— Everywhere you look there is destruction: mosques, factories, schools, hospitals, universities and thousands of houses, many shattered into piles of bricks, glass and metal. Roads mangled by military tanks and bulldozers. Cities without electricity, pitch black at night. The main sewage plant disabled, polluting the turquoise waters of the Mediterranean.

And amid the ruins, more tragedy looms. Caught between Israeli airstrikes and Hamas mortars and rockets, entire families have been wiped out and their social safety nets destroyed. Nearly one-third of Gaza’s 1.8 million people have been forced to flee their houses, and many are now homeless. Tens of thousands of children are believed to be suffering from psychological trauma, according to the United Nations.

As a temporary cease-fire held for a second day, Palestinians are coming to grips with a deepening humanitarian and environmental crisis that threatens to affect Gaza for years. The scale of destruction and loss over nearly a month of war, Gazans and international aid workers say, is far more devastating than that left after the two previous Israel-Hamas battles, in 2009 and 2012.

“I am 70 years old, and I have not witnessed a war anything like this one,” Muhammed al-Astal said as he inspected the remains of his cream-colored house, which had been devastated by Israeli shells. “This is not war. This is eradication.”

As negotiations began in Cairo on Wednesday to secure a broader truce between Israel and Hamas, the rebuilding of Gaza emerged as a key element of a solution to the current conflict. Under discussion is an international donor conference to raise funds and the reconstruction directed by the Western-backed Palestinian government of Mahmoud Abbas, which lost control of the coastal enclave when Hamas seized power in 2007.

Billions were also spent on reconstructing Gaza after Israel’s 2008-2009 Operation Cast Lead offensive against Hamas. Back then also, schools, factories, bridges, mosques and more than 6,000 homes were badly damaged or destroyed, according to the United Nations. But five years later, many of the structures haven’t been fully rebuilt. Now, the current conflict has brought even more wreckage.

Speaking Wednesday in front of the U.N. General Assembly, Secretary General Ban Ki-moon said, “The massive deaths and destruction in Gaza have shocked and shamed the world.”

“We will build again, but this must be the last time to rebuild,” the U.N. chief said. “This must stop now. We must go back to the negotiating table.”

Palestinian officials estimate that airstrikes and shelling have wrecked at least 10,000 houses and seriously damaged 30,000 more. As many as 80 mosques have been damaged or destroyed. Many farming areas and industrial zones, filled with the small manufacturing plants and factories that anchored Gaza’s economy, are now wastelands.

“Most of the life has been destroyed,” said Mofeed Al-Hasayneh, the Palestinian government’s Gaza-based minister of public works and housing, adding that it could take “seven to eight years” to rebuild the houses and other structures without assistance from the world.

Even international relief organizations, accustomed to working in hard-hit war zones, have expressed shock at the scale of the damage.

“I’ve never seen such massive destruction ever before,” Peter Maurer, the president of the International Committee of the Red Cross, said in a tweet Tuesday after visiting Gaza.

Children paying a terrible price in Gaza

With the lull in the conflict, aid agencies are scrambling to assess the damage and determine how best they can help, if the cease-fire holds.

On Tuesday, aid worker Mathieu Ebbesen-Goudin arrived with his team in the eastern Showka enclave of Rafah, near the Israeli border, where vegetable and fruit farms have been obliterated. Israeli tanks were visible across the border, throwing up dust. Israeli forces pummeled the area last week when they searched for a soldier apparently abducted by Hamas fighters but who Israel later said had died in battle.

“The harvest for this year is lost. We have to rehabilitate all the lands,” said Ebbesen-Goudin, head of mission of Première Urgence, a French relief agency. First, though, the farms needed to be cleared of unexploded ordnance, he added, which could take months, even a year. The farms produced potatoes, tomatoes, zucchini, olives and oranges, mostly for domestic consumption.

Even before the war, Gazans lived precariously, particularly since Israel imposed an economic blockade of the strip after Hamas took control. Now, many families have fallen over the precipice, losing farms, livestock and their homes.

“There is going to be a strong economic impact,” said Ebbesen-Goudin.

Moussa Abu al-Rous, 45, could already see his future as he stood in the rubble of his flattened house near Rafah. His one-acre farm, where he had olive and orange trees, is now a field of bulldozed dirt. Rous, who has six children, said he doesn’t know how he will pay for his son’s college education or take care of his family.

“How am I going to feed them?” Rous said. “The winter is coming. Where are we to live?”

In Gaza City, Ali al-Hayek, the head of the Palestinian Businessmen Association, went to inspect dozens of factories, particularly those in the border areas where most bombardments and clashes occurred. He said that 100 to 120 factories, including some that produced medicine, were destroyed.

“Thousands of workers used to work in these factories,” said Hayek, shaking his head.

Gazan children are also facing a grim predicament. The United Nations says 138 schools have been damaged by shelling. More than 250,000 Palestinian evacuees are sheltering in U.N.-run schools, making it unlikely classes will be able to start this fall. The U.N. Children’s Fund estimates that about 400,000 children are in need of psychological therapy.

The knock-on effects of the conflict are visible everywhere. An Israeli strike on the enclave’s primary power plant caused electrically driven water pumps to stop functioning, forcing people to wait in lines to get potable water for domestic use. Fuel prices have shot up, driven in part by Palestinians with generators seeking fuel that was already in short supply.

And then there is the serious damage to Gaza’s main sewage treatment plant, threatening to bring diseases caused by poor sanitation and an environmental disaster.

On Tuesday, the stench was overpowering. Flies were everywhere. There were only two technicians at the desolate plant, which needs electricity to treat wastewater and pump it into the sea.

In addition, airstrikes also damaged a pipeline, the technicians said. Even if the electricity returns, the German-built plant will take months to repair, say aid workers.

“Now, 55,000 cubic meters of sewage is being sent every day into the sea without treatment,” said Saeed al-Heeki, one of the technicians.

Aid workers warn that even if the international community funnels in the billions of dollars needed to rebuild Gaza, the money will not make a long-term difference unless there is a durable peace between Israel and Hamas.

“If there’s not a political solution, we will reconstruct and in two years you will have another war,” said Ebbesen-Goudin. “And Gaza will be destroyed again.”