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FEMA flood zone

FEMA flood zone

FEMA flood zone

Anyone have experience with changing a FEMA flood zone? I own property that FEMA changed partially into a flood zone in 2011. The problem is they put the high end of the property (about 10 acres) in the flood zone while the end 7' lower is not in the flood zone. The property has never flooded to my knowledge, and that's 50+ years worth. It looks like someone at FEMA just doodled on the map show a flood plain, without any basis in real elevations. I'm wondering if I should hire a local engineer to help or is it a wasted effort. Thanks.

RE: FEMA flood zone

Is the question with respect to obtaining a good rate for flood insurance, or with respect to getting a permit to build something?

It is possible to get the Flood Map Service to make corrections - Look up LETTER OF MAP AMENDMENT DETERMINATION DOCUMENT (LOMA). Never needed to do this, so I can not make a guess if it is worth your time and effort. Their is a Flood Insurance Study document that accompanies the FIRM it might provide some insight to your particular location.

If you are contemplating constructing something in the FIRM designated flood zone you will need to review your localities implementation of the national flood zone ordnance.

Most of the time your question gets worked out during the site plan review process by defining an elevation below which the structure must be flooding tolerant.

You should take another look at the latest FIRM at the link below, and make sure the 2011 FIRM is the current version.

The following are links relevant to the question.
FEMA flood zone discussion https://www.fema.gov/flood-zones
Flood Map Service Center https://msc.fema.gov/portal/home

RE: FEMA flood zone

Thanks for the reply. No construction contemplated, I was investigating using it as collateral for a loan and the bank insisted I get flood insurance, when it wasn't needed way back when I used a mortgage to buy it. I'd like to get it "corrected", if possible. It may affect future sale prospects of the property and it screwed up my borrowing plans.

RE: FEMA flood zone

TrussBridgeboy - is there a "ridge" down the middle of your property? You say the high end is at 10' and the low end is at 7'. Is there a line down the middle that's at 11 or 12'? FEMA has been going through and updating their mapping recently using more detailed and accurate modeling. It could be the source of the flood water is at a higher elevation and part of your property is part of an elevated plane capable of retaining water, while the lower portion is part of a drainage basin where the water is less likely to collect.

FacEngrPE is spot on with the Flood Insurance Study recommendation. They aren't always easy to find, but if you contact your local Emergency Management Department they should have a copy or know where you can get one. It will have detailed information about sources of water, flood depths, flow rates, flood ways etc.

RE: FEMA flood zone

TrussBridgeboy - Maybe you need to make sure you are not within the floodplain limits by hiring a local engineer/surveyor. If indeed your land is higher than the floodplain, you can hire an engineer/surveyor to prepare an elevation cert to officially remove a portion or all of the property out of the floodplain.

RE: FEMA flood zone

The property is roughly 200' wide by 1500' long. It has a small creek in a very deep ditch down the long side. It's all along a RR track so it's more like a drainage ditch than a creek. The RR is several feet below and along the long edge of my property. I just thought it very odd that the high end was shown as in the flood zone (along with part of my building) while the low end is not. Across the RR track is a mountain and the new FEMA map shows the flood zone extending up onto the side of the mountain too! My thought was to hire a local engineer/surveyor to provide some elevations or whatever but I didn't want to do so if it was a futile effort with FEMA. Thanks everyone for your input.

RE: FEMA flood zone


One key is whether there is a determined Base Flood Elevation (BSE) for your flood zone. If there is, the LOMA previously mentioned should be relatively easy to acquire with a survey correcting the elevations/contours mapped by FEMA and showing your structure is above that elevation.

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