WASHINGTON — The U.S. military-built pier to carry humanitarian aid to Gaza will be dismantled and brought home, ending a mission that has been fraught with repeated weather and security problems that limited how much food and other supplies could get to starving Palestinians.

Vice Adm. Brad Cooper, deputy commander at U.S. Central Command, told reporters in a Pentagon briefing Wednesday that the pier achieved its intended effect in what he called an “unprecedented operation.”

As the U.S. military steps away from the sea route for humanitarian aid, questions swirl about Israel’s new plan to use the port at Ashdod as a substitute. There are few details on how it will work and lingering concerns about whether aid groups will have enough viable land crossings to get assistance into the territory besieged by war between Israel and Hamas.

Cooper said the Ashdod corridor will be more sustainable and has already been used to get more than a million pounds of aid into Gaza.

“Having now delivered the largest volume of humanitarian assistance ever into the Middle East, we’re now mission complete and transitioning to a new phase,” said Cooper. “In the coming weeks, we expect that millions of pounds of aid will enter into Gaza via this new pathway.”

He said 5 million pounds of aid in Cyprus is awaiting transit to Ashdod, and they expect delivery to start “in the coming days.”

Sonali Korde, assistant to the administrator of the U.S. Agency for International Development’s Bureau for Humanitarian Assistance, told reporters that aid groups have confidence that “Ashdod is going to be a very viable and important route into Gaza.”

But, she said, “the key challenge we have right now in Gaza is around the insecurity and lawlessness that is hampering the distribution once aid gets into Gaza and to the crossing points.”

Israel controls all of Gaza’s border crossings and most are open.

Critics call the pier a $230 million boondoggle that failed to bring in the level of aid needed to stem a looming famine. The U.S. military, however, has maintained that it served as the best hope as aid only trickled in during a critical time and that it got close to 20 million pounds of desperately needed supplies to the Palestinians.

President Joe Biden, who announced the building of the pier during his State of the Union speech in March, expressed disappointment in the pier, saying, “I was hopeful that would be more successful.”

Planned as a temporary fix to get aid to starving Palestinians, the project was panned from the start by aid groups that condemned it as a waste of time and money. While U.S. defense officials acknowledged that the weather was worse than expected and limited the days the pier could operate, they also expressed frustration with humanitarian groups for being unable or unwilling to distribute the aid that got through, only to have it pile up onshore.

A critical element that neither the aid groups nor the U.S. military could control, however, was the Israeli military operation in Gaza that put humanitarian workers in persistent danger, and in a number of cases cost them their lives.

As a result, the pier operated for fewer than 25 days after its installation May 16, and aid agencies used it only about half that time due to security concerns.

Even at the start, officials warned of challenges because the sea is shallow, the weather is unpredictable and the area an active war zone.

The U.S. also had to train Israeli troops and others on how to anchor the pier to the shore because no U.S. troops could set foot on Gaza soil, a condition Biden has imposed since the beginning of the Hamas-Israel conflict in October.

However, enough aid to feed 450,000 people for a month flowed through the pier, according to USAID, which coordinated with the United Nations and others to get supplies to people in need.