My property being confiscated by the feds

[Alan L.]

I think I have an OLD transit around here somewhere. Learned how to set it up and level it in ag during high school (for terracing and running sewer lines). I think the pad where my house is is higher than any place they show as the flood plain. According to my GPS today (which I agree is totally unreliable) with my car parked on the edge of the flood plain out by the road the elevation was 667 and on the slab of my driveway (which is about 4" lower than the house slab") was 670. Pretty close, I know the GPS is not that accurate. But I know how to use the transit if I can just find it. At least it will let me know if it seem worth hiring.

Visually it appears that from the edge of what they now say is the flood plain my house is uphill.

My biggest problem is that there is no base elevation. If FEMA would tell that the flood plain on my property is a xxx elevation and my house is higher than that, I should be able to get it changed. But no such base elevation exists. Thats what zone A is, it really means they don't really know but it might be subject to flooding, or at least a 1% chance each year.

Before we built, our surveyor put out a series of red flags which designated the boundary of the flood plain according to the FEMA maps based on lines on a map, not based on elevation readings which are not available. Our house is several feet higher than those flags.

 

[dmccarty]

I have had a hand held GPS tell me I was X number of feet above sea level while I was sitting in kayak on the ocean. The same GPS told me I was below sea level while floating in said kayak. :laughing:

I was hoping the resident TBN surveyors would have commented on this thread....

My understanding is that the survey GPSes are very accurate. Since you really do not care about locating the property lines which might require going back to a known monument, I really wonder if the GPS stations can simply tell you the elevation of the house.

If the GPS station can get the elevation, you would think it would not cost much to have the surveyor to fix the elevation of the house.

Later,
Dan

 

[charlz]

Made me curious :thumbsup:

My Garmin 60csx says my elevation with the unit sitting on my desk on the second floor is 2563ft. Lying in the drive way it is 2540ft. Thinks it knows my position within +-17ft.

Google Earth says 2529ft and the USGS National Map viewer says 2529ft as well.

USGS TNM 2.0 Viewer

Then I looked up a local 'Vertical Control Disk' Benchmark, found its location in Google Earth. The benchmark is reported to be 2598.17ft and Google Earth showed 2595ft for the general area around the location.


Sooooo, Google Earth might be 'good enough' to determine if you should bring in a survey company depending on how close it shows you are to the flood zone elevation.

 

[jonyyuma]

I have a Magellan 330 and believe the readings from it..I also went to look at the survey maps at the library.You are high up in Idaho, I read --- feet above sea-level.When in Louisiana it read "0" ...Don't know the exact specs for it?

 

[graculus]

Regular consumer GPS is not very accurate for altitude.

Regarding the flood re-categorization issue here's a San Francisco Bay Area TV story 7 On Your Side flood insurance investigation leads to bill with changes | abc7news.com which may be interesting.

 

[Snapper Head]

I think I have an OLD transit around here somewhere. Learned how to set it up and level it in ag during high school (for terracing and running sewer lines). I think the pad where my house is is higher than any place they show as the flood plain. According to my GPS today (which I agree is totally unreliable) with my car parked on the edge of the flood plain out by the road the elevation was 667 and on the slab of my driveway (which is about 4" lower than the house slab") was 670. Pretty close, I know the GPS is not that accurate. But I know how to use the transit if I can just find it. At least it will let me know if it seem worth hiring.

Visually it appears that from the edge of what they now say is the flood plain my house is uphill.

My biggest problem is that there is no base elevation. If FEMA would tell that the flood plain on my property is a xxx elevation and my house is higher than that, I should be able to get it changed. But no such base elevation exists. Thats what zone A is, it really means they don't really know but it might be subject to flooding, or at least a 1% chance each year.

Before we built, our surveyor put out a series of red flags which designated the boundary of the flood plain according to the FEMA maps based on lines on a map, not based on elevation readings which are not available. Our house is several feet higher than those flags.

It has been mentioned that if you want TRUE elevations documented, that you will need to contact a local Surveyor. The Engineering company that did the desktop flood plain study wants an obscene amount of money because they are a sizeable engineering company. They did not have a legal obligation to come out and measure elevations, as the existing data and newer methods of remote elevation determination are reasonably accurate and are considered a good baseline for such a study.

