Is Houston’s Limited Zoning To Blame For Harvey Flooding?

Fresh on the heels of the worst rainfall event in the history of a major metropolitan area, proponents of command-and-control zoning laws are attempting to capitalize on Hurricane Harvey-related flooding to make their case.

Very simply, they’re wrong.

Refusing to let a crisis go to waste, publications like The Atlantic, Slate, The Washington Post, and others wasted little time arguing simultaneously that Houston’s lack of a traditional zoning system contributed to the disaster and that foisting new regulations on the citizens and developers is key to mitigating the next.

 

In addition to spurious theories that Harvey’s intensity was exacerbated by anthropogenic climate change (for which there exists a gaping hole in the evidence), many of these commentators’ claims relate to measures like zoning, impervious surface restrictions, and other land use regulations.

Steve Russell of Newsweek observes that, “Houston is a great location because of its access to international shipping in the Gulf of Mexico. It is not a great location for building, though, because of all its impervious cover.”

“Impervious cover” refers to basically any structure (earthen or otherwise) that channels water away rather than letting it infiltrate the ground where it fell, and is a primary culprit according to Russell. He continues, “If water could easily sink into the ground, there would be less of it ripping down Houston’s … streets.”

It’s true that impervious cover contributes to runoff and limits infiltration, but as Scott Beyer, founder of the Market Urbanism Report writes, “[It] can take only so much blame. The wetlands that have been lost to development since 1990 would have absorbed an estimated 4 billion gallons; the rainfall that Harvey dumped onto the Houston area was an estimated 20 trillion gallons.” If these figures are correct, that represents 0.02 percent of the total.

Missing from many of these analyses is that: (1) not only does Houston already have many regulations, including parking minimums (which often increase impervious cover), setback requirements and minimum lot sizes; but (2) most of the growth in the Houston area is outside of the city proper. Of 850,000 new housing units added since 2010, only 200,000 of these have been built inside Houston city limits, with much of the rest going to suburbs with zoning codes like Katy and Sugar Land.

Economic historian and Houston native, Phil Magnus, points out that Houston’s unique topography and soil make the problem of stormwater control incredibly difficult. The city and surrounding areas sit on abnormally flat land, and according to a U.S. geological survey, the clay-based soil is some of the least penetrable in the nation.

The claim that Houston doesn’t have enough “green” absorbent surface doesn’t stand up to scrutiny, either. Research provided by Vanessa Brown Calder, urban policy analyst at the Cato Institute, shows that not only does 90% of Houston’s impervious cover fall under “low level” classification, but that when compared to similarly sized American cities, Houston has substantially less impervious surface coverage.

Source: USDA Forest Service, 2012

On the topic of new development exacerbating Houston’s flooding problem, 18-year head of the Harris County Flood Control District, Mike Talbott in an interview last year said, “The mitigation that’s being done by new development is absolutely effective. They’re building stormwater detention, they’re building new channels, and all of it is being mitigated appropriately. When somebody wants to claim that, ‘well, it’s because we’re paving over all the wetlands and these magic sponges out in the prairie would have absorbed all that water,’ is absurd.”

Houston Mayor Sylvester Turner, a former Democrat state legislator, agreed:

 

Coincidentally, of about 250,000 Katrina evacuees, somewhere around 25,000 and 40,000 took up residence in Houston permanently, in no small part because of economic opportunities, but also affordable housing that was able to meet needs more quickly and cheaply precisely because of limited zoning. Indeed, Houston’s supply of apartment vacancies, at 6.8% last year is over double that of Manhattan, and well above the national average, giving Houstonians affected by Harvey the options they sorely need today. In fact, plenty of academic literature exists illustrating how regulations, including zoning, increase the cost of housing.

Despite the lack of evidence that zoning laws or more land-use regulation would have mitigated Harvey flooding, Jim Blackburn, co-director of Rice University’s research center on severe storm prediction and disaster evacuation believes that there are still measures that can be taken to lessen future flooding. Some of his ideas include bolstering reservoirs, buying and preserving wetlands, and incentivizing farmers to harvest their lands instead of selling to developers.

Blackburn sees a need to move the conversation more toward a discussion of where Americans should be living.

“What I see in front of us is a much more serious challenge than [zoning]. And it really does change some fundamental concepts about how we develop areas, where we develop areas. These are conversations no one is prepared to have in the United States,” Blackburn says.

Unfortunately, from a policy perspective, the most relevant time to discuss government’s role in disaster preparedness and recovery is sometime after the event. “Politicizing” a tragedy is also the last thing most people have a tolerance for, given the suffering, emotional, and financial costs. However, discussions of these natural disasters raise important questions about how much the public is exposed and why.

Florida is the gold standard for what’s known in economics as moral hazard, or a lack of incentive to guard against risk where one is protected from its consequences. In the years prior to World War 2, Florida was the least populated state in the south, not coincidentally, because it’s a low-lying peninsula and the most hurricane-prone region in the world. Today it’s the third largest state.

What happened in the intervening years was a distortion of risk pricing as the federal government began providing loss subsidies in the form of the National Flood Insurance Program in 1969. While aimed at encouraging localities to invest in flood prevention infrastructure, the actual outcome was to incentivize building in dangerous areas. Fully one-third of NFIP policies are based in Florida.

As the private flood insurance market, largely supplanted by the federal program, grows in size, and efforts to normalize insurance rates with actual risk are realized, development will more closely follow patterns that minimize exposure to floods and other catastrophes.

Micromanaging urban planners and zoning proponents will no doubt continue to draw attention to Harvey’s impact in order to support their bad policies, and their mouthpieces will come to erroneous conclusions like, “Reducing development, then, is one of the best ways to manage urban flooding.” History demonstrates, however, that zoning has instead been used as a political weapon to insulate the well-connected from urban densification.

Instead of reducing development or falsely pointing to zoning as a solution, we should seek ways to increase development in smarter, sustainable ways. This includes local funding for flood-mitigating infrastructure, potentially buying out property in the most disaster-prone areas (see the Coastal Barrier Resource System, implemented by President Reagan in 1982), and taking a hard look at risk incentives.

As evidenced by the dramatic reduction in loss-of-life over time when natural disaster hits, innovation, advanced construction and techniques, storm prediction, and other aspects of human ingenuity will continue to address these problems in ways government should supplement, but never replace or restrain.

Take Action

JoinGive
Salvador Ayala

Sal is the Budget & Policy Analyst for Empower Texans. He has been a committed proponent of American founding principles since 2007, shortly after receiving his J.D. from Chicago-Kent College of Law. Before joining Empower Texans, he served as legislative director for Rep. Matt Rinaldi in the Texas house and was a delegate to the 2012 RNC. In his leisure, Sal enjoys live music, digital photography, guitar, bicycling, trivia, and documentary films.

Read All Posts