I personally wouldn??t use OPUS to do a flood certificate. ?ÿIt might be a good check. ?ÿ
@aliquot?ÿ
Call it what you want. Deception, incompetence, stupidity. You tell a Government employee he or she is guilty of Fraud. They listen up. You tell them there incompetent they just hate you and vindictive.
incompetence, stupidity
The practice of not showing the bench marks upon which the zones are based is one or both of those.
Two things to note.
A BFE doesn't follow contours and neither do floods.?ÿ
FIRM panels don't tell us where flooding will happen. They tell insurance companies the rating to establish premiums. Hence the name Flood Insurance Rate Map.
Planning authorities obtain favorable community ratings by adopting FEMA standards for flood plain development. There are processes to deal with the known issues in the data, but they don't work if you wait until a demo order shows up to put in the work and figure out what's up.
OPUS is a great tool for obtaining moderately accurate absolute vertical information. It is worse than useless without validation, especially when mixing with data from other sources.
I believe that for most areas the Gov utilized a mixture of Quad maps and Aerial data. In PLSS areas any way.?ÿ
"FIRM panels don't tell us where flooding will happen. They tell insurance companies the rating to establish premiums. Hence the name Flood Insurance Rate Map."
How many surveyors, engineers, municipal officials or homeowners understand that statement?
Ken
?ÿ
@bill93 well there are no benchmarks shown on NAVD88 FIRM maps available to me.
That is why you need to search out the older maps via any source possible.?ÿ In my case, I copied the old maps during the time they were available everywhere.?ÿ Of course, this only works for jobs in those specific areas.?ÿ That covers most of the elevation certificate jobs I receive.
For other areas I refer to local benchmark data that should have been based on the same Government-recognized benchmarks.
FIRM maps are better than nothing.?ÿ That sums it up completely.
I own property in a city that has a new FIRM map dated 2010.?ÿ That is a fallacy.?ÿ The Government completed their analysis in 2005.?ÿ They spent five years going through various reviews, including local public meetings, before publishing in 2010.?ÿ We had a tremendous river flood occur in 2007 that exceeded the flood boundary on the old FIRM map by two feet in those parts of the city based on river flooding.?ÿ The part primarily based on a creek was as much as six feet lower than the old flood boundary.?ÿ It was too late to include the 2007 data.
The lots that I own were shown to be about one-third in the flood plain on the old map.?ÿ The 2010 map shows them to be out completely.?ÿ Last year we had a flood event.?ÿ Every inch of those lots was under water of varying depths.?ÿ It will be about 2030 or later before an updated FIRM may be published.
Several other cities had similar and worse flooding in 2007.?ÿ Six and eight feet higher than the magic old FIRM number, in fact.?ÿ We had been scheduled to survey a property with a house that had a LOMA showing it to be out of the flood plain.?ÿ That job was canceled as the house had water about four feet deep above first floor level.?ÿ We drove by a couple of weeks later to see numerous houses in that part of town abandoned.
I've often proposed that after any flood event that sets a new high-water record, the governments should send people out to permanently mark that level on buildings, trees, lamp posts, or whatever.?ÿ You would no longer need analysts sitting in offices staring at incomplete and hypothetical data, and any fool could see what they were risking by buying a property. Why go through all this nonsense of calculated BFE measured off who-knows-what benchmark when you could find a high-water mark within a short distance of any property?
Where is the deception??ÿ
When you accuse someone of fraud when there is no intentional misdeeds, you loose your professional credibility. When you raise concerns, point out problems, and suggest solutions you get attention. No one in a decision?ÿ making position is going to hear what you are saying because you are accusing them of breaking the law. You will either lose all credibility, because they obviously are not, or they will be so concerned about protecting themselves they will not pay any attention to the substance of what you are saying. They certainly will not look to you to help with the solutions (they should).?ÿ
Consider the difference between a fellow surveyor, accusing you of fraud in public and to other surveyors, and them contacting you and letting you know you may have missed something. It the latter situation I hope you would politely listen and consider what they have to say. In the former I wouldn't?ÿ blame you for not engaging.?ÿ
@holy-cow The benchmarks shown on the old FIRM maps are NAVD27 vintage and have to be converted (which NGS has a nifty conversion program to do so on their website) however I have found the old benchmarks(which were set by a Contractor) to be super bogus. The benchmarks shown on quad seem to be pretty good, however there is no published report on them and they're only shown to a foot. I feel comfortable using them because they have the appropriate significant figures and match the contour map, which was probably drawn using them for vertical control
@aliquot Well FEMA is open about their map accuracy. NGS is mum about their benchmark accuracy. Evidently someone is training local government folks to use those products for a use they were not intended for. What do you call that?
Want to buy my snake oil? It cures cancer.
@bill93?ÿ
I agree with you. My client has pictures of the 2011 flood, highest on record. The County is using the bogus FEMA FIRM maps and NGS benchmarks of dubious accuracy over that.
@holy-cow So your saying FIRM maps aren't accurate to 0.4 feet?????
Yeah, you have brought up a letgitime issue, but who is commiting fraud?: The "intentional perversion of truth in order to induce another to part with something of value"
@aliquot?ÿ
You're kind of sidetracked. The use of the word Fraud is a different subject. What are you a lawyer?
Trying to help you. You have things to say that should be heard. I want?ÿ them to listen to you.?ÿ
Being side tracked is almost guaranteed to happen when you accuse some one of breaking the law.?ÿ
@aliquot Thanks, I need all the help I can get. I'm now convinced there's a problem. I'm not quite sure what process to use to fix it. Maybe get FEMA to put a disclaimer on their FIRM maps?