A survey firm (many call themselves "engineering", but they are truly survey companies) in your area will charge you on the order of $500 bucks to spend a day determining HIGHLY ACCURATE, true elevations. While it is true that the GPS you buy at WalMart is not overly accurate at elevation determination, a commercial level dual channel receiver with altimeter is. And transit shots from a prelaid polygon of the property will tie it in.

Give them the background story, and they will very likely keep the price around the 5 bill level. Typically a survey with a letter from an RPLS will run a couple of grand.

If you get an RPLS (Registered Public Land Surveyor) to stamp it with his seal and sign his name, you will very likely prevail in your cause, provided the elevations are above the minimum.

Big Al

 

[toddbailey]

I think I have an OLD transit around here somewhere. Learned how to set it up and level it in ag during high school (for terracing and running sewer lines). I think the pad where my house is is higher than any place they show as the flood plain. According to my GPS today (which I agree is totally unreliable) with my car parked on the edge of the flood plain out by the road the elevation was 667 and on the slab of my driveway (which is about 4" lower than the house slab") was 670. Pretty close, I know the GPS is not that accurate. But I know how to use the transit if I can just find it. At least it will let me know if it seem worth hiring.

Visually it appears that from the edge of what they now say is the flood plain my house is uphill.

My biggest problem is that there is no base elevation. If FEMA would tell that the flood plain on my property is a xxx elevation and my house is higher than that, I should be able to get it changed. But no such base elevation exists. Thats what zone A is, it really means they don't really know but it might be subject to flooding, or at least a 1% chance each year.

Before we built, our surveyor put out a series of red flags which designated the boundary of the flood plain according to the FEMA maps based on lines on a map, not based on elevation readings which are not available. Our house is several feet higher than those flags.

In the worst case you would be required to have a floodstudy done by an Licensed Engineer in conjunction with the surveying needed to do the floodstudy. If I where you I would contact your local surveying/engineering firm and go from there it will not cost you anything to ask for their advise.

Survey grade GPS equipment is highly accurate usually in the 1-2 cm range but it is highly expensive start at 15 grand and go up And it takes alot of training and exper. to learn how to operate correctly!

 

[beppington]

BTW when I had my 60AC property surveyed last June (see post #12 above), I stuck a stake in the ground at the approximate center of what my county's contour elevation maps show as the highest contour/ area on the property (i.e. that ~1 acre that's above the flood plain) & had the surveyor determine the ground elevation at that stake. He charged me something like $150 (but then he was already on site to do the usual property transaction survey).

 

[teg]

There appear to be lots of beach front properties covered by flood insurance even though they are sooner or later going to get washed away. Are flood insurance rates actually set according to risk of loss or are the folks inland subsidizing the beach front/river front owners?

Yes we do, We pay $1,700/year... for us to flood, Noah would be building another one...

 

[Alan L.]

It has been mentioned that if you want TRUE elevations documented, that you will need to contact a local Surveyor. The Engineering company that did the desktop flood plain study wants an obscene amount of money because they are a sizeable engineering company. They did not have a legal obligation to come out and measure elevations, as the existing data and newer methods of remote elevation determination are reasonably accurate and are considered a good baseline for such a study.

A survey firm (many call themselves "engineering", but they are truly survey companies) in your area will charge you on the order of $500 bucks to spend a day determining HIGHLY ACCURATE, true elevations. While it is true that the GPS you buy at WalMart is not overly accurate at elevation determination, a commercial level dual channel receiver with altimeter is. And transit shots from a prelaid polygon of the property will tie it in.

Give them the background story, and they will very likely keep the price around the 5 bill level. Typically a survey with a letter from an RPLS will run a couple of grand.

If you get an RPLS (Registered Public Land Surveyor) to stamp it with his seal and sign his name, you will very likely prevail in your cause, provided the elevations are above the minimum.

Big Al

Back before we built I wanted elevations but at least the surveyor that we used said he could not make a determination based on elevations because there are no "base elevations" in the area. I took this to mean that although he might be able to establish that house pad is 670, there is no elevation for the flood plain. Maybe technology has improved and I try this approach again. I'd like to shoot it myself first and here's why:

When I built the house there was no question in my mind that it was above the flood plain. And we raised it up some more. But whereas the old maps had about 10 of my 24 acres in the flood plain, the new map has probably 22 in the plain! Its like they raised it up several feet, so I can't be sure if it is now up to my house or not. The new map has my house totally inundated. I might understand if this were a major river, but its just a seasonal creek that begins only about 6 miles upstream.