don't give texas money wrote:
Experts believe the main culprit is the explosive growth of low-lying riverine and coastal development, which has had the double effect of increasing floods (by replacing prairies and other natural sponges that hold water with pavement that deflects water) while moving more property into the path of those floods. An investigation last year by ProPublica and the Texas Tribune found that the Houston area’s impervious surfaces increased by 25 percent from 1996 to 2011, as thousands of new homes were built around its bayous. Houston is renowned for its anything-goes zoning rules, but the feds have also promoted those trends by providing extremely cheap insurance in high-risk areas.
That "anything goes" urban planning (or lack thereof) goes back to the 1980's. Rogue, wildcat home builders and developers with city planners just signing off on all building permits.