Buying a Home in a 500 year Flood Plain

Questions on how we spend our money and our time - consumer goods and services, home and vehicle, leisure and recreational activities
Post Reply
harrad
Posts: 17
Joined: Mon Sep 29, 2014 6:50 am

Buying a Home in a 500 year Flood Plain

Post by harrad » Mon Oct 30, 2017 6:03 am

We have an option to buy a home in the Houston suburbs which is in a 500 year flood plain. The past few years when Houston had major flooding issues, the home or the street did not see flooding (tax-day flood, memorial-day flood and hurricane Harvey). I got this data from the previous owners and cross checked with sites showing the extent of flooding from these events.

FEMA flood plain maps show that the street in front of the home is in the 500 year flood plain and the home is 2 feet above the street surface. While we plan to get flood insurance, should we pass on this opportunity?

tampaite
Posts: 389
Joined: Wed Feb 18, 2015 9:29 pm

Re: Buying a Home in a 500 year Flood Plain

Post by tampaite » Mon Oct 30, 2017 7:18 am

harrad wrote:
Mon Oct 30, 2017 6:03 am
We have an option to buy a home in the Houston suburbs which is in a 500 year flood plain. The past few years when Houston had major flooding issues, the home or the street did not see flooding (tax-day flood, memorial-day flood and hurricane Harvey). I got this data from the previous owners and cross checked with sites showing the extent of flooding from these events.

FEMA flood plain maps show that the street in front of the home is in the 500 year flood plain and the home is 2 feet above the street surface. While we plan to get flood insurance, should we pass on this opportunity?
Yes. Flood insurance is a waste of money unless you are IN an actual flood zone.

wilshuer
Posts: 89
Joined: Tue Dec 11, 2012 10:40 pm

Re: Buying a Home in a 500 year Flood Plain

Post by wilshuer » Mon Oct 30, 2017 7:23 am

If it didn't see flooding during any of the recent events, the likelihood is probably very low. Definitely get flood insurance. Also look for the flood maps to be updated. Surprisingly they were very accurate in most places in my area, other areas I think less so.

The challenge you may run into is simply getting regular homeowners, expect to pay a hefty premium right now - considering very few of the homes that flooded have any payout from the insurance companies, they are still taking the opportunities to raise rates. Just received my renewal and saw an increase of 40%. Shopping around right now and aren't finding any that are issuing new polices at the moment.

Now, something to consider with the three flood data points from the past two years. During the tax day flood, my street saw flooding up to two feet. Neighbors who parked on the street had flooded cars, and one house at the end of the street (short cul-de-sac) had water up to his front door, did not enter but close. It drained out in less than an hour once the rain stopped, and all this over a span of 2-3 hours. During the memorial day flood and Harvey, our street never had water on it, the bayou nearby got about 1ft from the top, needing about another 6 feet to meet the same level as the tax day flood. I'm in Kingwood and had many friends less than 0.5 mi from us get 3-4 feet in their house during Harvey, and were not flooded in the two events last year. So, all that to say while you have good data points to assess risk, it's not only the amount of rain, but the rate, and what is upstream from you - reservoirs.

Whether you purchase or not is a personal decision, chances of it flooding are likely very low given success with Harvery. However be financially wise and insure against the risk. I cleaned out too many houses of people without insurance and seeing their life's positions covered in muck on their front lawn that illustrate the financial devastation it can cause. Those I helped with insurance had a very different disposition.

wilshuer
Posts: 89
Joined: Tue Dec 11, 2012 10:40 pm

Re: Buying a Home in a 500 year Flood Plain

Post by wilshuer » Mon Oct 30, 2017 7:31 am

tampaite wrote:
Mon Oct 30, 2017 7:18 am

Yes. Flood insurance is a waste of money unless you are IN an actual flood zone.
Actually, beg to differ. It's a matter of assessing risk and looking at past events, not simply blindly looking at the floodzone maps. Particularly in Houston where the pace of development has passed the map updates, there were areas that flooded outside of flood zones and people didn't have insurance. My area was fairly close between reality and FEMA maps. Other areas were quite different.

