, I am skeptical.
      It is further interesting that you completely dismiss the entire premise of this article. Infiltration into Israel from the Palestinian/Hamas controlled territory via a vast network of tunnels. Just like US border patrol fighting smugglers at the southern border, vast networks of tunnels change all the time and require constant vigilance. Your implication that Israeli leaders “invited” this slaughter is preposterous and lacks ANY proof.

  8. Its either flooding or carpet bombing. Ratheon and the Pelosis wont like the hit on their stock portfolio but it sure is easier on the environment.
    Just sit at the exit and pick them when their head pops.

  9. Good news, bad news associated with flooding the tunnels. Gaza gets its water via an aquifer under it. Sadly, that aquifer has already been somewhat trashed by lack of attention by Hamas and others in Gaza. Flood the tunnels, and you trash the aquifer completely. Solution is to provide water desalination to remaining Gaza residents. At least, they can’t use that to build tunnels with. Solution? Yes, though not a direct one without collateral impact. Cheers –

  10. Ten , 10 inch submersible flygt pumps will move 200,000 gallons of water per minute through a rubber discharge hose . One pump will sit on a normal wood pallet . These pumps are readily available . However not built by Grumman or Boeing ! If one of these company’s buys Flygt pump company , they’ll be C-17 loads headed to Mid East !

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