Salt Lake City Mayor Erin Mendenhall had vowed to use every tool at her disposal to halt a massive immigration detention center slated for the west side.

On Monday, she reached into her toolbox and pulled out a hammer.

The city and Salt Lake County filed a joint lawsuit against Immigration and Customs Enforcement and its parent agency, the Department of Homeland Security, in U.S. District Court in Salt Lake City. The city and the county argue that the government did not complete a public environmental review of the project, cooperate with them on it nor show reasoned decision-making.

“This kind of facility has no place in Salt Lake City, not only due to its inhumane nature but also because of our limited water supply, the increased strain on public utilities systems and the potentially drastic public health and safety impacts it would have on our residents,” Mendenhall said in a news release. “Salt Lakers are legally entitled to public review and reasoned decision-making on major actions by the federal government, and it is my responsibility as mayor to defend these rights.”

A DHS spokesperson said Tuesday that the agency was reviewing its policies and proposals as it transitioned to new leadership under former Republican U.S. Sen. Markwayne Mullin of Oklahoma.

“As Secretary Mullin said in his confirmation hearing,” the spokesperson wrote in an email. “‘I will work with the community leaders and make sure that we are delivering for the American people what the president set out. … We want to work with community leaders. We want to be good partners.’”

The lawsuit seeks to halt the conversion of a warehouse at 6020 W. 300 South into a detention center that could hold at least 7,500 people for immigration-related reasons. The federal government bought the empty warehouse for $145.4 million in mid-March.

The complaint filed by the city and county argues that the facility would have significant impacts on Utah and its residents and that the agencies did not adequately address those environmental, public health and safety impacts.

“The proposed facility is a dire threat to the very essence of our community values,” County Mayor Jenny Wilson said in the release. “It would overwhelm the infrastructure in the region, harm area businesses, and strain public safety and public health resources. The federal government did not notify nor consult with local officials, including myself.”

The lawsuit alleges, for instance, that the facility, once opened, could create millions of gallons of additional sewer flows and require the city to upgrade its wastewater system.

Holding up to 10,000 people in the center could also create health issues with an ongoing measles outbreak, the filing noted. That’s a particular concern for the county, which leads public health efforts.

The two local governments said they had only received minimal communication from the law enforcement agencies and that the county’s Health Department had not been consulted on ensuring public health inside the facility.

“Regardless of one’s views on immigration, any detention facility should be evaluated based on transparency and fiscal responsibility,” Utah immigration lawyer Vanessa Contreras said Monday. “The public deserves clear answers regarding how the facility will operate, who will oversee it, and how the rights of detainees will be protected. This detention center’s transparency cannot be an afterthought.”

Citing the lack of required environmental and public reviews of the project, the complaint urges the U.S. District Court in Utah to vacate the federal agencies’ decision to buy and convert the warehouse into a detention center and halt any efforts to build it.