Forbes actually has this article and from a quick scan it doesn't even consider Harvey flooding https://forbes.com/sites/trevornace ... 50ce169938

User avatar
Tamarind
Posts: 641
Joined: Mon Nov 02, 2015 2:38 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Tamarind » Mon Oct 30, 2017 7:34 am

I don't have an answer for you. But here are some things you should think through before buying a particular home in an area subject to flooding.

In some areas "century plus" storms are happening much more frequently than the name would suggest. In others, the storms may not have changed much but the runoff patterns have changed dramatically as upstream and surrounding areas are developed. Flood plain maps are expensive and time consuming to make so they don't get updated very often.

How long do you plan to stay? If you intend to sell, when do you imagine yourself selling and to whom?

What flood resistant features, if any, does the house have? How tall is the foundation/basement? How much of the critical stuff (hvac, electrical conduit, water heater, etc) is lower than the first floor?

What are the surrounding surface water features? Where does runoff flow during a large storm? Does the lot direct runoff towards or away from the house?

What would you need to do if the house flooded? How about just the basement area? What would be the financial impact on you? Is there anything you can do to mitigate that?

tampaite
Posts: 389
Joined: Wed Feb 18, 2015 9:29 pm

Re: Buying a Home in a 500 year Flood Plain

Post by tampaite » Mon Oct 30, 2017 7:36 am

wilshuer wrote:
Mon Oct 30, 2017 7:31 am
Actually, beg to differ. It's a matter of assessing risk and looking at past events, not simply blindly looking at the floodzone maps. Particularly in
how do you assess risk? by looking at floodzone maps right? If you just go by ONE past event, you are miscalculating your risks.

Rupert
Posts: 2670
Joined: Fri Aug 17, 2012 12:01 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Rupert » Mon Oct 30, 2017 7:42 am

tampaite wrote:
Mon Oct 30, 2017 7:36 am
wilshuer wrote:
Mon Oct 30, 2017 7:31 am
Actually, beg to differ. It's a matter of assessing risk and looking at past events, not simply blindly looking at the floodzone maps. Particularly in
how do you assess risk? by looking at floodzone maps right? If you just go by ONE past event, you are miscalculating your risks.
Well, actually, the floodzone maps are outdated in many areas because they are based on distant events. Not sure that relying on a more recent event is any less rational than relying just on floodzone maps. You gotta look at the big picture, including whether flood insurance, which for a person living in a 500 year flood zone is relatively cheap (less than $500 for maximum FEMA coverage), is a significant expenditure for you.

tampaite
Posts: 389
Joined: Wed Feb 18, 2015 9:29 pm

Re: Buying a Home in a 500 year Flood Plain

Post by tampaite » Mon Oct 30, 2017 7:54 am

Rupert wrote:
Mon Oct 30, 2017 7:42 am
You gotta look at the big picture, including whether flood insurance, which for a person living in a 500 year flood zone is relatively cheap (less than $500 for maximum FEMA coverage), is a significant expenditure for you.
IMO, I still think that's a wrong way of looking since you will always have others who say that spending say $500(in premiums) to protect your say, $500K home(investment) is only 0.1% and it's a prudent way.

My suggestion: if you are in 500 year floodzone, it's still a waste of money. If you have the dollars, spend it but if you are looking to invest wisely, save it.

stan1
Posts: 4979
Joined: Mon Oct 08, 2007 4:35 pm

Re: Buying a Home in a 500 year Flood Plain

Post by stan1 » Mon Oct 30, 2017 7:55 am

Is this home a private sale and you have a lot of time to assess the house or is it an active listing and you need to make an offer today? That will influence what you can do. If the house is an active listing and perceived to be lower risk of flooding I'd guess it will sell very fast.

How close did the flooding in the 3 storms come to the neighborhood? How close is the neighborhood to creeks and bayous? Water comes from 3 places: flow from upstream, backup from downstream, and what comes down in the neighborhood. If it was me I'd look at every map I could find and drive around the neighborhood for a 1 mile radius looking for signs of anything that could flow or back up. I'll assume the house is not behind and below the Addicks and Barker dams. This analysis takes some time which you won't have if you need to make an offer today or tomorrow. You could also hire a civil engineer to give you an assessment. In short I'd try to get more data to understand the risk and decide whether I should buy the house.
Last edited by stan1 on Mon Oct 30, 2017 8:02 am, edited 1 time in total.

