The Federal Emergency Management Agency's (FEMA) Urban Search and Rescue Virginia Task Force Two (VA-TF2) searched Houston neighborhoods on Aug. 31 for survivors after flooding caused by Hurricane Harvey. (Photo: FEMA News Photo)
The Federal Emergency Management Agency's (FEMA) Urban Search and Rescue Virginia Task Force Two (VA-TF2) searched Houston neighborhoods on Aug. 31 for survivors after flooding caused by Hurricane Harvey. (Photo: FEMA News Photo)

A Tale of Two Hurricanes – and Two Cities' Readiness

Vastly different approaches to city planning for long-term flood control resulted in differing outcomes for two of the cities hardest hit by hurricanes Harvey and Irma. A UA professor of planning and real estate development talks about what helped, and hindered, Houston and Jacksonville.
Sept. 19, 2017
The National Oceanic and Atmospheric Administration's GOES-16 satellite captured this geocolor image of Irma at approximately 9 a.m. on Sept. 11. By the time it moved over Jacksonville, Florida, that afternoon, Irma had been downgraded to a tropical storm. (Photo: NOAA)
The National Oceanic and Atmospheric Administration's GOES-16 satellite captured this geocolor image of Irma at approximately 9 a.m. on Sept. 11. By the time it moved over Jacksonville, Florida, that afternoon, Irma had been downgraded to a tropical storm. (Photo: NOAA)
Captured by the GOES-16 satellite on Aug. 25 at 23:00 UTC, this image shows Hurricane Harvey as it reaches peak intensity of Category 4 with maximum sustained winds of 130 mph. (Photo: NOAA)
Captured by the GOES-16 satellite on Aug. 25 at 23:00 UTC, this image shows Hurricane Harvey as it reaches peak intensity of Category 4 with maximum sustained winds of 130 mph. (Photo: NOAA)
Water from Hurricane Irma's flooding continues to be pumped from a parking garage in downtown Jacksonville on Sept. 15. (Photo: FEMA/J.T. Blatty)
Water from Hurricane Irma's flooding continues to be pumped from a parking garage in downtown Jacksonville on Sept. 15. (Photo: FEMA/J.T. Blatty)
Arthur C. Nelson
Arthur C. Nelson

"It was the best of times; it was the worst of times … "

Throughout history, the beginning lines of Charles Dickens' classic novel "A Tale of Two Cities" have been used to illustrate life's major conflicts between joy and suffering, despair and hope. Those themes have played on repeat in recent weeks as natural disasters from wildfires to hurricanes and flooding have pummeled the U.S.

Two cities in particular — Houston and Jacksonville, Florida — have seen abject suffering and given rise to stories of survival in the wake of hurricanes Harvey and Irma. They also represent Dickens' major theme of conflict in a more practical way when it comes to flood control. Arthur C. Nelson, a professor of planning and real estate development in the University of Arizona's College of Architecture, Planning and Landscape Architecture, says the two cities are vastly different in their approaches to city planning.

Houston: Development and the Deluge

Hurricane Harvey made landfall near Rockport, Texas, on Friday, Aug. 25, as a Category 4 hurricane, and didn't leave until Aug. 28, when it re-entered the Gulf of Mexico and made its way to Louisiana.

"Harvey rapidly intensified very close to landfall. It was not predicted to reach Category 4 intensity so close to landfall," said Thomas Galarneau, an assistant professor in the UA's Department of Hydrology and Atmospheric Sciences. "Harvey was an extreme, high-impact event that produced damaging winds and storm surge near the coast, and then remained quasi-stationary over south Texas for three to four days and dumped feet of rain."

In some places, more than 50 inches of rain fell, wreaking havoc on the nation's fourth-largest city. In the aftermath, many wondered: Was Houston, with an average annual rainfall of 45.28 inches, equipped to deal with that much water all at once? The answer, backed by a history of fatal and expensive floods, was an unequivocal no.

From the time Houston was founded in 1830, newspapers have told the tale of a town built to flood. In recent years, a 2015 Memorial Day flood and the April 2016 "Tax Day" flood killed 16 people and caused more than $1 billion in damage. And Houston isn't alone. The National Severe Storm Center says flooding, which can occur in any of the 50 states at any time of the year, causes more damage in the U.S. than any other severe weather-related event — an average of $5 billion a year.

"Hurricanes have cost American taxpayers trillions of dollars in total economic losses," Nelson said. "The lesson of all hurricanes and monsoons is that the impact of flooding can be reduced by following key planning and design principles."

Nelson said three elements — impervious surfaces, water conveyances and water sponge landscapes — should be part of any regional or local master plan for flood control. Deficiencies in all three can have devastating consequences, as shown by Houston's continuing flooding issues.

"Because Houston is so sprawling, the square feet of impervious surfaces per person in Houston is higher than the national average by quite a margin," Nelson said, explaining that impervious surfaces include things such as parking lots, streets, driveways, home sites and sidewalks. "If you have lots of impervious land area per resident, as Houston does, the outcome will be more rainwater runoff than natural or man-made systems can handle."

