AILSA CHANG, HOST:
Tropical Storm Harvey has brought new attention to how flood prone Houston is. The city's incredibly flat, and its flood mitigation system has been put under immense stress since Harvey hit. Two main reservoirs in the area, the Addicks and the Barker, are at peak capacity, with officials carrying out controlled leases of water to protect the dams. To hear more about the unique flooding challenges that Houston faces, we're joined now by Sam Brody. He specializes in natural hazards mitigation at Texas A&M University at Galveston. Good morning.
SAM BRODY: Good morning. Thank you for having me.
CHANG: So Houston has rapidly grown over the last few decades. And that's been possible, in part, because of the lack of zoning in the city, right? How has that created more of a flooding problem?
BRODY: Well, when you've got rapid growth and development, along with that comes roadways, rooftops and parking lots. And all of that impervious surface makes it very difficult for the water to drain into the soil. Instead, it runs into the bayous and sometimes, as in this case, into people's homes.
CHANG: And a lot of that paving, those roads, were over prairie land with grass. I understand that was - that used as like a sponge.
BRODY: That's right. There's been a lot of growth to the western part of the city, where Katy Prairie is located. And that compromises the natural infrastructure of this very flat low-lying landscape, making it difficult for that water to absorb, be held by the prairie and the wetlands and slowly release into Galveston Bay.
CHANG: Now, I understand there was a piece published last year by the Texas Tribune and ProPublica, and it says that Houston's top two flood official - flood control officials say their biggest challenge isn't managing the growth of the city, it's retrofitting outdated infrastructure. How true is that?
BRODY: I think that's true. The storm water drainage system is in desperate need of updating, but I think that's only part of the picture. I mean, we need to retrofit our pipes, but the flood situation here is also about people and about development and where we're putting our pavement, where we're putting homes in these low-lying vulnerable areas.
I think to really get out of this flood disaster over the long term, we need to think beyond pure engineering solutions and also add other solutions that range from education and messaging all the way up to a regional scale, where we're looking at where we're putting people, pavement and structures in relation to flood vulnerability.
CHANG: All right. That's Sam Brody. He's the director of the Center for Texas Beaches and Shores with Texas A&M University at Galveston. Thank you very much for joining us.
BRODY: Thank you so much for having me.
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