User avatar
Pajamas
Posts: 2780
Joined: Sun Jun 03, 2012 6:32 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Pajamas » Mon Oct 30, 2017 7:57 am

I think many people misunderstand what the odds are. If you are in a 500 year flood zone, you have a 1 in 500 chance of being flooded in any given year. However, you have a chance greater than 1 in 20 of being flooded over a thirty year period because of how probability works. Here is some information about that:

https://washingtonpost.com/graphics ... d-compare/

What is also clear is that the idea of a "500 year flood zone" is not really meaningful, especially in Houston, where they have been three so-called 500-year floods in just three years:

https://vox.com/science-and-health/ ... od-meaning

Also, changes in infrastructure and developed areas has occurred and the climate and weather are changing, so what has not flooded in the past may flood in the future.

I would seriously think twice about buying a house in or adjacent to a 500-year flood zone even if it were two feet above ground level. Seems like it would still be a big inconvenience and a flood could still cause problems with the foundation of the house or underground utilities. I also would not want to rely on any flood protective structures like levees because we saw what happens when they fail in the New Orleans area during Katrina.

Also consider that the flood insurance program is in financial trouble. It doesn't make sense to most people for the government to keep paying to rebuild private dwellings in flood areas or even to spend a lot of money for structures to protect them, especially when the state and local governments won't be bothered to implement basic requirements in legislation and regulation (zoning and building codes) to prevent flooding in the first place. So, I would not expect federal flood insurance to be reasonably-priced or even available in the future, in many cases.

https://vox.com/2017/8/26/16208230/ ... ood-damage

christophertowle
Posts: 18
Joined: Sun Mar 01, 2015 12:15 am

Re: Buying a Home in a 500 year Flood Plain

Post by christophertowle » Mon Oct 30, 2017 8:16 am

As a fellow Houstonian right up from Cypress Creek who thankfully did not flood, my recommend is to buy the flood insurance. It is the cheapest insurance you will ever buy. Something like $400 for $250K of coverage.

The flood plain maps are useless these days with all of the hyper-growth we have had in the last 10 years. Best comparison is Harvey, Tax Day and Memorial day events.

Keep in mind a few things about flood insurance:
It only covers the structure, it does not cover outbuildings - if you have a shed or shop it will not cover.
It does not cover cars getting flooded, that will be different claim.
It does not cover incidental living expenses if you are displaced for extended period.

I am no insurance person, but my wife is adjustor so I see the claims side of things and hear the horror stories of people that have 'never flooded' and then don't fully understand that their homeowner policy does not cover rising water, only falling water. Now they are out $100K+ out of pocket and FEMA assistance is a joke as I believe it is income based.

Best of luck.

emoore
Posts: 337
Joined: Mon Mar 04, 2013 8:16 pm

Re: Buying a Home in a 500 year Flood Plain

Post by emoore » Mon Oct 30, 2017 8:18 am

I wouldn't go near a house in any sort of flood plain but that's my opinion. I think the weather is going to change drastically because of "topics we can't discuss on this site" I think there is a decent chance that 500 year flood plains turn into a 5 year one.

Jack FFR1846
Posts: 5769
Joined: Tue Dec 31, 2013 7:05 am

Re: Buying a Home in a 500 year Flood Plain

Post by Jack FFR1846 » Mon Oct 30, 2017 8:35 am

How much more is a house 20 feet higher in elevation going to cost? I don't know Houston, so don't know.....do you have to go 10 miles away? 100 miles?
Bogle: Smart Beta is stupid

User avatar
N1CKV
Posts: 669
Joined: Wed Mar 21, 2012 8:18 am

Re: Buying a Home in a 500 year Flood Plain

Post by N1CKV » Mon Oct 30, 2017 8:38 am

I would buy the house, purchasing flood insurance would be a toss up. The best rating you can have is a "500 yr floodplain". Most that would fit in that category have either not had a flood determination or not paid attention to it because they were just told "flood insurance is not required".
https://google.com/url?sa=t&rct=j&q ... ZL4R2FTX-g

