Did Overdevelopment Make Flooding in Houston Worse?

As residents recover from Harvey, some experts wonder if the disastrous flooding could have been mitigated.

After six days of rainfall, parts of southeast Texas finally saw the sun on Wednesday, but Tropical Storm Harvey isn’t done yet. The storm made its second landfall in southwest Louisiana and is expected to move through the lower Mississippi Valley and into the Ohio Valley in the coming days.

At least 21 people have already lost their lives due to flooding in Texas, where river levels will likely remain high through the weekend. Thousands were rescued by first responders and private citizens, who took to the flooded streets of Houston and surrounding Harris County in fishing boats to help bring their neighbors to safety, and thousands more remained displaced as floodwaters began to recede.

Hurricane Harvey settles over the Gulf Coast on Tuesday, as photographed by astronaut Randy Bresnik from the International Space Station. Image credit: Flickr/NASA Goddard Space Flight Center

Despite the drier conditions, Houston’s focus “will continue to be on rescue” rather than damage assessment or recovery, Mayor Sylvester Turner said at a news conference on Tuesday, as reported by the New York Times. Jeffrey Lindner, a meteorologist for the Harris County Flood Control District, told the Times that 25 to 30 percent of the county’s 1,800 square miles of land was flooded.

Houston and Harris County are no stranger to flooding. Tropical Storm Allison inundated the area with 80 percent of its annual rainfall in 2001, killing 22 people, leaving 30,000 stranded in shelters and causing $5 billion in property damage. But as residents recover from Harvey, some experts wondered if the disastrous flooding could have been mitigated.  

Unchecked development and flood mitigation

As the ongoing trend of migration to cities played out in America’s second most populous state, urban hubs like Houston saw their populations skyrocket. The city welcomed nearly 600,000 new residents between 1990 and 2013, causing a surge in housing demand. The region’s flat landscape and relative lack of regulatory hurdles -- Houston is the largest U.S. city without zoning laws -- allowed development to continue more or less unchecked.

The Houston metro area grew to more than 1,600 square miles, and much of its natural wetlands were drained to make way for parking lots and subdivisions. During those two decades of booming population, Harris County saw nearly 16,000 acres of wetlands paved over. The White Oak Bayou watershed, which includes much of northwest Houston, lost more than 70 percent of its wetlands between 1992 and 2010, according to research from Texas A&M University.

Texas National Guard members lift residents and pets to safety after severe flooding in Cypress Creek, Texas. Image credit: Flickr/The National Guard

So, what does this have to do with Harvey? It’s widely accepted science that wetlands are able to soak up massive amounts of flood water. The wetlands loss documented in the Texas A&M study is equivalent to nearly 4 billion gallons in lost stormwater detention, worth an estimated $600 million.

The loss of natural prairies, which are highly permeable and act as sponges for stormwater, also decreased the region’s ability to handle flooding. Due to this combination of factors, in many ways Houston was a “catastrophe waiting to happen,” Robert Bullard, a professor at Texas Southern University who is known as the “father of environmental justice,” told Democracy Now.

Even if the bulk of these wetlands and prairies were preserved, it would not have been enough to prevent flooding in Harris County. Harvey unleashed an estimated 9 trillion gallons of stormwater in a 36-hour period, and the grand total may top a staggering 21 trillion gallons. But given the widespread nature of the flooding and the unique dangers it poses, it’s worth considering if new development tactics could be employed to mitigate future storms.

In addition to homes and businesses, oil and chemical plants across the region were gravely affected by the storm, further unsettling residents. Companies like Shell, Exxon and Chevron informed regulators that flooding at their plants caused the release of toxic chemicals and volatile organic compounds like toluene and benzene, prompting new questions about building standards at such facilities.

Locals became increasingly concerned after news broke of two explosions at a chemical plant in Crosby, Texas, mere hours after the operating company’s CEO evacuated employees and warned that such an event may be unavoidable. Some watchdogs also feared dangers at two nuclear reactors in East Texas and advised operators to begin a cold shutdown.

Planning for disaster

To pave over wetlands, developers must obtain permits under the Clean Water Act that require documentation of mitigation activity. This includes establishing a new wetland in the region, financing a conservation project or conducting an environmental assessment to lessen impact. But studies show this is not a given in Houston.

In 2015, Texas A&M and nonprofit research group HARC analyzed permits granted in the Houston area between 1990 and 2012. “They found that in fewer than half of the cases had the developers submitted complete paperwork, and in two thirds of the cases, there was no documentation that any type of mitigation had happened,” reported Ana Campoy and David Yanofsky of Quartz.

The Louisiana National Guard prepares a rescue mission after Harvey made landfall in southwest Louisiana on Wednesday. Image credit: Flickr/The National Guard

Through his Waters of the United States Rule, former President Barack Obama looked to extend protections to a greater number of American wetlands and require that developers pay for the construction of new wetlands in order to obtain permits. The Donald Trump administration moved to rescind the rule in February, and the story is still unfolding.

A regulatory puzzle

Widespread development is not the only planning mishap affecting Houston and its residents in the wake of Harvey. Stunningly, only 15 percent of homeowners in Harris County have flood insurance. While rules from the Federal Emergency Management Agency (FEMA) require homeowners in high-risk areas to carry flood policies, risk designations are based on outdated data, as news outlets including Quartz and the Houston Chronicle pointed out.

Homeowners without flood insurance will be forced to apply for FEMA grants, which top out at $33,000 and often take years to process. In the wake of natural disasters, most home flood insurance policies are backed by the National Flood Insurance Program, which is set to expire at the end of September, inflaming a new debate about its funding.

Other hot-button regulatory issues also come into play, mainly the revocation of another Obama-era rule that may force federal agencies to shun science while rebuilding after the storm.

A mere two weeks before Harvey struck, the Trump administration rescinded the Federal Flood Protection Standard—which would have required federally-funded infrastructure, like public housing, hospitals, fire stations and highways, to be built to better withstand flooding and sea-level rise based on scientific projections.

“If left in place, the standard would have helped reduce the loss of these services—protecting lives, lowering disaster costs and saving taxpayer dollars,” Joel Scata, an attorney with the Natural Resources Defense Council (NRDC), wrote in a blog post. “However, President Trump has continued to demonstrate his capacity for myopic leadership by committing America to paying billions of dollars in future damages, making the nation more vulnerable.”

A libertarian flood policy expert who was critical of many Obama policies called Trump’s decision “an enormous mistake that is disastrous for taxpayers,” saying the standard “would have saved billions” over time.

In the case of Harvey, the absence of such a rule means that federal agencies will fund the reconstruction of structures and roadways to the same specifications -- rather than building them to a higher standard so they can better withstand flooding.

“What’s likely to happen is we’re going to spend tens of billions of dollars rebuilding Houston exactly like it is now, and then wait for the next one,” Rob Moore, a senior policy analyst on water issues for the NRDC, told Quartz.

The bottom line

Many pundits have criticized assessments about Houston’s development and America’s federal flood protections as insensitive to disaster victims and a thinly-veiled attempt to use the storm to push a political agenda. But trying times offer an opportunity for us to take a step back, think critically about how we’ve done things in the past and determine and better path forward.

As Boullard told Democracy Now: “This storm, this flooding of this city, tells us that there is no place that is immune from devastation. … We have to change the way we do business and the way that we as humans interact with our environment.”

 

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