How does Hurricane Harvey compare with Hurricanes Katrina, Rita and Ike (and Tropical Storm Allison)

My parents house has suffered two separate one hundred year events, TS Claudette 1979 and TS Allison 2001,

and a single one thousand year event, Hurricane Harvey 2017.

This is too a short sample size from which to draw a definitive conclusion but ...

Houston flooding appears to be an ongoing problem that has not been sufficiently addressed. The solutions may be politically hard and economically expensive but the time is long past to start fixing the problem.

 

I didn't see it as sensationalist, but I can see how it can be seen that way. It's just an "easier" way to communicate the chance of an event at a given location. 500YR -> 0.2% of that event happening in any given year. I'm not as concern about how it's communicated, but more about if it is still accurate and relevant. Given roughly three 500 YR events in the HOU area over the past 3 years raises a very valid point of - are we completely off now?? May be time for a study of all events over the past 10-20 years to see if a re-calibration is needed.

 

Flood plane maps are definitely off. I think one of the issues is we are using very old technology to calculate the risk. There are too many factors to arbitrarily call something a 100, 500, or 1000 year flood. We simply have not been around long enough to fully understand the weather patterns.

If you tell me I have a .2% risk of my house and property getting flooded, then no, I am not going to worry about flood insurance. However if you tell me my house is 100% risk of getting flooded if a storm sits on top of house for 3 days dropping 50" of rain, then you can be certain my perspective will change.

We have the technology that can survey and simulate such events, taking in account for run off (or the lack of) and saturation.