There is a huge difference in "flash floods" and flooding that can occur due to elevation. Your data set includes both, which is good. It doesn't really matter how long water sits in a structure, if it enters the damage is already done. Do not think that the house in a 500 yr flood plain is exempt from flooding from a flash flood. The reason that flash floods are so localized is because the dump of rain is extremely localized. The drain systems become overwhelmed momentarily. Flash floods can happen anywhere, the likelihood is partially based on if your canals and ditches are clear that particular day - did you vote to approve the recent property tax that pays for canals and ditch maintenance?
I have met a lot of people that claim to love money, but they also seem to be the same people that are in the biggest hurry to get rid of it.

User avatar
lthenderson
Posts: 2407
Joined: Tue Feb 21, 2012 12:43 pm
Location: Iowa

Re: Buying a Home in a 500 year Flood Plain

Post by lthenderson » Mon Oct 30, 2017 8:43 am

How high is your house from the high water mark from the last hurricane? How long do you plan on owning this property? Scientists predict that over the next 80 years that would have been 38 inches higher due to higher sea levels.

What might be a 500 year flood plain now could be a every other year flood plain in another 20 years.

student
Posts: 1333
Joined: Fri Apr 03, 2015 6:58 am

Re: Buying a Home in a 500 year Flood Plain

Post by student » Mon Oct 30, 2017 8:55 am

Pajamas wrote:
Mon Oct 30, 2017 7:57 am
I think many people misunderstand what the odds are. If you are in a 500 year flood zone, you have a 1 in 500 chance of being flooded in any given year. However, you have a chance greater than 1 in 20 of being flooded over a thirty year period because of how probability works. Here is some information about that:

https://washingtonpost.com/graphics ... d-compare/

What is also clear is that the idea of a "500 year flood zone" is not really meaningful, especially in Houston, where they have been three so-called 500-year floods in just three years:

https://vox.com/science-and-health/ ... od-meaning

Also, changes in infrastructure and developed areas has occurred and the climate and weather are changing, so what has not flooded in the past may flood in the future.

I would seriously think twice about buying a house in or adjacent to a 500-year flood zone even if it were two feet above ground level. Seems like it would still be a big inconvenience and a flood could still cause problems with the foundation of the house or underground utilities. I also would not want to rely on any flood protective structures like levees because we saw what happens when they fail in the New Orleans area during Katrina.

Also consider that the flood insurance program is in financial trouble. It doesn't make sense to most people for the government to keep paying to rebuild private dwellings in flood areas or even to spend a lot of money for structures to protect them, especially when the state and local governments won't be bothered to implement basic requirements in legislation and regulation (zoning and building codes) to prevent flooding in the first place. So, I would not expect federal flood insurance to be reasonably-priced or even available in the future, in many cases.

https://vox.com/2017/8/26/16208230/ ... ood-damage
You are correct. I think one problem is the term 500-year flood zone. It is somewhat misleading. It is better for them to just say the probability of being flooded in a given year is 1/500. I think this is how it is stated in Europe. Or better yet, state the probability of being flooded in a given 10-year period, 20-year period and 30-year period.

harrad
Posts: 17
Joined: Mon Sep 29, 2014 6:50 am

Re: Buying a Home in a 500 year Flood Plain

Post by harrad » Mon Oct 30, 2017 9:11 am

wilshuer wrote:
Mon Oct 30, 2017 7:23 am
The challenge you may run into is simply getting regular homeowners, expect to pay a hefty premium right now - considering very few of the homes that flooded have any payout from the insurance companies, they are still taking the opportunities to raise rates. Just received my renewal and saw an increase of 40%. Shopping around right now and aren't finding any that are issuing new polices at the moment.
I did get quotes from 2 insurance companies and the premiums roughly run around 100$ a month which was in the range I was expecting.
wilshuer wrote:
Mon Oct 30, 2017 7:23 am
Whether you purchase or not is a personal decision, chances of it flooding are likely very low given success with Harvery. However be financially wise and insure against the risk. I cleaned out too many houses of people without insurance and seeing their life's positions covered in muck on their front lawn that illustrate the financial devastation it can cause. Those I helped with insurance had a very different disposition.
I will no doubt purchase flood insurance. A lot of our friends had their homes flooded and seeing them go through the pain, it is a no brainier in getting one even if the odds are very low.
Tamarind wrote:
Mon Oct 30, 2017 7:34 am
How long do you plan to stay? If you intend to sell, when do you imagine yourself selling and to whom?

