The Israel Defense Forces is tackling the threat posed by tunnels that Hamas builds from Gaza into Israel by constructing a massive barrier. The project, estimated to cost 3 billion shekels ($833 million), will include a concrete wall fitted with sensors and reaching dozens of meters deep into the ground and standing six meters high from ground level.

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Southern Command chief Maj. Gen. Eyal Zamir told reporters on Wednesday that building the barrier could cause an escalation, but said the army will continue building the barrier even if Hamas targets the work there.

“I think the other side will have to reevaluate the situation in view of the barrier’s construction,” he said. “If Hamas chooses to go to war over the barrier, it will be a worthy reason (for the IDF) to go to war over – but the barrier will be built.”

In recent months Israel has set up concrete factories on the Gaza border, brought foreign laborers and contracted companies to flatten the area around the border and build sand mounds to protect the workers.

Open gallery view Work on Israel's anti-tunnel barrier on the Gaza border, 2017. Credit: Amir Cohen / Reuters

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Currently work is in progress at six points along the border, with workers from Spain and Moldova, African asylum-seekers and Israelis. Each month another point is added. By October some 1,000 workers will be working on the project at 40 sites 24 hours a day except Saturday, IDF sources said.

The IDF is moving the entire border area a few hundred meters east, into Israeli territory. The current fence will be strengthened and improved, and to its east a six-meter-tall metal wall will be built. Between the old and new walls several mounds of earth will be built, to enable tank deployment and patrol roads both east and west of the barrier. The roads will enable troop movements and barrier maintenance.

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The defense establishment hopes the underground concrete barrier will eliminate the threat posed by Hamas tunnels entering Israel. Sensors installed inside the barrier will sound an alarm if anyone approaches it and warn Israel of any future tunnel digging.

The barrier’s construction is also aimed at destroying the existing tunnels near the border. The army is using a huge drilling machine that crushes anything in its path to a considerable depth. This is expected to destroy the tunnels currently crossing the border from Gaza to Israel.

After that, the drilled area will be filled with bentonite, a mineral that turns viscous and adhesive in contact with water. If the drilling machine reaches a tunnel, the mineral will spread along it and the IDF will know that a tunnel has been located.

Then come the iron cages

Afterward large iron cages containing water-resistant pipes with sensors will be inserted into the ground as foundations. Once the underground barrier is built, a six-meter-high metal wall will be built on top of it to prevent anyone from crossing the border above the ground.

The IDF administration in charge of the border area says the cost of a kilometer of the underground barrier is estimated at 40 million shekels, while the cost of a kilometer of metal barrier is estimated at about 1.5 million shekels.

A number of civilian construction companies have won the Defense Ministry’s bid to take part in the border project, which also includes situation rooms to monitor the area and firing positions.

In addition, the IDF is planning to build an underwater barrier and a breakwater a few kilometers long in the sea on the Gaza border, IDF sources said.

Zamir said the border barrier could lead to escalation, but that the Southern Command intends to keep the calm in the region while completing the barrier’s construction.

Zamir showed reporters pictures of sites in Gaza, some of them civilian, which Hamas is believed to be using as tunnel shafts. He warned that any civilian who allows terror organizations to use his property for military purposes is risking his life, his family’s life and his property. For example, he showed a house in the Beit Lahiya area, which the army says has an entrance to an underground tunnel that is also connected to a mosque. Another structure, near the Shati refugee camp, has an entrance to a network of tunnels.

“Great effort is being made to locate Hamas structures used for military activity to serve us in the next fighting round,” Zamir said. “From our point of view, at a time of emergency, these houses will become targets. Anyone who happens to be in a house that has an underground infrastructure is putting his life in danger. We aim to turn it into a death trap,” he said.

“If Hamas thinks it has immunity by building a military infrastructure in a civilian environment – it’s wrong,” he said.