Houston is a messy, weird, exciting, optimistic, vibrant, beautiful, big-hearted and astonishingly diverse town.

With a population topping 2.3 million, Houston is also huge and has the distinction of being the fourth most populous city in the United States as well as the largest American city unencumbered by zoning ordinances. Other cities experiencing such rapid population growth would be bursting at the seams. Houston has no seams. Even Atlanta, long the Sun Belt-ian poster child of unchecked development, has nothing on greater Houston, a flat-as-a-pancake metropolis where urban sprawl stretches on for eternity across the gulf coastal plains of Southeast Texas.

As many have been quick to theorize in the aftermath of Hurricane Harvey, Houston's anything goes approach to development has made the city — a city built atop swamps, marshes and coastal prairie — more susceptible to flooding catastrophes.

Yes, the rain-absorbing wetlands that are now peppered with highways and strip malls and cookie-cutter McMansions normally serve as the first line of natural defense against flooding. And yes, given that wetlands have been gobbled up by rampant development over the decades, Houston and its residents — who have voted down proposed zoning laws time and time again — have become increasingly vulnerable.

Disappearing wetlands

Catastrophic flooding hits Houston following Hurricane Harvey A view of downtown Houston following Hurricane Harvey, estimated to be the most expensive natural disaster in American history with damages estimated in the ballpark of $180 billion. (Photo: Win McNamee/Getty Images)

In a deep-dive into Houston's paved-over wetlands, Quartz references a study published by Texas A&M University that found 70 percent of the wetlands within the White Oak Bayou river watershed disappeared between 1992 and 2010. That same study found that throughout all of Harris County — the county where a large majority of Houston is situated and the third most populous county in the U.S. — 30 percent of wetlands have vanished during the same time frame.

At the same time, it's unfair to say that Houston would have emerged from Harvey in much better shape if there had been stricter — or any — zoning regulations in place. Zoning wouldn't have saved Houston, the so-called City With No Limits."

True — the wetlands that once flourished across Houston's New Jersey-sized metro region would have provided a buffer for floodwaters unleashed by a minor to moderate storm. But Harvey was no minor to moderate storm. Dumping 27 trillion gallons of rain across Texas and Louisiana over six days (that's enough to fill the Houston Astrodome 85,000 times), the magnitude of Harvey, which unleashed a million-year flood, is unlike anything seen before. That being said, if Houston's flood-soaking wetlands hadn't given way to ill-sited tract housing and impervious surfaces as far as the eye can see, the impact would still be dire.

Writing for Strong Towns, Charles Marohn, an engineer and land use planner, argues against the narrative that sprawl is to blame for the tragedy still unfolding along the Gulf Coast: "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."

Old maps meet rapid growth

An underwater neighborhood in Sugar Land, Texas, following Hurricane Harvey. An inundated neighborhood in Sugar Land, a prosperous 'boomburb' southwest of Houston. (Photo: Scott Olson/Getty Images)

Disappearing wetlands and a dearth of zoning aside, there are other ways in which Houston was ill-prepared for a major flood event, let alone an off-the-charts, climate change-exacerbated mega-storm like Harvey.

As the New York Times reports, flood hazard maps generated by the Federal Emergency Management Agency (FEMA) for the Houston area were "thoroughly inadequate." Described by the Times as "one of the few early warning signals that the United States has for flooding," the maps illustrate areas within the 100-year floodplain where there's a 1 percent risk of significant flooding any given year and homeowners are required to take out a policy with the National Flood Insurance Program.

In greater Houston's 100-year-floodplain, a staggering 7,000 new homes have been erected since 2010. And as the floodwaters around Houston recede, it has become glaringly obvious that homes located well beyond the 100-year floodplain — many within the 500-year floodplain, where there is a .2 percent chance of flooding in a year — experienced significant damage.

It's estimated that only 15 percent of homeowners in Harris County had federally sponsored flood insurance plans when Harvey struck. This number likely would have been greater if FEMA had updated its floodplain maps on a more frequent basis or considered relevant factors like the future impact of climate change and real estate development. Per the Times, FEMA's flood maps for Houston were so woefully outdated due to a lack of funding from Congress required to carry out the necessary research and footwork.

When disaster mitigation isn't in the budget

A floodwater-inundated street in Orange, Texas A residential street in Orange, Texas, a small Texan city abutting the Louisiana state line. (Photo: Scott Olson/Getty Images)

Here's where things get complicated.

In order to fund a controversial wall on the U.S./Mexico border, the Trump administration has floated a budget plan that makes deep cuts to federal disaster response programs including FEMA flood mapping activities, mitigation and preparedness grants for flood-prone cities and the very flood insurance that so many impacted by Harvey were lacking.

What's more, in August the White House rolled back construction standards that would have forced Houston to rebuild federally funded infrastructure projects — roads, hospitals, public housing and the like — located within flood-prone areas in a tougher, higher and more resilient manner. Per Bloomberg Businessweek, the federal government has spent $350 billion on disaster recovery over the last decade alone. Without stronger construction standards, that figure will no doubt increase.

