The heavy storm that hit Alexandria in July 2019, filling the streets with rainwater and flooding dozens of basements, was considered a “50-year” weather event — the kind of deluge with a 1-in-50 chance of pummeling the riverfront Northern Virginia city every year.

But then it happened again, a little more than 12 months later. And again. And again.

Now, as Alexandria officials ask for patience while they work on updating decades-old storm water infrastructure, many residents say they are tired of waiting as they endure yet another season of torrential rain — including this week, when the remains of Hurricane Ida drenched the Washington region.

“It’s extremely stressful. You’re always living in fear of the next flood, and we don’t know if they’re going to be able to stop it at all,” said Rose Esber, who lives in a four-story condominium building near the King Street Metro station.

Her building has seen so many repeated deluges in its basement parking garage, she said, that it was dropped by its insurance company.

Concerns from residents such as Esber have grown louder and more widespread in some parts of Alexandria in the past two years, illustrating how a mix of intensifying climate change and neglected infrastructure has created a challenge that may take years to resolve — but for which a solution cannot come fast enough.

“When both of those things come together, as they have over the past couple of years, it highlights that we’re now in a crisis situation,” said Yon Lambert, Alexandria’s director of transportation and environmental services. “We’ve all been struggling with the inability to make investments in our infrastructure.”

The issue is not unique to Alexandria. More frequent, more intense storms in the Mid-Atlantic are bringing heavier rainfall to storm systems that were never outfitted for weather this severe. Years of stalled funding and maintenance, meanwhile, means those drains and pipes have not been updated for decades.

And across the region, residents, government officials and scientists alike fear it’s only bound to get worse: They worry about rising sea levels in the Hampton Roads region, flash flooding on the streets of Ellicott City, Md., or backed-up storm drains in northern Virginia, where those concerns have left at least one family keeping an emergency raft by their door.

Lambert acknowledged that Alexandria had in recent decades not put enough money behind storm sewer maintenance, particularly when it comes to updating and enlarging pipes to meet newer design standards. Current rules say that pipes and drains must be designed to withstand a 10-year rain event — taking in up to 2.7 inches of rain in one hour, or 5.3 inches over the course of 24 hours, according to the city’s definition.

“We knew it was an issue we had, and we were working on those improvements,” he said. But “the flooding was just something — it’s not like we had ever seen it before … It’s one thing to have that happen once every 20 years. It’s another thing to have it happen three times in less than two years.”

Lambert said the city has dramatically scaled up its investments in recent years, with the city council in 2018 approving a storm water utility fee and more recently dedicating $5.8 million in federal funds from the American Rescue Plan Act.

Where the city in 2012 had devoted about $28.5 million for storm water improvements over a 10-year period, it is now projected to spend nearly half a billion dollars on a wider range of projects within the same time frame, he added.

Yet Katie Waynick, vice chair of the city’s ad hoc flooding advisory group, said that compared to the scope of the problem, even more money may be needed. She has called on city council to use its second tranche of Rescue Plan money to pay for design and planning studies.

As rainfall threatens to grow even worse, Waynick also said Alexandria must do more than simply getting the system in line with existing city standards. Many of Alexandria’s 185 miles of storm sewer pipes were constructed before those standards were introduced, so ongoing capacity efforts have focused on bringing those up to the mark. But with storms 30 times more intense, that may not be enough, Waynick said.

“It’s not only about increasing the better design standard for which they’re dealing with storm water,” she said, “but also questioning the baseline definition of what ‘better’ means.”

Geography is not necessarily working in Alexandria’s favor. One-fifth of the city, which grew on the banks of the Potomac in the 1700s as a port for trading tobacco and enslaved people, is mapped as flood plain.

Some of that includes the city’s Old Town, which uses a combined storm surge and sewer system that is the focus of a separate capacity effort launching this fall. But immediately to the west, the neighborhoods of Del Ray and Rosemont rely on the city’s independent storm water system — jump-outs, storm drains and pipes — that has borne the brunt of recent flooding.

William Skrabak, the deputy director for infrastructure and environmental quality in Alexandria Transportation and Environmental Services, said that development practices from 60 to 100 years ago in those neighborhoods have also accentuated the issue.

Where current construction patterns might preserve suburban streams and leave green space around them, “a lot of those smaller streams ended up being put into pipes buried under a road somewhere,” he said. “So there’s no flood plain for the water to go.”

Instead, the water rushes into pipes. It fills the system and then backs up. It ends up on streets and alleys. And eventually it reaches residential basements — a phenomenon that John Craig, a 66-year-old engineer, said he has now witnessed at least 15 times.

Perennial deluges into the basement of his three-bedroom townhouse have caused at least a thousand dollars’ worth of damage, he said, and destroyed priceless items, including family photos and letters from his grandparents.

Out of 90 problem areas identified by the city in a 2016 modeling study, his block is not one of the 11 that has already been set to receive committed capital improvement funds from the city.

“We feel betrayed,” he said. “It is getting worse, and the city is simply saying: ‘Well, we’re really sorry about that. But there’s not enough damage from the floods to warrant the investment to fix the problem.’ ”

Lambert said the city chose to prioritize 11 problem sites to mitigate flooding for the most people, the most significant property damage and greatest overall benefit to the system.

If storm water infrastructure has always suffered from problems, researchers who study flooding say the effects of climate change are proving the need to update decades-old pipes — in a way that has become impossible to ignore.

“All infrastructure is designed to have some level of risk,” said Jonathan L. Goodall, a water resources engineer at the University of Virginia. “We’re just taking on more risk unless the existing infrastructure can somehow be retrofitted, which is expensive to do.”

A report on climate change impacts in Virginia, which he helped prepare for state lawmakers, noted that an increase in greenhouse gases — and the additional energy they trap — has resulted in more frequent storms with greater rainfall across the commonwealth.

Between 1980 and 2020, Virginia was affected by 17 tropical cyclones and 30 severe storms, according to the report. Just one extreme weather event can create enough rainfall to overwhelm the system.

“That’s that much more volume of water going through the pipes,” he said. “It’s not going to be able to take it, and you’ll have water building up in the streets.”

While some researchers, including Goodall himself, are working on real-time control mechanisms that can use computer technology and valves to optimize water storage, few other options remain for local governments looking to manage the issue, he said.

One route is the principal approach Alexandria is taking: to install bigger pipes, identify and clear “choke points,” or adding more inlets. Other flood-prone cities, such as Charlotte, have bought up homes located near creeks and rivers and replaced the houses with absorbent grasslands.

Skrabak said the city is also looking to improve more localized rain gauge measurements — Alexandria largely relies on data taken at Reagan National Airport, which is a few miles outside the city limits in Arlington — and using that data to communicate with residents more directly.

Craig and some other vocal critics of the city’s response point in part to a recent surge in residential development construction, which they claim will increase the amount of impervious surface and further exacerbate the problem.

City officials say that development codes — and the fact that residents are all concentrated in a few buildings, rather than in separate houses — mean that they will not add to impervious surface in the city. New developments covering more than 2,500 square feet, for instance, must meet the 10-year design standard and have a net zero effect on storm water.

But Waynick says those standards could be improved, too.