Blog · October 14, 2026 · Idaho
Reading the Lemhi County Flood Zone Map for a parcel
The zone on FEMA's map affects insurance, building and resale near Salmon National Forest.
Main page: Lemhi County, ID GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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Weighing a property around Salmon? The Lemhi County flood zone map tells you whether the lot falls inside a mapped floodplain, and the lookup is free. What this Lemhi County guide covers: locating a parcel on FEMA's map, reading the zone codes, and confirming the outline on the county map.
Where the Lemhi County flood zone map lives
Flood zones come from FEMA's Flood Map Service Center: type an address near Leadore, and choose the dynamic map. A tract near Leadore without an address is still easy to locate: search the nearest road then click the parcel area.
Where the parcel data lives
Go first to the Lemhi County ArcGIS parcel map; it covers every assessed parcel from Salmon to Gibbonsville. Without an address in hand, follow the nearest road on the aerial and select the outline, for land near Salmon National Forest included. Near Cobalt, copy the parcel ID while you have it open; every clerk in the county asks for it first.
Reading the legal description
Idaho follows the Public Land Survey System, so rural legal descriptions near Challis National Forest cite section, township and range. Each section is nominally a mile square, about 640 acres, and a township holds 36 of them, though real sections near Salmon National Forest vary in size. Write down the legal description for the tract near Salmon National Forest when you talk to a surveyor.
Backing up the map with records
The map is an index, not the title: deeds, plats and easements for land near Carmen are kept by the County Recorder (the county clerk serves as recorder). For a home near Gibbonsville, use the book and page listed on the parcel record so staff can find the deed fast.
What the map can't tell you
On ground around Challis National Forest, acreage on the record is an assessed number; only a licensed surveyor can set the real corners on the ground. Owner names and values update on a schedule, so a recent sale near Carmen can take weeks to appear.
Offices that can help
Deeds, mortgages and recorded plats for land near Challis National Forest sit in the index kept by the County Recorder (the county clerk serves as recorder), often with an online index. Building or septic questions for a lot near Salmon are for the local planning and health departments, town or county, depending on location.
Using it on a phone
Most viewers work in a phone browser, which helps when you're standing on land near Leadore, but coverage can be spotty out of town. A printout of the tract near Elk Bend keeps working without signal.
Decoding the flood zone labels
For a parcel near Cobalt, any A or V zone mark the Special Flood Hazard Area, land with a 1-percent chance of flooding in any year. In and around Salmon National Forest, shaded Zone X is moderate risk, roughly the 100- to 500-year range; unshaded X means minimal mapped risk.
When a parcel crosses a boundary
The county borders Butte County, Clark County, Custer County, Idaho County, and Valley County, and each of those keeps its own parcel map, especially near Gibbonsville. A tract near the line by Gibbonsville may show up across two assessors' files, so check the adjacent map before you assume the acreage. For land near Salmon, our state page links each bordering county map across Idaho.
Beyond the mapped zones
Creeks and ditches near Cobalt may not have detailed mapping, so walk the land after rain. Marshy spots near Leadore can limit building too; the National Wetlands Inventory mapper shows mapped wetlands.
Matching the zone to the lot lines
FEMA doesn't draw property lines, so check the Lemhi County ArcGIS parcel map too to see exactly which lot near Salmon National Forest you're looking at.
A short flood checklist
Closer to Elk Bend, request about past flood claims before closing; an insurance quote early keeps the budget honest.
What a flood zone means for a buyer
For a home near Leadore, an Elevation Certificate from a surveyor helps: it records the building's elevation against the base flood. Building or adding on near Salmon in a mapped zone usually means extra permit review; ask the local floodplain administrator before you plan.
Questions about the Lemhi County flood zone map
What is the difference between Zone A and AE near Challis National Forest?
If the land is near Salmon, both are high-risk zones, but only AE has a base flood elevation; unnumbered A zones don't list one.
Do I need to worry about flooding in Zone X around Elk Bend?
In most cases, X zones around Targhee National Forest are lower risk, not no risk; FEMA notes that a large share of claims come from these areas.
Can I see flood zones on the Lemhi County ArcGIS parcel map?
It depends, but a flood layer may appear in the Lemhi County ArcGIS parcel map layer list, though it can lag behind FEMA's current panels.
Can I challenge a flood zone near Carmen?
Good question; FEMA's LOMA process is the usual route when a building near Leadore sits above the base flood elevation; it starts with an elevation survey.
Who keeps deeds for property in Lemhi County?
For a tract near Leadore, values are the County Assessor's job; recorded documents belong to the County Recorder (the county clerk serves as recorder).
Open the official Lemhi County, ID parcel map See it in the Platbookmapper directory
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey, especially for fences, setbacks, or boundary disputes.