Houston's Flood is a Design Problem
Professor Ian Bogost is a regular contributor to The Atlantic. His latest piece is about Houston's floodwaters. Bogost discusses the importance of stormwater management. The problem during floods, he says, isn't that too much water comes into a city. It's that the "pavement of civilization forces the water to get back out again." Below is an excerpt.
Houston poses both a typical and unusual situation for stormwater management. The city is enormous, stretching out over 600 square miles. It's an epitome of the urban sprawl characterized by American exurbanism, where available lance made development easy at the edges. Unlike New Orleans, Houston is well above sea level, so flooding risk from storm inundation is low. Insetad, it's rainfall that poses the biggest threat.
A series of slow-moving rivers, called bayous, provide natural drainage for the area. To account for the certainty of flooding, Houston has built drainage channels, sewers, outfalls, on- and off-road ditches, and detention ponds to hold or move water away from local areas. When they fill, the roadways provide overrun. The dramatic images from Houston that show wide, interstate freeways transformed into rivers look like the cause of the disaster, but they are also its solution, if not an ideal one. This is also why evacuating Houston, a metropolitan area of 6.5 million people, would have been a terrible idea. This is a city run by cars, and sending its residents to sit in gridlock on the thoroughfares and freeways designed to become rivers during flooding would have doomed them to death by water.