These are Americans. They’re our neighbors. If not Houston, who else?
Hurricane Harvey (Source: NASA)

Hurricane Harvey (Source: NASA)

These were the words of Issa Dadoush, Houston's director of building services, twelve years ago when Katrina devastated New Orleans. Sixty thousand evacuees were welcomed into Houston and nearly three times that many ultimately made the city their new home. Harris County Judge Robert Eckels said that Katrina was probably Houston's "finest moment". It's an inspiring side story of that tragedy that looms large today.

It's no unique observation to note that we live in divisive ideological times. Every event, regardless of how tragic and random, is immediately politicized on cable news and social media. We're all guilty, to a degree, of starting with a point of view and then selecting facts to create a narrative to support it. That's human nature, and in a time when we wall ourselves off — physically in our neighborhoods and culturally in what we read and listen to — we encounter few credible counter-opinions from people we respect.

The Strong Towns narrative reflexively applied to Houston is pretty simple: Houston is too spread out, its infrastructure too expansive for its unproductive tax base to properly maintain, and thus it was woefully unprepared for Hurricane Harvey. It they hadn't built all those parking lots, filled in all those wetlands and insisted on driving everywhere, this wouldn't have been nearly as devastating.

That narrative is simple. It's also wrong.

I'm going to remind our readers that I am a licensed engineer and a certified land use planner. I don't generally find it important to note that but the coverage of Harvey is inundated with expert opinions and I'm going to explain why many of them are wrong or are being misinterpreted to fit a media narrative. I've done hydrology and drainage work as an engineer and, as a planner, administered the regulatory process of impervious coverage and managing wetlands.

Here's the media narrative.

As the country’s fourth-largest city expanded, replacing prairie with impermeable surfaces such as pavement and concrete, the land was rendered less and less capable of absorbing floodwater. Without proper adaptive measures, this made an already flood-prone place more vulnerable.
— "Houston is paying the price for public officials’ ignorance." Washington Post
A big factor could be the lack of rules that helped develop Houston into the country’s fourth-largest city — and the biggest without a formal zoning code. Experts believe the lack of regulation, building in the federally designated flood area, and paving over wetlands might’ve contributed to the storm’s severity.
— "Houston’s development boom destroyed wetlands that naturally absorbed flood water — and left thousands in Harvey’s path." NY Daily News
Houston’s sprawl into a nearly 600-square-mile metropolis has required paving over acres of wetlands and prairies that once absorbed huge amounts of storm water.
— "Why development more than climate change caused Houston's flooding,"
Though its breakneck development culture and lax regulatory environment have been lauded for giving working people affordable housing, many experts and residents say that the developers’ encroachment into the wetlands and prairies that used to serve Houston as natural sponges has inevitably exacerbated the misery that the city is suffering today.
— "A storm forces Houston, a limitless city, to consider its limits," New York Times
The feeling there was that persons who own real estate should be free to develop it as they wish. It is not a great location for building, though, because of all its impervious cover. If water could easily sink into the ground, there would be less of it ripping down Houston’s rivers that just a week ago were overcrowded streets.
— "Houston Is Drowning—In Its Freedom From Regulations," Newsweek

I would like to summarize the narrative in two parts:

Part 1: Houston was so intent on growth at any and all costs that they turned their city over to developers who filled wetlands and perpetuated sprawling development patterns. (Note: This part is true.)

Part 2: Filling of wetlands and sprawling development patterns are the reason Harvey was so devastating to Houston. (Note: This part is false.)

Many of the articles quoted above, and a lot of the expert claims, come from research by Texas A&M. I'll excerpt from this article that summarizes it most succinctly:

Largely unobstructed either by rules or by natural features such as mountains, the Houston area sprawled. Between 1992 and 2010 alone nearly 25,000 acres (about 10,000 hectares) of natural wetland infrastructure was wiped out, the Texas A&M research shows. Most of the losses were in Harris County, where almost 30% of wetlands disappeared.
Altogether, the region lost the ability to handle nearly four billion gallons (15 billion liters) of storm water. That’s equivalent to $600 million worth of flood water detention capacity, according to the university researchers’ calculations.
Houston (Source: Google Earth)

Houston (Source: Google Earth)

Let me affirm: in normal times, this would be cause for serious concern. Wetlands provide natural area for stormwater to collect and percolate. When we fill them, especially when we fail to mitigate that in some way, that water will go someplace else. When someplace else is a parking lot or other compacted or impermeable surface unable to store or percolate the water, flooding will occur. There is a cumulative effect to this so that areas that were never prone to flooding suddenly flood, often in modest rain events that were easily managed previously. Stormwater management is really expensive and often fruitless as, without up front management and planning, you don't really know what is going to happen until the rains comes.

That is how things work in normal times. Houston has experienced some recent flooding events that were certainly made worse by poor land use practices. We can argue over whether or not Houston's regulatory approach is adequate — I'd note that Houston has most of the regulations other major cities have, only they are administered differently (not as zoning, per se) and I'll add that the land use pattern of downtown Houston is good and improving while that of suburban Houston is indistinguishable from what is found in most progressive American cities — but what I've experienced there suggests that it is not much different, in terms of outcomes, to what we see in most of the rest of the country.

Harvey is not normal times. We can't look at this event the way we look at other flooding events. The devastation in Houston from Hurricane Harvey is not the result of the accumulation of many bad decisions. It was simply a huge storm.

The Texas A&M research I highlighted above suggests reckless wetland filling robbed Houston of 4 billion gallons of stormwater storage capacity. For context, the Washington Post is reporting now that Harvey dumped 19 trillion gallons on Texas—a large portion of that hitting the Houston area. That means that, had those wetlands never been filled, they could have accommodated at most .02-.1% of the water that fell in Harvey—a minuscule amount.

Anyone suggesting that more wetlands or more pervious surfaces would have done anything to mitigate what has just happened is lacking a proper sense of scale.

That Washington Post article has a great graphic and this comparision to give an idea of the magnitude:

If you piled up 20 trillion gallons of water over the District of Columbia (approximately 68 square miles), the height of the water would be 1,410 feet — or almost the height of the Empire State Building.

Anyone suggesting that more wetlands or more pervious surfaces would have done anything to mitigate what has just happened is lacking a proper sense of scale.

And that's being kind. To say that Houston is "paying the price for ignorance" and is "drowning from its own freedom from regulations" is the kind of snarky, reactionary rhetoric that's sadly become all too familiar. Wrapping that kind of ideological cheap shot in the veneer of science discredits the meaning of science. The idea that Houston, a city whose residents voted for Hillary Clinton in 2016 by the way, should — as one commenter on our Facebook feed suggested — be made an example for others is really cruel. Please stop it.

This is a terrible tragedy. Let's resist filling the narrative with our ideological dogma and instead show Houston the level of generosity and — quite frankly — lack of judgment during a time of need that Houston showed New Orleans a dozen years ago. They'll be plenty of time during the rebuilding to re-examine Houston's development practices. Progress then will benefit from empathy now.

(Top photo source: US Department of Defense)

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