Should I avoid properties with "backs to bayou" on the description in Houston?

You need to just ask about flooding issues for the particular property. Some neighborhoods flood some don't even if there is no history of flooding there is always a risk. Plus this is houston every where floods even those properties no where near bayou's.

By all means you need to avoid properties like that. I've lived in Houston all my life and I can tell you that it is a city of contrast in terms of weather. Best way to describe it is it either rains too much or not enough.

We haven't had a period of prolonged rain and flooding in the last 3 years or so, but these conditions do exist from time to time. If your property backs up to a bayou or creek, then during those times of heavy rain and flooding you are going to be subject to flooding inside the house. If this happens then the resale value of your house is going to go way down.

Houston also is supposed to have a new flood zone map implemented after TS Allison - you should definitely see where these properties are on that map.