Without adequate water conveyances to direct that runoff to streams, canals and flood-control areas, cities flood. And that flooding can be intensified by the overdevelopment of water sponge landscapes, such as farmland and other open areas that naturally absorb floodwaters.

Houston's rapid low-density development erased many of the naturally occurring water sponge landscapes that could have minimized the effects of flooding. If Houston had Phoenix's density, Nelson theorized, 500 square miles of water sponge landscape could have been saved, reducing the damage from flooding in the city.

Although the damage already has been done, Nelson said some steps could be taken to lessen the impact of flooding in the future, including minimizing the footprint of impervious surfaces.

"You can do things on the property, such as catchments and vegetation, that would minimize the adverse effect of having impervious surfaces," Nelson said. "But the better solution is to identify the most important water absorption landscapes and, as a matter of public health and safety and welfare, don't allow development on them. Because if you do, you're going to exacerbate future flooding.

"But how do you do that? How do you tell a property owner, 'You can't build on your land'? You can't do that in a property-rights state like Texas, or in most other states, frankly," Nelson continued. "But there's a lot of regulatory things that you can do to manage the development that does take place. That's called the police power of planning."

The solution is easier said than done, as evidenced by multiple lawsuits filed against ReBuild Houston, a 2010 plan to improve roads and old drainage systems. As Houston leaders focus on moving forward, Hurricane Harvey could end up being the impetus for change, as Hurricane Andrew was for Florida in 1995.

Jacksonville: How Planning Became Protection

In August 1992, Hurricane Andrew wrought devastation along a path through the Bahamas, Florida and Louisiana. The Category 5 hurricane, which made landfall in Miami-Dade County, Florida, caused an estimated $26.5 billion in economic damage and killed 65 people. In light of the destruction, Florida's building codes were assessed and changed.

Four hurricanes hit Florida in 2004, after which a 2005 study conducted by the University of Florida reported, "Homes built under the new Florida Building Code that became effective in 2002 sustained less damage on average than those built between 1994 and 2001."

Building codes serve to protect structures from damages inflicted by hurricane-force winds, but Florida is still vulnerable to flooding resulting from storm surges and excessive rain.

"If tropical storms are not moving fast, like Harvey, you have all of the precipitation dumping in the same area," said Xubin Zeng, director of the UA's Climate Dynamics and Hydrometeorology Center. "That is in contrast to Irma, which really moved very fast. You still have the heavy precipitation, but it's not in the same area."

By the time Irma hit Jacksonville, it had been downgraded from a hurricane to a tropical storm, albeit one that still packed a significant punch. The National Weather Service in Jacksonville reported storm surge flooding exceeded the record set in 1965 during Hurricane Dora, and on Sept. 11 a record daily maximum rainfall of 4.54 inches was set, surpassing the old record of 4.12 set in 1960.

Early estimates say 500-plus homes in Jacksonville suffered severe flood damage, a figure that could rise as storm waters from the north rush toward the Atlantic Ocean through an already-flooded St. Johns River basin.

"Part and parcel of good planning is exercising the police power to protect the public health, safety and welfare, and that may mean preventing development on these landscapes that can absorb water to help manage long-term flood control," Nelson said. "Maybe we just go ahead and buy those landscapes and turn them into a public open space, like parks."

That is exactly what Jacksonville is doing with its long-term floodplain management program. A 2010 progress report indicated the city had targeted various areas for acquisition with the intention of preserving the areas as open spaces. It also was noted that new construction would be prevented on flood-prone properties purchased by the city for the purpose of removing buildings from the special flood hazard area, thereby creating new open spaces.

"There are a lot of ways for a city to buy properties for this purpose," said Nelson, whose latest book, "Market Demand-Based Planning and Permitting," was just published by the American Bar Association. "You can issue general obligations bonds and then retire those bonds through property taxes.” 

According to a 2016 progress report, Jacksonville uses federal grants to acquire and preserve land in the floodplain as open space. Six properties were tagged for acquisition in 2016. The mission is so important that city officials included it in Jacksonville's recreation and open space planning, stating: "The city, in cooperation with the state and federal governments, shall acquire and preserve major stream valley corridors plus adjacent vital resources such as wetlands, wooded areas and conservation areas when deemed necessary for watershed protection."

"An alternative to acquiring land through bonds and federal grants is transferrable development rights (TDRs), where owners of land in 'sending areas,' such as water-absorbent landscapes, are sold to developers in 'receiving areas,' allowing them to increase density," said Nelson, lead author of "The TDR Handbook," published by Island Press.

"You need a master plan for your regional flood control," Nelson said. "Most regions have such plans but they often fail because of lax implementation. If we have regional flood control plans and then have sufficient money and other resources to implement them, then we will help mitigate future flood damage."

In some cities, flooding is inevitable. It isn't a matter of if the water will come, it is a matter of when. But when it comes to flood management through proper city planning, the tale of these two cities is far from over.