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(@joe-the-surveyor)
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When submitting information for an AE zone. How and what would you submit for this requirement?

*BFE Explanation
Please upload a detailed explanation of how the BFE was determined. This should include a copy of the effective FIS Profile (for riverine flooding sources) annotated with the scaled location of the subject structure or property or a copy of the FIS Summary of Stillwater Elevations Table (for stillwater flooding sources) with an annotation indicating the BFE for the subject of the eLOMA.

 
Posted : June 22, 2016 5:39 am
(@back-chain)
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In NC, there is a State website dedicated to flood data. From there, you can link to the FIS and download. I haven't done an eLOMA; however, I download the relevant data and keep as backup in my file for typical cert's.

You should find the profiles in the appendix. Locate your property and determine a distance up or downstream from the nearest flow obstruction (culvert, bridge, etc.). Then strike a vertical from your location to the flood profile. Next, a horizontal from that intersection to the y-axis and note your BFE.

Stillwater elevations are given by cross-section in the body of the FIS. Locate your stream's table in the FIS (generally a spreadsheet layout) and pull the cross section from the current FIRM (I think stillwaters are generally constant from xsect to xsect). Note BFE for your property from the Stillwater table.

I believe if neither of these exist for the subject parcel, you can use the number from the FIRM, itself. Whichever you choose: print, annotate, scan and archive.

 
Posted : June 22, 2016 6:22 am
(@paul-d)
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If you are submitting for a river, you will need to submit a copy of the FIRM showing the building location, a line to where you think the BFE should be determined on the centerline, and a measurement from the nearest cross section down (or up) the centerline. Then an annotated copy of the FIS profile showing a vertical line at the distance from the referenced cross section and a horizontal line showing where the BFE intersects the vertical line indicating what that elevation is.

Hope that makes sense.

 
Posted : June 22, 2016 6:43 am
 dcn
(@david-c-newell-rpls-ls-cfm)
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This is what I sent recently

Joe the Surveyor, post: 378568, member: 118 wrote: When submitting information for an AE zone. How and what would you submit for this requirement?

*BFE Explanation
Please upload a detailed explanation of how the BFE was determined. This should include a copy of the effective FIS Profile (for riverine flooding sources) annotated with the scaled location of the subject structure or property or a copy of the FIS Summary of Stillwater Elevations Table (for stillwater flooding sources) with an annotation indicating the BFE for the subject of the eLOMA.

Attached files

50-04 LOMA .pdf (1.1 MB) 

 
Posted : June 22, 2016 6:45 am
 dcn
(@david-c-newell-rpls-ls-cfm)
Posts: 143
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This is a copy of a recent one I did

Paul D, post: 378587, member: 323 wrote: If you are submitting for a river, you will need to submit a copy of the FIRM showing the building location, a line to where you think the BFE should be determined on the centerline, and a measurement from the nearest cross section down (or up) the centerline. Then an annotated copy of the FIS profile showing a vertical line at the distance from the referenced cross section and a horizontal line showing where the BFE intersects the vertical line indicating what that elevation is.

Hope that makes sense.

Attached files

50-04 LOMA .pdf (731.8 KB) 

 
Posted : June 22, 2016 6:46 am
(@rich)
Posts: 779
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Yup. I do something similar. I attach the FIS sheet with red lines on it and then I type a fast 'explanation' of how I measured the distance from the nearest cross section and yada yada. Takes 2 minutes.

 
Posted : June 22, 2016 8:52 am
(@joe-the-surveyor)
Posts: 1948
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Well here is the deal, this is on Long Island Sound, actually just inland of the shore, so its a AE 11 zone. But there are no FIS profiles of the sound that I can see.

 
Posted : June 22, 2016 9:20 am
(@paul-d)
Posts: 488
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Is it on the summary of stillwater elevations? If so, I print that page of the FIS and just highlight the appropriate flooding source and BFE.

 
Posted : June 22, 2016 9:22 am