At 3 a.m. on Saturday, June 26, Theresa Bonham awoke to a phone call.

"My neighbor across the street called me and asked me if I had been in the basement," says Bonham, 52, who lives in the Jefferson Chalmers neighborhood of Detroit. She assumed the neighbor had seen someone trying to break in.

"So I get up and I open the basement door, and I see a bucket float by. And I'm like, 'Oh my God'."

That night, six inches of rain fell in Detroit within three hours. The heaviest downpour hit the low-lying southeastern parts of the city where Bonham lives.

The deluge overwhelmed the city's aging stormwater management infrastructure, causing widespread residential flooding. By the morning, Bonham's basement, like many others in the neighborhood, was under three feet of water and sewage. Furniture, appliances and old family photos were ruined.

Months after the storm, the space is still gutted. "The prayer is that we can get it fixed," Bonham says. "This is unbelievable."

Detroit isn't alone — communities across the country are seeing an increase in the severity and frequency of flooding due to climate change, testing the limits of water infrastructure built for a more moderate climate. The federal infrastructure bill, recently signed by President Biden, addresses that with billions of dollars for flood prevention.

That gives cities like Detroit a small glimmer of hope their outdated pipes might soon get an upgrade.

"It's better than it was before, but it's not enough," says Palencia Mobley, the chief engineer for the city's Department of Water and Sewerage, referring to the flood prevention money included in the infrastructure bill.

Mobley, 42, was born and raised in Detroit, and has seen the frequency of flood events in the city increase just in her lifetime. The past decade has been particularly bad — heavy rainfall caused severe flooding in 2014, 2016, 2019 and 2020.

"The hundred-year storm now kind of looks like a 10-year storm, because the recurrence interval has changed," Mobley says. Research shows that, as the climate warms, precipitation is also increasing, bringing heavier storms with higher rainfall. "Your system is not designed to respond to something like that."

An Aging System pushed beyond its limit

With each new storm, the shortcomings of the city's water infrastructure — which was predominantly built in the 1930s — become more apparent. The low-lying neighborhoods near the Detroit River rely on pumps to carry stormwater away. Yet on June 26, as water surged into the city's storm drains, a power outage caused several of the pumping stations to shut down.

"You had about half of what you would typically want to operate being in service," Mobley says.

The underlying structure of Detroit's network of pipes also poses challenges. The city has a combined sewer system, with wastewater and sewage traveling through the same pipes together. When rainfall overwhelms the system, the water that overflows into basements is often contaminated with human waste — posing serious health risks to residents who are exposed to it.

The bipartisan infrastructure package contains billions of dollars to help communities affected by flooding, including $3.5 billion for FEMA's Flood Mitigation Assistance program over the next five years, which is about $500 million more annually than the program has provided in years past. It also includes $1 billion for building resilient infrastructure and $500 million for flood mapping.

Mobley knows which projects she will tackle with federal flood mitigation money — but she says, in the longer-term, it's difficult to even imagine what flood-resilient infrastructure looks like when the climate is changing so quickly.

"We don't even know what to design for now, this stuff is so far off the curve," she says.

'This is our home'

Even careful planning doesn't always prevent flooding at the intensity seen this summer.

Over the past few years, the Hope Community Church, near Theresa Bonham's house in the Jefferson Chalmers neighborhood, spent $15,000 on flood mitigation measures, like a new sump pump and valves. And yet, as the rains came in late June, the church was overwhelmed by stormwater.

"The force of the water was so huge that it just popped manhole covers off the street," says Rev. Pam Pangborn, the church's executive pastor.

The church had only resumed in-person services a week prior, after worshipping remotely since the pandemic began. With their basement level flooded, they shut their doors again.

Several months after the storm, the church is still working to eradicate mold and rebuild its lower level. It's the fourth time in the past decade the congregation has had to renovate.

"We're getting good at this," Pangborn says. "We know exactly what to do to make sure we get rid of the mold."

The congregation may have to spend even more on flood prevention in the future — money which it will have to raise. But Pangborn says there's no other choice; the church has stood for more than a century.

"This is our home, and I don't know where we would go," she says. "No, we roll up our sleeves and do the work and start again."

Jefferson Chalmers isn't the only neighborhood in Detroit that has experienced recurrent flooding. Recent research from Wayne State University, located in the city, shows that more than 40% of Detroiters have experienced household flooding — and that predominantly Black neighborhoods were found to be at a higher risk. Renters were also nearly twice as likely to be flooded as homeowners.

"Why is it that disadvantaged people in the city have to go into their basements several times a year to pump out, or pail out, sewage that has gathered in the basement from a storm?" says Carol Miller, a professor of civil and environmental engineering who led the research. "The discussion needs to turn more to the design of resilient systems."

Miller, who has studied Detroit's water infrastructure for decades, says money from the federal infrastructure bill will help the city's flood prevention efforts — as long as it's spent properly.

"I'd say it all depends on the people that are making those decisions," says Miller. "Like a lot of our issues, it gets down to getting involved and ensuring that there's good oversight."

As Detroiters wait for infrastructure funding to reach them, they're left to rebuild after this summer's flooding — and hope that heavy rains don't come again.

"It's a work in progress," Bonham says as she surveys her gutted basement. She is waiting to see if she'll need to replace her boiler, which was damaged in the flood — a $9,500 expense — and she may have to spend thousands more on a sump pump. But she plans to stay, even if the flooding continues, to maintain the house that her parents bought in 1969.

"I plan to keep it as long as I can, as their legacy," Bonham says.

This story is part of an All Things Considered series looking at the state of American infrastructure and the federal legislation addressing it.