Boomtown, Flood Town

Climate change will bring more frequent and fierce rainstorms to cities like Houston. But unchecked development remains a priority in the famously un-zoned city, creating short-term economic gains for some while increasing flood risks for everyone.

This is part of a series on Houston's flood risk. Read about why Texas isn't ready for the next big hurricane.

HOUSTON — For the third time in eight years, water gushed into Virginia Hammond’s northwest Houston home.

It was 2 a.m. on April 18. Over the next several hours, her two granddaughters — ages 12 and 15 — perched on tables, scared to put their feet in the dark gray floodwater rising below them. It nearly topped 3 feet.

“They couldn’t get in the beds because the beds were wet. They couldn’t go to the bathroom because the water was over the toilet bowl,” Hammond recalled.

“We were in there, well, trapped.”

The storm that pummeled Hammond’s modest brick home — nicknamed the “Tax Day” flood because it fell on the deadline to file federal income taxes — came just 11 months after another, on Memorial Day 2015, that also crippled the city. Together, the floods killed 16 people, inflicted well over $1 billion in damage and provoked an unprecedented uproar from Houstonians, some of whom are now suing the city over chronic flooding problems. A month after the Tax Day flood, another mega-storm hit the city, dumping well over a foot of rain on parts of Harris County, home to Houston, in 24 hours.

The area’s history is punctuated by such major back-to-back storms, but many residents say they are becoming more frequent and severe, and scientists agree.

“More people die here than anywhere else from floods,” said Sam Brody, a Texas A&M University at Galveston researcher who specializes in natural hazards mitigation. “More property per capita is lost here. And the problem’s getting worse.”

Why?

Scientists, other experts and federal officials say Houston's explosive growth is largely to blame. As millions have flocked to the metropolitan area in recent decades, local officials have largely snubbed stricter building regulations, allowing developers to pave over crucial acres of prairie land that once absorbed huge amounts of rainwater. That has led to an excess of floodwater during storms that chokes the city’s vast bayou network, drainage systems and two huge federally owned reservoirs, endangering many nearby homes — including Virginia Hammond’s.

On top of that, scientists say climate change is causing torrential rainfall to happen more often, meaning storms that used to be considered “once-in-a-lifetime” events are happening with greater frequency. Rare storms that have only a miniscule chance of occurring in any given year have repeatedly battered the city in the past 15 years. And a significant portion of buildings that flooded in the same time frame were not located in the “100-year” floodplain — the area considered to have a 1 percent chance of flooding in any given year — catching residents who are not required to carry flood insurance off guard.

Scientists say the Harris County Flood Control District, which manages thousands of miles of floodwater-evacuating bayous and helps enforce development rules, should focus more on preserving green space and managing growth. The City of Houston, too. And they say everyone should plan for more torrential rainfall because of the changing climate. (A host of cities in the U.S. and around the world are doing so.)

But county and city officials responsible for addressing flooding largely reject these arguments. Houston’s two top flood control officials say their biggest challenge is not managing rapid growth but retrofitting outdated infrastructure. Current standards that govern how and where developers and residents can build are mostly sufficient, they say. And all the recent monster storms are freak occurrences — not harbingers of global warming or a sign of things to come.

The longtime head of the flood control district flat-out disagrees with scientific evidence that shows development is making flooding worse. Engineering projects can reverse the effects of land development and are doing so, Mike Talbott said in an interview with The Texas Tribune and ProPublica in late August before his retirement after 18 years heading the powerful agency. (His successor shares his views.)

 

 

The claim that “these magic sponges out in the prairie would have absorbed all that water is absurd,” Talbott said.

He also said the flood control district has no plans to study climate change or its impacts on Harris County, the third-most-populous county in the United States.

Of the astonishing frequency of huge floods the city has been getting, he said, “I don't think it's the new normal.” He also criticized scientists and conservationists for being “anti-development.”

“They have an agenda ... their agenda to protect the environment overrides common sense,” he said.

But Talbott acknowledged that projects in the works wouldn’t come close to protecting against something like a Tax Day flood. Those include retrofitting old drainage, widening bayous and building more ponds to temporarily store floodwater.

learn more at propublica

Chris Alexakisenvironment