Why Did Houston Flood?

Hurricane Harvey's rainfall broke continental U.S. records. Here's how cities like Houston can better prepare.

NOVA on Twitter: @novapbs
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PRODUCTION CREDITS:

Digital Producer: Ari Daniel

Production & Research Assistance: Elena Renken & Erin Dahlstrom

Editorial Review: Julia Cort, Tim De Chant, Caitlin Saks

Special Thanks: Ellen Douglas

© WGBH Educational Foundation 2017

MEDIA CREDITS:

Videography & Imagery:
Aerial Cinematography - Aaron Benzel / GO 3D NOW, LLC
Google Maps
Greenpeace / Mannie Garcia
Houston Advanced Research Center,
NASA
National Hurricane Center
National Weather Service
NYC Water
REUTERS / Johanna Strickland

Music: APM

© WGBH Educational Foundation 2017

[darcassan]

Building on a swamp at sea level probably wasn't the best idea of all time.

[ADSelf]

Because we got 52" of rain in 4 days....

[enzochiapet]

Sold home in Katy in April and left TX. It's unbelievable the development in the wetlands... and it's not slowing down.

[dingo]

because it got 50" of rain and it's not on a hill, any city would flood under those circumstances

[HIDhater]

What never gets mentioned in any discussion is the composition of local soils. They are known as Vertisols which are self mulching, highly expansive clays. Bone dry, they can absorb up to 1” of water then become impermeable like concrete as the clays expand. That’s why rice is a good crop here... they hold water.

[nekomasteryoutube]

From Ontario Canada, I hope Houston survives. I wish I could help.

[CulpritTheAccused]

There were a combination of things that contributed to Houston flooding.

[Chubbycat]

Land Developer: "We don't need no stinkin' wetlands!"

[MiraDaWulf]

Reasons why:

•Massive Amounts Of Rain
•Near The Coast, Which Means The City Is Low And Easy To Flood

[u.luv.nicole]

I live in Houston and I am blessed that it didn't flood on my street

[jillhbaudhaan]

What would an updated video say about Imelda?

[leehilton]

Take a lesson from Japan. They have one hell of a flood control system in place.

[nickfatfly]

NOVA . instead of painting a hopeless picture - I propose following solutions:
A) build houses with flood prevention in mind (build in a higher ground (creating higher ground) + waterproof the basements (or no basement at all)
B) create flood dams to protect towns and roads (not a temporarily version plz)
C) dig massive candles to channel water away form city and into rivers.

[karenharris]

Okay I've been a Houston area resident most of my life--to me it's simple we got a historical storm and got over 50" of rain in 4 days!! What more needs to be said.

[mstfepj]

It's all good, people of 2101AD won't know what Florida is

[chriscampbell]

This a load of CRAP! No area can sustain 40+" of rain and not flood. Also why woould you use weather modification on your own citizens and cause billions of dollars in damages. The Houston-Galveston region has a flood control agency, they have created hundreds of retention ponds and reservoirs all over the area. They also made new businesses and subdivision to build retention ponds to offset the new developements. There are several large bayous to help carry the water to Galveston bay. I live a 1/4 mile from major bayou and thanks to 2 large retention ponds near by the bayou never overtoped. It crested 1 foot below the top. The Houston region is quite large and spread out. When the video mentions the other 2 floods they did not effect the whole region but a small area. My house did not flood and the streets remained clear. You can twist news stories to suit your agenda. If you not live in the area it is hard to understand.

[misslove]

I live here in Houston and we had a major storm some years back that was called Allison Allison had nothing on Harvey he came with a vengeance it's definitely something I would never forget it's going to be a year this month since that. Disaster hit Houston

[thomaslax]

I'd say the biggest problem is that all of our bayous converge into one. It's clear since that's the one that's still flooded over a week later as everything drains into it

[cadencerenee]

It is so sad 😣 I am Praying for all that lost there homes from to storm, or had to live everything they know behind, I hope everyone is ok. PRAY for the people of Huston Texas

[Weshopwizard]

It's flat, paved, sits on Beaumont and they got 52"+ of rain in just a couple of days.