"Streamlining" was the reason given for rescinding the Obama-era Federal Flood Risk Management Standard, which had yet to take effect and enjoyed bipartisan support, particularly among environmental groups and taxpayer watchdog organizations. The National Association of Homebuilders is one of the few groups that celebrated the rollback of the standard, which it worried would lead to increased costs for real estate developers and the construction industry.

Residents wade through a flooded street in Port Arthur, Texas Residents of Port Arthur, Texas, wade waist-high through a flooded street. (Photo: Emily Kask/AFP/Getty Images)

"This overregulated permitting process is a massive, self-inflicted wound on our country — it's disgraceful — denying our people much-needed investments in their community," said Trump in a now notorious press conference held at Trump Tower on Aug. 15, 10 days before Hurricane Harvey pounded the Gulf Coast.

However, the Washington Post reports that in the wake of Harvey, the administration is now considering instituting federal building requirements that would be strikingly similar to the ones it just banished.

Writes the Post:

This potential policy shift underscores the extent to which the reality of this week's storm has collided with Trump officials' push to upend President Barack Obama's policies and represents a striking acknowledgment by an administration skeptical of climate change that the government must factor changing weather into some of its major infrastructure policies.

With Congress now back in session, thousands of flood-impacted and flood-vulnerable homeowners in Texas, Louisiana and beyond are waiting with baited breath for the fate of numerous federal disaster prevention and relief programs designed to protect them — and the ordinary taxpayers who foot the bill following major disasters — to be decided.

'What we've done hasn't worked ...'

Man possessions from a flooded home in Houston A volunteer helps homeowners move valuable possessions to higher ground in Houston. (Photo: Joe Raedle/Getty Images)

With the future of FEMA's most crucial disaster mitigation programs hanging in the balance, one bigger-picture question remains: will Harvey change how and where Americans — specifically Texans — build homes?

As Bloomberg recently explored, changes — mostly in attitude — as big as the state itself will need to happen in Texas, which is just one of just four states along the Atlantic and Gulf coasts lacking mandatory statewide building codes. There is also no statewide program that licenses building officials.

Much like in its biggest city, which, to quote Bloomberg Businessweek, has embraced a "grow first, ask questions later" approach, red tape and pesky regulations are largely eschewed in the Lone Star State. (Decisions regarding residential buildings are left for cities to decide; most mirror the state and opt for homebuilding codes that are lax to nonexistent.)

Even Jerry Garcia, a Corpus Christi-based homebuilder who takes an "above code" approach to his own projects, doesn't think all Texas builders should be subjected to mandatory codes. "You've got to find that medium, to build affordable housing," he tells Bloomberg.

Sam Brody, a Houston resident and expert in disaster mitigation who teaches at Texas A&M University at Galveston, believes that new buildings — and even old ones — should be elevated on piles and that the city should focus on green flood-buffering techniques like wetland preservation and the creation storm detention ponds. Most of the flood-control infrastructure built in Harris County and environs to date has been "grey" in nature. That is, the paved-over metro region is armed with concrete culverts and canals that drain floodwater away but don't absorb it.

"What we've done hasn't worked," Brody tells Bloomberg. "The question is, what else can be done? Keep developing and putting people in harm's way, or do we need a shift in thinking?"

A flooded home near Sugar Land, Texas A flooded home in the fast-growing city of Sugar Land in Fort Bend County, Texas. (Photo: Scott Olson/Getty Images)

Per a sobering 2016 report published by the Texas Tribune and ProPublica, the now-retired head of the Harris County Flood Control District (HCDCD), Mike Talbott, was resistant to such shifts in thinking.

Over his 18-year tenure as executive director of the agency, Talbott was of the opinion that nilly-willy development was not heightening flood risks throughout the county and that there was no benefit to wetland preservation, a notion he called "absurd." He also rallied against considering climate change in the county's flood protection plans and referred to scientists and others pushing for wetland preservation as "anti-development."

"They have an agenda," Talbott said. "Their agenda to protect the environment overrides common sense." ProPublica notes that his successor largely shares the same views.

Not all officials are resistant to exploratory conversations about how to move forward without impeding on Texas' loose 'n' lite approach to land use and building codes.

"The discussion needs to start," Todd Hunter, an attorney and member of the Texas House of Representatives from District 32, which includes the Harvey-ravaged and residential building code-free city of Corpus Christi, tells Bloomberg. "We need to take a look at where structures are being built."

In the end, sprawl and the lax zoning regulations that birthed it aren't squarely to blame for Harvey's destruction. Only Harvey is to blame. But in warding against minor, moderate and Harvey-sized storms in the future, the City of No Limits should consider some limits — as painfully un-Texan as it is — and new ideas when rebuilding begins.

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.