How accurate were the flood risk maps? (Houston, West: insurance, house)

[normaldude]

I'm wondering if the flood risk map was accurate in predicting which areas of Houston would flood, and which wouldn't.

Any feedback from locals would be appreciated. Thanks.



https://temblor.net/app/

[tewest86]

The map says what chance you have off flooding. It can't definitely say where it will or won't flood.

[Dopo]

The area East of Barker reservoir (West Houston South if I-10) i believe is completely flooded

[curbur]

Relatively spot on for Cypress south of 290

[aero100]

FEMA flood maps show the flood risk from storm surge and riverine flow (streams and rivers). This is how they do the maps all over the country and the areas in blue are a good measure of the elevated risk of those events.

What they don't account for is the somewhat Houston unique dead flat topography, susceptibility to massive rainfall, and the resulting surface flooding when the local drainage is overwhelmed for a few hours. That's why there are many neighborhoods in Houston that have flooded multiple times and yet do not fall on any FEMA flood map.

Sadly some homeowners are misled by this when buying that a home is not in a flood plain and do not by flood insurance even thogh they may be at elevated risk due to rainfall. Ironically the insurance would be the lowest rate "minimum risk" level since FEMA doesn't account for this risk (although they will after two flood claims in 10 years on an individual property).

[ptt]

Storm water starts rising in neighborhoods near Addicks and Barker dams - Houston Chronicle
The map above link is very accurate. All homes in yellow-orange are under water while in red-teal green are streets flooded.

[Birdman03]

Originally Posted by aero100

FEMA flood maps show the flood risk from storm surge and riverine flow (streams and rivers). This is how they do the maps all over the country and the areas in blue are a good measure of the elevated risk of those events.

What they don't account for is the somewhat Houston unique dead flat topography, susceptibility to massive rainfall, and the resulting surface flooding when the local drainage is overwhelmed for a few hours. That's why there are many neighborhoods in Houston that have flooded multiple times and yet do not fall on any FEMA flood map.

Sadly some homeowners are misled by this when buying that a home is not in a flood plain and do not by flood insurance even thogh they may be at elevated risk due to rainfall. Ironically the insurance would be the lowest rate "minimum risk" level since FEMA doesn't account for this risk (although they will after two flood claims in 10 years on an individual property).

Regarding this please note the following from Harris County Flood Control District (HCFCD):


Flood Insurance: Who Needs It?
EVERYONE!
The effects of flooding do not endwhen the water recedes. Flood Insurance can help you get back on your feet.


Everyone living in a participating community of the National Flood Insurance Program (NFIP) can buy floodinsurance. Harris County and the incorporated cities within the county areparticipants in the NFIP. Just because your home is not mapped within the100-year floodplain does not mean that you are free from the potential toflood. FEMA Flood Insurance Rate Maps (FIRMs) show areas subject to floodingfrom a primary flooding source, typically major rivers, bayous and theirtributaries, and are meant to help determine the risk of flooding for aproperty. However, flooding from sources that are not identified on the FIRMs is possible and occurs often in Harris County. Many homes flood because excess storm water cannot drain into a storm drainage system fast enough to prevent localized ponding from reaching the inside of a home. On a national basis, one-third of the flood loss claims are from property located outside of the mapped 1% (100-year) floodplain. This does not mean the FIRMs are wrong. It simply means that not all flooding sources are calculated when determining risk.

[Dopo]

Whatever,
just insurance companies trying to make more money

I bought where it doesn't flood, so I'm not buying flood insurance
During Harvey, I was able to drive everyday around my whole neighborhood and to the grocery store.

[WRM20]

Originally Posted by Dopo

Whatever,
just insurance companies trying to make more money

I bought where it doesn't flood, so I'm not buying flood insurance
During Harvey, I was able to drive everyday around my whole neighborhood and to the grocery store.

Insurance companies don't make any money off of flood insurance, except maybe an administrative fee for dealing with the customers. The insurance itself is provided by the government(yeah, I know there are a few private flood insurers, but they are rare).

My house didn't flood either, but I still have flood insurance, just in case something totally unexpected happens. There is nowhere in Houston that will never, ever, flood.

[Birdman03]

Originally Posted by Dopo

Whatever,
just insurance companies trying to make more money

I bought where it doesn't flood, so I'm not buying flood insurance
During Harvey, I was able to drive everyday around my whole neighborhood and to the grocery store.

That is good news. It may be helpful for you to look into why your neighborhood remained unaffected by Harvey. Local drainage conditions may change especially if there has been additional development/construction nearby.

Many other people thought they were in an area that did not flood but found out differently during Harvey. Now they are forced to either move, improve drainage/elevate, or stay and risk future flooding as the result of factors of which they may or may not be aware.