Many big cities in America are so-called sanctuary cities that have policies to protect undocumented immigrants from deportation and allow them to participate in everyday life. Houston, the nation's fourth-largest city and home to the country's third-largest undocumented immigrant population, isn't one of them.

But last week, when Hurricane Harvey caused devastating flooding that left hundreds of thousands of Houstonians in need of rescue and shelter, Mayor Sylvester Turner sounded very much like the leader of a sanctuary city.

“I don’t care who you are, I don’t care what your status is. I do not want you to run the risk of losing your life [in the hurricane],” he said at a press conference last Monday. “If someone comes and they require help and then for some reason [someone] tries to deport them, I will represent them myself,” said the mayor, who is also an attorney.

The dire circumstances also spurred federal immigration agents to halt their normal activities. The U.S. Immigration and Customs Enforcement (ICE) and U.S. Border Patrol assured the public that they would not conduct “routine non-criminal immigration enforcement operations” at evacuation sites, shelters or food banks. Since the storm hit, there have been no reports of federal immigration agents detaining anyone, says Kate Vickery, executive director of the Houston Immigration Legal Services Collaborative.

This all was undoubtedly welcome news to the 600,000 undocumented immigrants who live in Houston. While the city has never provided them sanctuary, it appears to be living up to its self-assigned moniker as a "welcoming city."

But statements of goodwill haven't fixed everything: Many undocumented residents remain fearful of interacting with local authorities to seek flood relief, and they wonder when the immigration enforcement leniency will end. As the city faces the daunting task of rebuilding after the disaster, it may struggle to reach out effectively to its undocumented population -- especially in the wake of the official termination of the DACA program for young immigrants. Compounding the issue is the fact that undocumented people will likely need additional assitance, given that they won’t qualify for any federal aid.

(With Hurricane Irma making its way toward Florida's Miami-Dade County, which also cooperates with ICE, these same issues are likely to arise there.)

Officials in Houston have always cooperated fully with ICE in jails, according to Vickery. Since President Donald Trump’s election, federal agents have arrested 6,200 undocumented immigrants in Houston, the largest number in the country behind only Dallas and Atlanta. For years, Harris County, where Houston is located, was one of the last large urban counties still participating in 287(g), a government program that deputized certain police officers to act as federal immigration agents in local jails. From the time 287(g) started in 2008, Harris County deported more people than any other area in the country. That program ended this past February -- but detentions out of Houston and Harris County have held steady anyway.

And last Friday, a longstanding Houston Police Department (HPD) policy preventing officers from asking about immigration status was officially rescinded to comply with SB 4, Texas' controversial anti-sanctuary cities law. A federal district judge last week temporarily blocked a majority of the law but left intact a portion requiring localities to allow officers to inquire about suspects' immigration status. Now, even in the midst of flooding and relief efforts, any Houston police officer can ask about status during regular field operations.

The policy change has not yet been announced publicly because of the department’s preoccupation with Harvey recovery, says Rafael Pantoja, a spokesperson for HPD. To ensure no one is being racially profiled, Pantoja says the policy will require officers to write up detailed reports about why they asked the question. In addition, no one can be arrested by HPD based on information about status -- all officers can do is hand off the information to ICE.

“We don’t care about status if you’re a victim or a witness [to a crime]. We have to stress that to the public,” says Pantoja.

Houston has never had policies in place meant to shield immigrants from federal authorities. But HPD is not directly responsible for the majority of detentions and deportations in the metropolitan area, says Vickery, because most are processed through the Harris County Jail, which the city does not control.

“Because the county has taken charge of [immigration issues], the city and police department don’t feel like they have a huge role to play. They kind of think, ‘talk to the county,’” Vickery says.

Both Pantoja and Vickery say that Houston officials have succeeded in building bridges with its immigrant communities even while the department fully cooperates with ICE. But under increasing pressure from federal and state forces that are hostile to undocumented immigrants, the bridge is beginning to crumble.

According to HPD data, the number of Spanish speakers reporting sexual assault dropped 43 percent in the first three months of this year compared to last, likely as a result of Trump’s victory and hardline immigration stance. Last week, even as flooding reached deadly levels, some immigrants refused to call for help for fear of being deported, despite all assurances to the contrary.

Vickery stresses that while some immigrants may feel comfortable calling Houston a “welcoming city,” many others would take issue with the term.

“Many undocumented folks would take issue with a blanket statement implying Houston is doing all it can [for immigrants],” she says. “There’s so much more that we could do. Houston has not set itself up as a strong leader in this space.”