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What a Letter of Map Amendment (LOMA) Covers Under 44 CFR Part 70
A LOMA fixes a mapping error, not ground conditions: it corrects a flood map line drawn onto the wrong street or feature, with a 60-day federal response clock.
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What matters now
- A LOMA corrects a mapping error, not a change in actual ground conditions.
- The request must name the community, the map number, and the excluded property.
- FEMA must respond in writing within 60 days of receiving the applicant's data.
- Topographic change since the first flood map is excluded from this procedure.
- A LOMA skips the Federal Register unless base flood elevations also change.
A Letter of Map Amendment (LOMA) is a narrow administrative correction under 44 CFR Part 70. It is available only when a property was inadvertently placed inside a flood-hazard zone because the flood map’s curvilinear boundary line was transposed onto a street or other identifiable feature on the ground — never because the ground itself changed. The regulation describes this as the “transposition of the curvilinear line to either street or to other readily identifiable features” (44 CFR Part 70). A qualifying request must identify the community, the map number, and the specific property being excluded. FEMA must then respond in writing within 60 days of receiving the applicant’s supporting technical or scientific information. A LOMA does not, by itself, get published in the Federal Register — that only happens if the correction also changes base flood elevations under a separate part of the regulations.
This original record-reading guide is a general reading aid, not cited evidence. It does not depict a source record; the article text and source links provide the facts.
Key points
- A LOMA corrects a mapping error — the flood boundary line was drawn onto the wrong street or feature — not a change in actual ground conditions.
- The request must include the community name, the map number, and the property being excluded from the hazard zone.
- FEMA must notify the applicant in writing of its determination within 60 days after receiving the applicant’s technical or scientific information.
- Alterations from actual topographic change since the first flood map took effect are excluded from this procedure entirely.
- A LOMA does not trigger a Federal Register notice unless it also alters base flood elevations set under Part 67.
Eligible mapping errors
Part 70 limits this correction to one specific type of error: the map’s curvilinear flood-zone boundary was transposed onto the wrong street or other identifiable ground feature. The regulation’s own language is the “transposition of the curvilinear line to either street or to other readily identifiable features” (44 CFR Part 70). This is a line-drawing problem, not a factual dispute about whether the land floods.
What is excluded from this procedure
The same regulation draws a hard boundary around when a LOMA can be used at all. It states plainly that “these procedures shall not apply when there has been any alteration of topography since the effective date of the first NFIP map” (44 CFR Part 70). In other words, if the ground has physically changed — through fill, grading, construction, or any other alteration — since the community’s first National Flood Insurance Program map took effect, this administrative amendment route is not available.
What the request must identify
A LOMA request has to pin down the exact map being corrected. Part 70 requires “the number of the map” (44 CFR Part 70) as part of what must be specified, alongside the community and the excluded property, so the correction attaches to one identifiable map, not a general area.
The 60-day response clock
Once an applicant submits the required technical or scientific information, FEMA is on a fixed clock. The agency must “notify the applicant in writing of his/her determination within 60 days after we receive the applicant’s scientific or technical information” (44 CFR Part 70).
LOMA publication status
Unlike a Letter of Map Revision, a LOMA ordinarily does not create a Federal Register notice. The regulation specifies that the Federal Insurance Administrator “shall not publish a notice in the Federal Register that the FIRM for a particular community has been amended by letter determination pursuant to this part unless such amendment includes alteration or change of base flood elevations established pursuant to part 67” (44 CFR Part 70). So a straightforward line-transposition correction stays as a letter determination on file, not a published federal notice — publication is triggered only when base flood elevations themselves are also changed. For communities whose letter determinations were issued under this section but are not printed in the CFR itself, the regulation points readers to the List of CFR Sections Affected in the Finding Aids Section for that record (44 CFR Part 70).
What this article does not answer
This article explains only what the LOMA mechanism under Part 70 is and how it works procedurally. It does not revise a map’s flood elevations — that is a separate determination under Part 67. It does not say whether a Federal Register record will exist for any given case, since that only happens when base flood elevations are also altered. It says nothing about flood risk in general: the regulation settles only whether a parcel was drawn inside a boundary line it should not have been inside, not whether the area is prone to flooding. It does not evaluate whether any specific property is inadvertently included in a hazard zone or otherwise qualifies for a LOMA — that determination depends on facts specific to each parcel and map that are outside the scope of this explainer. And it does not address whether any specific property actually floods, sits in a Special Flood Hazard Area, requires flood insurance, or what such a policy would cost.