What flood resistant features, if any, does the house have? How tall is the foundation/basement? How much of the critical stuff (hvac, electrical conduit, water heater, etc) is lower than the first floor?

What are the surrounding surface water features? Where does runoff flow during a large storm? Does the lot direct runoff towards or away from the house?

What would you need to do if the house flooded? How about just the basement area? What would be the financial impact on you? Is there anything you can do to mitigate that?
All good questions. We plan to stay until our kids go to high school presuming that life carries on as planned(knock on wood). The house does not have a basement. I need to check the foundation height and the location of the critical equipment in the home. There is a big bayou about 0.4 miles from the subdivision and in the side of the subdivision (0.1 miles from the home), there runs a large canal which dumps into the bayou.

We can certainly pick up the pieces if the house did flood - we are fortunate that we can buy the home outright and not upset our financial plans (retirement and emergency funds untouched).
stan1 wrote:
Mon Oct 30, 2017 7:55 am
Is this home a private sale and you have a lot of time to assess the house or is it an active listing and you need to make an offer today? That will influence what you can do. If the house is an active listing and perceived to be lower risk of flooding I'd guess it will sell very fast.
The home is a private sale. I do have 7 days before the option to buy the home expires. Homes in the neighborhood sell in 30-45 days while in this particular subdivision sell in less than 3 weeks.
stan1 wrote:
Mon Oct 30, 2017 7:55 am
How close did the flooding in the 3 storms come to the neighborhood? How close is the neighborhood to creeks and bayous? Water comes from 3 places: flow from upstream, backup from downstream, and what comes down in the neighborhood. If it was me I'd look at every map I could find and drive around the neighborhood for a 1 mile radius looking for signs of anything that could flow or back up. I'll assume the house is not behind and below the Addicks and Barker dams. This analysis takes some time which you won't have if you need to make an offer today or tomorrow. You could also hire a civil engineer to give you an assessment. In short I'd try to get more data to understand the risk and decide whether I should buy the house.
The home not near the Addicks and Barker dams and his higher than the max. elevation of both dams. The home is about 0.5 miles from a major bayou which drains into the Barker dam. I need to find out more information on how much flooding was there at the street level. I did drive around the neighborhood and all homes seemed to survive the deluge without incident (from looking for and not finding signs of ripped up dry walls in the sidewalk and contractor vans around the neighborhood).
Jack FFR1846 wrote:
Mon Oct 30, 2017 8:35 am
How much more is a house 20 feet higher in elevation going to cost? I don't know Houston, so don't know.....do you have to go 10 miles away? 100 miles?
The issue is Houston being flat, I would have to drive out 10's of miles before I see some elevation.
lthenderson wrote:
Mon Oct 30, 2017 8:43 am
How high is your house from the high water mark from the last hurricane? How long do you plan on owning this property? Scientists predict that over the next 80 years that would have been 38 inches higher due to higher sea levels.

What might be a 500 year flood plain now could be a every other year flood plain in another 20 years.
I don't know the exact high water mark in the are from the last hurricane. I do believe it will get worse as new neighborhoods keep coming in the west of Houston increasing the concrete space and depriving a lot of area which could absorb the water. The home itself is about 116 feet above m.s.l - so rising seas would be not of concern. But the warming atmosphere capable of holding large volume of moisture will be an issue.

pangea33
Posts: 30
Joined: Mon Jan 16, 2017 11:57 am

Re: Buying a Home in a 500 year Flood Plain

Post by pangea33 » Mon Oct 30, 2017 9:18 am

tampaite wrote:
Mon Oct 30, 2017 7:18 am
Yes. Flood insurance is a waste of money unless you are IN an actual flood zone.
Respectfully, 50% of the homes that were significantly damaged in Houston were in "high" and "moderate" risk flood areas while not being in official "flood zones." A lot of this is the result of the Realtor lobby pitching a fit because homes in designated flood zones are harder to sell.

