The supplemental request will seek funding for temporary and semi-permanent migrant processing facilities, additional personnel along the border, increased detention capacity and upgrades to "overtaxed" information technology systems, he told a House appropriations subcommittee.
"Given the scale of what we are facing, we will exhaust our resources before the end of this fiscal year," he said.
The request will be for less than less than $10 billion and will come as soon as this week, according to sources briefed on the proposal.
It isn't intended to create "policies to be aggressive on immigration," but rather to address the increased flows of migrants, according to a DHS official.
It will include a request for additional bed space and transportation funding for Immigration and Customs Enforcement, the official said. ICE is currently averaging around 50,000 people in custody, which is above the current detention funding levels. The official acknowledged that the request for additional beds is likely to get pushback from lawmakers.
The request is also expected to run into problems on Capitol Hill because of serious Democratic concerns over intent on immigration broadly, as well as the still-languishing disaster relief supplemental, which has imploded the last few weeks.
First test for acting homeland security secretary
McAleenan's appearance is his first congressional hearing since being thrust into the Cabinet-level post three weeks ago after a shake-up in the top ranks
at the department, including the departure of Secretary Kirstjen Nielsen.
Appropriations chairwoman Nita Lowey, D-New York, acknowledged McAleenan's challenge.
"It seems like the car is driving off the cliff with no one to take the wheel, though I guess, Mr. Secretary, you are now the driver," she said.
Democratic Rep. David Price of North Carolina, told McAleenan he was "grateful" that he was available to "steer this ship" as the head of DHS at a time of "maximum chaos and political turmoil orchestrated by a vindictive president."
Immigration has been a critical issue for the department, which has seen a steep uptick in apprehensions along the southern border over recent months. President Donald Trump, who's grown increasingly frustrated by the situation along the border, issued a memo Monday evening calling for sweeping immigration revisions which are already receiving pushback from advocates and Democrats.
Since taking over at DHS, McAleenan, who had been serving as US Customs and Border Protection commissioner, has been on a mini-media blitz, most recently appearing on CBS' "60 Minutes" on Sunday.
Lawmakers are "realizing that something different is happening with this crisis. It's not manufactured -- it's real. And we've got to sit down at a table and talk about ways to solve it," he said on the broadcast.
Last week, McAleenan told NBC's Lester Holt
that migrant family separations had resulted in the department "losing public trust" such that "from an enforcement perspective, it's not worth it," and that reinstating them is not on the table.
McAleenan told lawmakers Tuesday that the metal chain-link cells used to separate groups inside CBP's McAllen, Texas, detention facility, which came under intense scrutiny last summer, are being taken down and replaced with "partitions that are more appropriate in terms of appearance."
"We are gonna take out the chain-link," he said. The interior chain-link fencing has been called "cages" by some, a characterization DHS has disputed.
Earlier this month, CNN reported that Trump pushed to bring back family separations
and offered to pardon McAleenan
should he be jailed for violating immigration law by shutting the border to asylum seekers.
The President has denied both
McAleenan said he will ask Congress for the authority to keep families in custody while they move through the immigration process.
"But in terms of your broader point, the way that we are actually achieving results is when we are able to detain somebody in custody through the pendency of their immigration proceedings," McAleenan said in response to Republican Rep. Kay Granger of Texas. "That's what works with single adults right now, and that's an essential aspect of what we are going to ask from Congress for families -- being able to keep them together in an appropriate setting for a fair and expeditious process."
The Flores Agreement currently places a limit on how long migrant children can be held in detention. McAleenan knocked down the idea that the department intends to hold children indefinitely, saying, "The notion that we want to detain children for a long time is just not accurate."
During the hearing, lawmakers asked a series of questions about the situation along the border and department enforcement actions. Following on a line of questioning by Democratic Rep. Grace Meng of New York on Immigration and Customs Enforcement courthouse arrests, California Rep. Lucille Roybal-Allard noted that the concern is not going after criminals, but all undocumented immigrants who may not be the target.
"That's where the concern is and that's where the objection is," she said.
On Monday, Massachusetts district attorneys and public defenders filed a lawsuit to stop ICE from patrolling state courthouses.
Tuesday's hearing comes as the number of migrant families arriving at the US-Mexico border has reached record highs and total monthly apprehensions
are the highest they've been in over a decade. There were approximately 92,000 arrests of undocumented migrants for illegal entry on the southern border in March, up from 37,390 in March 2018.
Last month, McAleenan postponed a hearing with the House Appropriations Committee to visit the border in El Paso, Texas, amid the surge in migrant arrivals, which has overwhelmed US Border Patrol facilities and led to the direct release of families from custody.
"The only way to fundamentally address these flows is for Congress to act and to reinstate integrity into our immigration system. In the meantime, we need assistance and additional resources to manage the flow," McAleenan said during a news conference in El Paso.
McAleenan is pursuing three changes to the immigration system, according to a senior DHS official:
- Amending the Flores agreement, which regulates the amount of time migrant children can spend in custody.
- Pursuing moderate changes to credible fear determinations, so they better match asylum approval rates.
- Seeking the ability to in some cases repatriate unaccompanied children who aren't from Mexico or Canada.
This story has been updated.