Design in a Time of Uncertainty
By Rives Taylor, Principal, Global Resilience Research Lead
HARC's Gavin Dillingham, Program Director, Clean Energy Policy, comments on the impacts and aftermath of Hurricane Harvey, with true Houstonian perspective.
When Hurricane Harvey was finished with Houston, it had dumped a record 51 inches of rain, exceeding the average total yearly rainfall by one inch.1 Overall, approximately 27 trillion gallons of water fell from Harvey after making landfall2. To those familiar with the eighth wonder of the world, the Houston Astrodome, Harvey’s rain would fill the Astrodome 86,000 times.
Current estimates for property loss across Texas are valued at $150 billion to $180 billion, about 10 percent of the total GDP of Texas3. This number does not take into account loss of economic activity and productivity, displacement of families, or injury and illnesses directly associated with the storm and its aftermath.
There is considerable discussion about what could have been done to prevent such a catastrophe. It is easy to look back after the storm and second guess previous decisions that led to the current region’s footprint. We have been asked whether any city could have prevented the flooding. I would suggest not. “Cities don’t build for such truly extraordinary flood events4 or storms that can engulf entire cities.5 Existing design standards based on historical meteorological trends are clearly in need of overhaul in light of these events".
That being said, the Houston metropolitan area did heighten its flood risk. Within the 9,000 square mile region, large portions of coastal prairie and wetlands have been paved over with impermeable surfaces. Development is allowed along the bayous and reservoirs without flood mitigation standards. The Houston region has been able to develop in this manner because 500 plus year storms have been infrequent. And with local, state and federal resources, recovery has been relatively quick. “However, within the past three years we have seen three exceptional storms that have resulted in severe flooding, straining the loss recovery capacity of FEMA, the insurance industry and the affected communities.”
A shift from business as usual will require a change in mentality from loss recovery to storm risk mitigation, and by all indications from FEMA Director Long, communities should make this shift sooner rather than later.
There is a lengthy list of things the Houston region can do to limit future risk. These include, for example, limiting development on the reservoirs, increasing building foundation heights, low impact development, on-site storm water detention and placing on-site generation above ground level. In recent years some of these standards have been put in place for new construction. However, a substantial amount of funding must be identified, and infrastructure design standards updated, to rebuild infrastructure to mitigate storm risk. Fortunately, communities can begin to look into the growing number of resilient design standards, such as the American Society of Civil Engineers “Envision” rating system, and “resilience bonds” to fund this work.
Rebuilding is already underway in Houston. As Mayor Turner stated, “we are a can-do City” and “we are not going to engage in a pity party.” As the City begins these efforts, it cannot ignore the coming storm risk due to climate change, nor can any surrounding communities. This rebuilding effort should not be done in silos. Development in one community impacts the viability and livability of other communities. Currently, there are a patchwork of jurisdictions with varying building standards and infrastructure requirements. As communities look to rebuild, it is imperative that they begin to coordinate with their neighbors to implement strategies that can enhance the adaptability and resilience of all communities.
Regional collaborative models have been developed across the country to improve adaptive capacity and resilience of communities. These collaborative efforts are not a result of mandates or regulations. We all know that “regulation” and “mandate” are “fighting words” in Texas. Rather, these are frameworks and strategies that can identify cost effective, market-driven solutions. There are a variety of local, state and national resources that have experience developing these strategies. It is in the region’s best interest to begin to reach out to these organizations to rebuild a more resilient community.