Know how much money the approximately 750,000 people who saved a couple hundred dollars a year on flood insurance will be paid to help rebuild?

https://qz.com/1063985/hurricane-harvey ... insurance/

The likelihood of me being killed this year is pretty low too. I still pay $500 a year for life insurance even though it isn't required by federal law. YMMV

TylerDavis
Posts: 203
Joined: Wed Nov 24, 2010 3:07 pm

Re: Buying a Home in a 500 year Flood Plain

Post by TylerDavis » Mon Oct 30, 2017 9:33 am

IF the flood plan maps are accurate, and there is a 1/500 chance of flooding in any given year, the probability that the home will flood at least once over a 30-year timeframe is about 6%

A 100-year flood plain house has about 25% chance of flooding at least once in 30 years

http://stattrek.com/online-calculator/binomial.aspx

User avatar
Pajamas
Posts: 2780
Joined: Sun Jun 03, 2012 6:32 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Pajamas » Mon Oct 30, 2017 9:41 am

student wrote:
Mon Oct 30, 2017 8:55 am
t is somewhat misleading. It is better for them to just say the probability of being flooded in a given year is 1/500.
I don't think most people understand how probability works, so that would seem pretty safe to them.
Or better yet, state the probability of being flooded in a given 10-year period, 20-year period and 30-year period.
Much better, except that it still doesn't account for changes in the environment and the fact that there have been three 500-year floods in three years in Houston.

I am not even comfortable calculating safe withdrawal rates based on past market conditions because we all know that past performance does not guarantee future results, much less the odds of flooding. Becoming near-penniless or being flooded is not something that I would want to play the odds on, because either one would be so devastating if it did occur.

runner3081
Posts: 781
Joined: Mon Aug 22, 2016 3:22 pm

Re: Buying a Home in a 500 year Flood Plain

Post by runner3081 » Mon Oct 30, 2017 9:44 am

tampaite wrote:
Mon Oct 30, 2017 7:18 am
harrad wrote:
Mon Oct 30, 2017 6:03 am
We have an option to buy a home in the Houston suburbs which is in a 500 year flood plain. The past few years when Houston had major flooding issues, the home or the street did not see flooding (tax-day flood, memorial-day flood and hurricane Harvey). I got this data from the previous owners and cross checked with sites showing the extent of flooding from these events.

FEMA flood plain maps show that the street in front of the home is in the 500 year flood plain and the home is 2 feet above the street surface. While we plan to get flood insurance, should we pass on this opportunity?
Yes. Flood insurance is a waste of money unless you are IN an actual flood zone.
Completely disagree. Flood insurance will be extremely cheap and covers a number of things (water related) that homeowner's doesn't. Our house was in AO (100 year) when we moved in 5 years ago. This last summer it was changed to the X500 (500 year zone). We received all of the mortgage paperwork pulling the flood requirement, but at only $277 per year, it seemed like a "no-brainer" to keep the flood insurance. We have a very hefty EF, but no way would it cover a house rebuild.

AlphaLess
Posts: 46
Joined: Fri Sep 29, 2017 11:38 pm

Re: Buying a Home in a 500 year Flood Plain

Post by AlphaLess » Mon Oct 30, 2017 9:48 am

Why encourage poor urban planning and bid up inefficient services like flood insurance?

Move to another area that does not have flood dangers at all.

AlphaLess
Posts: 46
Joined: Fri Sep 29, 2017 11:38 pm

Re: Buying a Home in a 500 year Flood Plain

Post by AlphaLess » Mon Oct 30, 2017 9:49 am

In the presence of regime shifts (such as the ones we are experiencing in our decade) old models are useless.

Nowizard
Posts: 1201
Joined: Tue Oct 23, 2007 5:33 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Nowizard » Mon Oct 30, 2017 9:54 am

Common advice among my construction friends is never buy property that is below the level of the road. Also, properties that are in flood plains need to be researched to determine when the research designating it as in the "500 year flood plain" occurred. This is due to the fact that if the area is in one with much new development, particularly strip malls or business with considerable concrete, the area may be much more vulnerable to flooding with much less water than was required when the determination was made. The same applies to neighborhoods not in a flood plain where there is considerable in-fill of older homes being torn down and multiple dwellings being constructed where there was previously only one.

