[flurben]

30 years ago, building in flood plains had been an established routine for decades in Texas, and all over the United States.

Using Houston as an example, 50 to 100 years ago it was the norm to bring in fill dirt from other regions, flatten and grade a piece of land, and construct a gridded residential neighborhood with total disregard for natural drainage. Flooding was dealt with by artificially channelizing bayous and streams, which is why Houston's urban waterways look so unnatural. Many of these older neighborhoods along the gulf coast were unsustainable and are not being rebuilt after hurricanes.

Starting around 30 years ago, local, state and federal policymakers started to get a clue. Neighborhoods were more commonly build to accomodate the drainage patterns -- this is why developments from the 1990's, 2000's tend to have large retention ponds, (example: https://www.google.com/maps/@29.5517845,-95.4295706,3a,75y,2... )

while neighborhoods from the 1950's-60's do not.