Having lived in Houston, this isn't a measure of the flood but a measure of how terrible the infrastructure is. They have terrible flood management systems but

Having lived in Houston, this isn't a measure of the flood but a measure of how terrible the infrastructure is. They have terrible flood management systems but are "rated" to handle everything but a "100" year flood... yet Houston gets 100 year floods every year- multiple ones- and has for 40 years. It's a scam involving the ratings much like the mooody's ratings scam of the last decade IMNSHO