DHS Says ‘Alligator Alcatraz’ Doesn’t Need Environmental Review

The Department of Homeland Security argued in a brief filed to a federal appeals court that the temporary detention facility in the Florida Everglades dubbed Alligator Alcatraz isn’t a major federal action that warrants an environmental review.

The facility “is purely state funded and operated,” so it was properly excluded from National Environmental Policy Act requirements, the government said in a brief filed Tuesday in the US Court of Appeals for the Eleventh Circuit. Therefore, a lower court unlawfully halted construction under the statute, according to DHS.

A preliminary injunction from the US District Court for the Southern District of Florida ordered the facility to wind down operations due to the lack of environmental review conducted to study the detention center’s impacts on the Big Cypress National Preserve. Judge Kathleen Williams classified the detention center as a federal operation based on statements from DHS Secretary Kristi Noem and Florida Gov. Ron DeSantis (R) that the state may one day be reimbursed for the construction.

Environmental groups alleged DHS violated NEPA by allowing the Florida Division of Emergency Management to construct the facility in the ecologically sensitive preserve without any public input or agency review. The environmental groups said DHS’s US Immigration and Customs Enforcement didn’t offer a compelling emergency reason under NEPA to construct a facility that can hold up to 5,000 detainees in a protected ecosystem.

But the Eleventh Circuit granted DHS’s motion to stay the injunction in September while the appeal plays out, and detainees are still being held at the facility.

Government lawyers argued the district court ignored the US Supreme Court’s NEPA guidance in Seven County Infrastructure Coalition v. Eagle County, which reined in judicial review of agencies’ scoping and impact analysis.

While DHS was careful to clarify the detention facility was not a “major” federal action, which is the definition Congress wrote to trigger the environmental review statute, the brief argued NEPA deficiencies “do not justify coercive sanctions like vacatur or an injunction of agency action.”

Further, the government said it didn’t control Florida’s decisions on where the facility site was or how large operations would be. The Supreme Court also clarified federal agencies don’t have to consider the actions of other entities outside their own regulatory authority, according to DHS.

Environmental groups are represented by Earthjustice and Coffey Burlington PL. The Florida Division of Emergency Management is represented by the Florida Attorney General’s Office and Boies Schiller Flexner LLP.

The case is Friends o f the Everglades v. Noem, 11th Cir., No. 25-12873, appellants’ brief 12/16/25.