TMK guide · Land rules

FIRM panels and LOMAs

The official flood map sheet for a lot, and the letter FEMA issues when a lot sits above the flood.

A FIRM, or Flood Insurance Rate Map, is the official FEMA flood map. It is printed in panels, each a numbered sheet with its own effective date. The panel number and date are what an insurer, lender or permit reviewer asks for.

A LOMA, a Letter of Map Amendment, is FEMA's written finding that a building or lot on natural ground sits above the base flood elevation even though the map shows it in a flood zone. It is based on survey elevations. Land raised with fill uses a different letter, a LOMR-F.

Maps are revised over time. A lot can change zones when a new panel takes effect, so the effective date matters.

What the law says, and who keeps it

• FEMA Flood Map Service Center

What the ParcelSheet card shows

The flood zone from the current mapped layer. The panel number, its effective date and any letter of map change are Pro detail, with a link to FEMA's own record.

Who to ask

FEMA, through the Map Service Center, for a LOMA. A licensed surveyor for the elevation certificate a LOMA needs. The County floodplain manager for local rules.

See it on a real lot

• TMK 1-3-3-025-016, Pālolo, Oʻahu
• TMK 2-2-3-010-014, Pukalani, Maui
• TMK 4-4-2-016-063, Kapaʻa, Kauaʻi

Checked 2026-10-17. This page explains a term in plain words. It is not legal advice; the County or State office named above decides.

More land rules

• Special Management Area (SMA)
• State Land Use Districts
• FEMA flood zones and what X shaded means
• Tsunami evacuation and extreme tsunami zones
• Sea level rise exposure area
• Lava flow hazard zones 1 to 9
• CPR lots (condominium property regime)
• ʻOhana units and accessory dwelling units
• Shoreline setback
• Cesspool conversion (Act 125)
• Important Agricultural Lands (IAL)
• Conveyance tax
• Property tax classes by County
• TMK (Tax Map Key)