Blame is counterproductive. Let’s talk solutions.
Before I begin this piece, I want to say how heartbroken I am over the devastation in East Texas. I personally lived, studied, and worked in Houston for 5 years, and have come to claim it as a home. I could not be prouder of Houstonians today, as more and more stories of courage and selflessness are being shown in daylight. This is the inspirational response we need to meet in our planning efforts.
Houston Flood Plain map
In looking at the map above, many would not recognize its shape as Houston. The map of Houston is usually drawn by the pinwheel form of its highways, but truly, Harris County is a physical representation of a tree diagram of bayous, flowing into Galveston Bay in the Southeast corner. A large percentage of the water that falls onto Houston has to make it to that Bay, in order to escape the city streets. The strategy of this is very important and should be essential to how the city is planned, built, and zoned.
Anyone who lives or knows about Houston understands that that last sentence is a joke. Houston has no land use zoning or planning efforts. However, it does have codes related to permeable surface and density, and that is that we should be talking about. Houston has always had a flooding problem but in the last large flooding event in 2016, the Tax Day floods, about a quarter of the rescues occurred outside of even the 500-year floodplain. In the last 5 years, Houston has had 3 100-year flood events, that theoretically have a 1% chance of occurring.
In the past, the Bayou’s and prairie land have done a decent job of draining the city. Most of the water goes to the bayous, with a smaller portion draining into the soil. However, the city has had unprecedented growth, and with that growth unprecedented concrete. While Houston has no zoning, it does have strict parking codes that require a high number of spaces. It also has a very poor level of permeable surface requirements, creating large runoff issues, blocking soil that already is among the slowest draining in the country. A study found that water in the Brays Bayou watershed over the last 40 years has increased 26%, while water runoff has skyrocketed 204%. This is a manageable problem and a necessary burden on new construction that must be imposed. While none of this would have prevented all of the issues with Hurricane Harvey, which dropped Houston’s entire annual rainfall on the city within a week, it would have made the problem smaller, and other flash flooding events moot.
Rainfall counts as of 8/29 vs. Avg Rainfall line
Harvey’s rainfall was both historic and predictable. With the heightening frequency of flood events and the escalation of tropical systems due to climate change, a storm like Harvey’s was inevitable. Houston has known about this, and has been preparing for flooding events for decades but has only scratched the surface of necessary improvements. The city spends $100 million annually in flood mitigation efforts and has used it in hydraulic systems, floodable highways, and water reservoirs. That may sound like a lot, but South Florida spends $664 million annually on water management and still has issues. Houston’s soil and drainage situation begs for more permeable surface and the addition of usable underground water storage tanks. There are opportunities for Public-Private partnerships to sell unpotable water directly to consumers, for large developments to create water features, and for architects to create micro-mitigation solutions to make homes and commercial buildings more valuable. Policy must also follow suit; Perhaps a cap and trade system of permeable surface? Or a series of city-funded competitions combining quality-of-life projects with mitigation efforts? Extraordinary thinking and solutions are needed to save cities all along the Gulf from predictable and frequent catastrophe.
Houston’s annual GDP is nearing $500 billion dollars and its population remains the fourth largest in the country. Its problems are not insurmountable, and ignoring them has ripple effects for each and every one of us. This week, amazing acts of courage will fill our TV screens and make us stop in awe at the incredible bravery. A DEA officer taking his small motorboat out and saving 40 people. A woman who met a stranger at a gas station and is housing 16 people in her unflooded home. And a Houstonian, known as Mattress Mack, who opened his 2 stores for victims escaping the flood, and currently has 400 people sheltered, and is providing them with food and water. There are countless stories like this of extraordinary people doing extraordinary things, and if they can do it, then I think Houston can find its way out of this in the long term as well.
PS: If you wanted to donate to help people on the ground right now, here is a list of local charities you might consider.
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Sources:
https://www.vox.com/science-and-health/2017/8/30/16214212/harvey-extreme-weather-science
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