Tim

User avatar
boomer
Posts: 80
Joined: Sun May 04, 2014 1:06 pm

Re: Buying a Home in a 500 year Flood Plain

Post by boomer » Mon Oct 30, 2017 9:58 am

I would be concerned about reselling the home and resale value when it is time to sell again.

ThriftyPhD
Posts: 164
Joined: Mon Jul 31, 2017 10:43 am

Re: Buying a Home in a 500 year Flood Plain

Post by ThriftyPhD » Mon Oct 30, 2017 10:15 am

I'm currently looking to buy a house, and many of the towns and neighborhoods around here are in 100 or 500 year flood zones. Looking at the flood maps, and listening to how our realtor talks about it, there are a lot of shenanigans. Homeowners and realtors will fight tooth and nail to get properties out of the 500 year zone, or to move from 100 year to 500 year. You would hope that the maps are drawn objectively, but that's clearly not the case. I've seen examples where the homeowner petitioned and got their house out of the flood zone, but the rest of the property is within the flood zone, completely surrounding the house. That doesn't make sense at all, but technically because of the reclassification flood insurance is no longer necessary. As I dug further into other listings, you can see that many are petitioning to get their homes out of flood zones. In reality, the zones should be extended even more than they are.

We stopped looking in entire neighborhoods. I don't care how 'cheap' flood insurance currently is, if I'm buying a home it's a long term investment and I don't see how they can keep flood insurance that low for the long haul. In addition, even with flood insurance I don't want my primary residence to be destroyed.

If there are other home-buyers like us, it is going to be difficult to sell these properties, and most likely increasingly difficult as time passes and water rises.

If you need to buy a home in Houston, and there are no properties outside of a flood prone area given the topography, look into how much it would cost to put the home on stilts.

runner3081
Posts: 781
Joined: Mon Aug 22, 2016 3:22 pm

Re: Buying a Home in a 500 year Flood Plain

Post by runner3081 » Mon Oct 30, 2017 10:25 am

ThriftyPhD wrote:
Mon Oct 30, 2017 10:15 am
I'm currently looking to buy a house, and many of the towns and neighborhoods around here are in 100 or 500 year flood zones. Looking at the flood maps, and listening to how our realtor talks about it, there are a lot of shenanigans. Homeowners and realtors will fight tooth and nail to get properties out of the 500 year zone, or to move from 100 year to 500 year. You would hope that the maps are drawn objectively, but that's clearly not the case. I've seen examples where the homeowner petitioned and got their house out of the flood zone, but the rest of the property is within the flood zone, completely surrounding the house.
Completely true. There are some higher end neighborhoods that essentially forced themselves out of the flood plain, while people across the street are still in it!

runner3081
Posts: 781
Joined: Mon Aug 22, 2016 3:22 pm

Re: Buying a Home in a 500 year Flood Plain

Post by runner3081 » Mon Oct 30, 2017 10:26 am

boomer wrote:
Mon Oct 30, 2017 9:58 am
I would be concerned about reselling the home and resale value when it is time to sell again.
I guess that depends on where you live. Here in AZ, there are plenty of places in a flood zone, but buyers don't bat an eye.

NightFall
Posts: 221
Joined: Wed Mar 12, 2014 4:38 pm

Re: Buying a Home in a 500 year Flood Plain

Post by NightFall » Mon Oct 30, 2017 11:01 am

Allison and Harvey were both extraordinary events in Houston. If the house survived both without flood damage, I would feel more confident foregoing it. However, as someone else pointed out, further development changes flood patterns. The fact that the street has flooded is not that surprising. Houston is designed to channel massive amounts of water. Most goes through the bayous. However, the streets are designed as a secondary drainage mechanism (don't park on the street). I know people that have had 2-3 foot rivers in the street in front of their houses. Houses were fine.

User avatar
Raymond
Posts: 1184
Joined: Mon Apr 16, 2012 6:04 am
Location: Texas

Re: Buying a Home in a 500 year Flood Plain

Post by Raymond » Mon Oct 30, 2017 11:02 am

tampaite wrote:
Mon Oct 30, 2017 7:18 am

Yes. Flood insurance is a waste of money unless you are IN an actual flood zone.
Unless the flood map is out of date, or developers have convinced the local government to manipulate the data, and so on.

