Three massive temporary shelters that have housed 7,700 unaccompanied immigrant youths at military bases in California, Oklahoma and Texas will close in the next eight weeks, government officials announced Monday.

The U.S. Department of Health and Human Services’ Administration for Children and Families opened the shelters in May and June to help house an influx of more than 57,000 unaccompanied minors who have crossed the southern border since October, twice the number last year, mostly from Central America.

“We are able to take this step because we have proactively expanded capacity to care for children in standard shelters, which are significantly less costly facilities. At the same time, we have seen a decrease in the number of children crossing the Southwest border,” said a statement from department spokesman Kenneth Wolfe.

He said the shelter at Ft. Sill, Okla., which housed up to 1,200 people, is expected to close by Friday. The other two — for up to 1,200 people at Joint Base San Antonio-Lackland in Texas and up to 600 people at Naval Base Ventura County — will close in the next eight weeks, he said.

Instead of being sent to the bases, children apprehended on the border will be placed in about 100 smaller standard shelters and added “surge capacity” shelters, although Wolfe noted that the military bases could reopen if the flow increased again.

“There remains substantial uncertainty about the future flows of unaccompanied children,” he said. “The three temporary shelters on military bases could be reopened for a limited time if the number of children increases significantly.”

Once unaccompanied Central American youths are apprehended at the border, by law they must be turned over by the Border Patrol to the Health and Human Services Department within 72 hours.

They are then held at shelters until Health and Human Services can place them with sponsors, usually parents or relatives, whom they stay with until their immigration cases are resolved.

The average amount of time it takes to place youths with sponsors has decreased during the last month from 35 to 30 days, Wolfe said.

Those who work with the youths cheered the base shelter closures, saying the minors fared far better in smaller, less institutional shelters where they have more access to lawyers and other advocates. Some communities have protested opening such shelters in recent weeks, successfully blocking them. But there are still enough shelters to house those coming now, advocates said.

“If you can get as many kids into the traditional shelters, the better. It’s a much more pleasant environment for a child,” said Eric Tijerina, associate director of the immigrant children’s legal program at the U.S. Committee for Refugees and Immigrants in Arlington, Va., who worked with children at Lackland.

In the San Antonio and Corpus Christi area alone, about 1,100 unaccompanied youths are being held in smaller shelters, advocates said.

The number of youths caught by the Border Patrol in the Rio Grande Valley, epicenter of the crisis, fell from 1,985 at the end of June to 672 in late July — a 66% drop.

It’s not clear whether the number could increase again in coming weeks. Police in Mexico and Central America appear to have cracked down on those attempting to travel north illegally, advocates said, creating bottlenecks they say could still burst if those youths persist in crossing.

“They’re going to continue to flee,” said Jonathan Ryan, executive director of RAICES, a San Antonio nonprofit legacy advocacy group that has screened 1,600 children at Lackland. “Based on past trends and the fact that conditions have not improved in home countries, we’re going to see another number of children coming next year.”

molly.hennessy-fiske@latimes.com

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