The following is derived from an interview about the 2017 disaster with Dr. Galen Newman, a Fellow in the Institute for Sustainable Communities and a member of the Hazard Reduction and Recovery Center at Texas A&M University. His research focuses primarily on urban regeneration and flood resilience.
Harvey was different. While many hurricanes pose serious flooding risks to coastal areas, the danger often lies in the rapid rise of seawater known as a storm surge. There is a reason that Harvey’s storm surge was hardly mentioned in the weeks and months following its landfall: the most serious flooding was caused by excessive rain. In an area that is accustomed to only 50 inches of precipitation annually, Harvey’s nearly 48 inches of rainfall was devastating. This inundation of water posed a completely different set of challenges for the Houston area.
Accordingly, it was nearly impossible for authorities to plan for the 2017 hurricane. The unique nature of the storm resulted in an unprecedented strain on Harris County’s stormwater infrastructure system. Due to relentless and widespread rainfall, one-quarter of the resultant flooding occurred in areas outside of the 100-year floodplain. The new and unpredictable pattern of flooding had catastrophic effects on some Houstonians. Flood insurance is not required outside of designated floodplains and as a result, many of those whose property was damaged or destroyed were forced to start over from square one.
While Harvey was a particularly devastating event, Houston was previously vulnerable to any major rain, storm, or hurricane occurrence. The relaxed regulation of land use zoning and widespread development (much of it within existing floodplains) meant that a substantial amount of land was covered by impervious surfaces like concrete and asphalt. Weep holes—the gaps within brick walls that allow for drainage and ventilation—were easily clogged. Combined with relative inattention to stormwater infrastructure, these practices led to inadequate drainage in neighborhoods all over Harris County.
Keeping it Local
Preparing for the next big storm must be undertaken by planners and policymakers at all levels of government and private enterprise. While large-scale infrastructure improvements and national or state hazard mitigation plans can be helpful, it is critical to focus on smaller scale issues that could endanger individual communities and neighborhoods. This is especially salient when addressing issues in underserved communities. For example, some lower-income neighborhoods in Houston were especially vulnerable because of their open ditch drainage system and their proximity to industrial sites that could potentially contaminate floodwaters. Local issues like this are easy to gloss over at the national level. It is critical for lawmakers and planners to address the issues and concerns of individual communities and neighborhoods while drawing up large-scale mitigation plans.
There is also much to be done at a more regional level. The Texas Department of Transportation is keeping this in mind with long-term infrastructure projects, such as a redesign of highway 45 that will integrate detention ponds and pumps to prevent highway flooding like what occurred during Harvey1. The goal is to prepare for the 100-year storm, which may be insufficient given that Harvey was a 500-year storm and these kinds of events are projected to happen more frequently in the coming years.
The storm’s aftermath forced cities all over the country to take a more critical look at their respective infrastructure and hazard mitigation plans. Cities have begun encouraging sustainable development that reduces the negative impacts on natural hydrology and drainage. Changes can also be seen in floodplain development. Building parks and other types of green infrastructure in floodplains prevents substantial losses while benefiting the local community. Buyouts in flood-prone areas becoming more common as well, as cities seek to move people and businesses from high-risk areas. While every storm is different, focusing on local issues as well as city and statewide mitigation plans puts cities in the most resilient position possible. With the negative consequences of climate change unlikely to halt anytime soon2, Houston will need to take an aggressive approach in order to lose its reputation as one of the most flood-prone cities in the United States3.
Dr. Galen D. Newman is an Associate Professor in the Department of Landscape Architecture and Urban Planning at Texas A&M University (TAMU). At TAMU, he also serves as Associate Department Head, Coordinator of the Bachelor of Science in Urban Planning Program, Associate Director of the Hazard Reduction and Recovery Center, and Discovery Lead for Community Resilience for the Institute for Sustainable Communities. His research interests include urban regeneration, land use science, spatial analytics, community flood resilience, and community/urban scaled design. His current research focuses on the integration of urban regeneration (the reuse of vacant properties in shrinking and growing cities) and urban flood resilience.
About the Author: Wayne Powell is a first year Master’s student specializing in transportation and housing/community development. He is a research assistant with the Center for Urban and Regional studies focusing on accessibility in public transit. He hopes to further his education and career in planning by studying how technology can be used to shape cities and their transportation networks.
- Delaughter, Gail. “Flood Control Is A Big Part of A Major Houston Transportation Project.” Houston Public Media, 24 Aug. 2018, http://www.houstonpublicmedia.org/articles/news/transportation/2018/08/24/301631/flood-control-is-a-big-part-of-a-major-houston-transportation-project/
- “IPCC Special Report Global Warming of 1.5ºC.” IPCC – Intergovernmental Panel on Climate Change, 6 Aug. 2018, http://www.ipcc.ch/news_and_events/ma-p48.shtml.
- Satija, Neena. “Boomtown, Flood Town.” Scientific American, Springer Nature American, 8 Dec. 2016, http://www.scientificamerican.com/article/boomtown-flood-town/.
Featured Image: Cars floating down a flooded street in Houston, Texas. Photo credit: Dominick Del Vecchio, FEMA.