"Study Finds FEMA Flood Maps Missed 75% Of Houston Flood Damage Claims Between 1999 And 2009" - Forbes.com

"Why Are FEMA’s Flood Maps So Horribly Flawed?" - Slate.com
"Ritter, Tod und Teufel"

student
Posts: 1333
Joined: Fri Apr 03, 2015 6:58 am

Re: Buying a Home in a 500 year Flood Plain

Post by student » Mon Oct 30, 2017 11:49 am

Pajamas wrote:
Mon Oct 30, 2017 9:41 am
student wrote:
Mon Oct 30, 2017 8:55 am
t is somewhat misleading. It is better for them to just say the probability of being flooded in a given year is 1/500.
I don't think most people understand how probability works, so that would seem pretty safe to them.
Or better yet, state the probability of being flooded in a given 10-year period, 20-year period and 30-year period.
Much better, except that it still doesn't account for changes in the environment and the fact that there have been three 500-year floods in three years in Houston.

I am not even comfortable calculating safe withdrawal rates based on past market conditions because we all know that past performance does not guarantee future results, much less the odds of flooding. Becoming near-penniless or being flooded is not something that I would want to play the odds on, because either one would be so devastating if it did occur.
I agree that it is not ideal but without further data, it is difficult to come up with a better model.

User avatar
Tamarind
Posts: 641
Joined: Mon Nov 02, 2015 2:38 pm

Re: Buying a Home in a 500 year Flood Plain

Post by Tamarind » Mon Oct 30, 2017 2:10 pm

harrad wrote:
Mon Oct 30, 2017 9:11 am
There is a big bayou about 0.4 miles from the subdivision and in the side of the subdivision (0.1 miles from the home), there runs a large canal which dumps into the bayou.
You seem to have a good grasp of what's involved in the decision. These features and neighborhood topography relative to them are key to understanding your risk.

What's your elevation relative to the banks of these features? To what extent did they flood in recent large storms? If they did, how far away is the nearest building that was flooded? What's your elevation relative to that building? Was there standing water in the street during recent large storms? How much? Did the storm drains back up anywhere in your neighborhood?

In an area as flat as Houston, an extra 6 inches of flood height in the next big storm can cover a LOT of distance on the ground.

harrad
Posts: 17
Joined: Mon Sep 29, 2014 6:50 am

Re: Buying a Home in a 500 year Flood Plain

Post by harrad » Mon Oct 30, 2017 3:37 pm

Tamarind wrote:
Mon Oct 30, 2017 2:10 pm
harrad wrote:
Mon Oct 30, 2017 9:11 am
There is a big bayou about 0.4 miles from the subdivision and in the side of the subdivision (0.1 miles from the home), there runs a large canal which dumps into the bayou.
You seem to have a good grasp of what's involved in the decision. These features and neighborhood topography relative to them are key to understanding your risk.

What's your elevation relative to the banks of these features? To what extent did they flood in recent large storms? If they did, how far away is the nearest building that was flooded? What's your elevation relative to that building? Was there standing water in the street during recent large storms? How much? Did the storm drains back up anywhere in your neighborhood?

In an area as flat as Houston, an extra 6 inches of flood height in the next big storm can cover a LOT of distance on the ground.
The home is 18" above the banks of the bayou. I drove around the area and homes close to the bayou saw flooding at the street (homes did not flood) but further away there had been no flooding even on the streets.

I was able to correlate the responses from talking to the neighbors with the image from NOAA (https://storms.ngs.noaa.gov/storms/harvey/index.html) showing a real time snapshot of the flooding during Harvey. Granted the snapshot does not show the worst case flooding in the neighborhood, it does give something to go by. As building happens in the west of where we live, we do realize the flood plain will move and we may be affected adversely.

We decided to go ahead with the goal of carrying flood insurance for the property - flood insurance runs about 450$. We are also cautiously optimistic as even if flooding were to occur, it would not dent our retirement accounts or emergency savings. Grateful for all the responses.

Post Reply