Blog · October 14, 2026 · Illinois
Using the Alton Flood Zone Map
The zone on FEMA's map affects insurance, building and resale near East Alton.
Main page: Madison County, IL GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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Ahead of any purchase around Wood River, pull up the Alton flood zone map: FEMA's zone label affects insurance, permits and resale. This city guide covers: finding the address on FEMA's map, decoding A, AE and X, and confirming the outline on the county map for land near Troy.
Getting started with the Alton flood zone map
If you'd rather pan and zoom, try the National Flood Hazard Layer viewer, which draws the zones over aerial imagery. A tract near East Alton without an address is still easy to locate: zoom in from Interstate 255 and click the spot.
Getting to the right map
Go first to the Madison County parcel viewer; it maps every assessed parcel in the county, East Alton included. For acreage around Bethalto, type a street address, an owner's name or a parcel number, then pick the result to center the map on it. For a home near Hartford, a pop-up or side panel typically gives the owner of record, acreage on the tax roll, the parcel number and in many cases the last transfer.
Where Alton fits in
The city lies within Madison County, Illinois, which means parcel data comes from the county, at least around Collinsville. For property near East Alton, the municipality handles things like zoning, permits and utilities for lots inside the boundary, while the county keeps the tax map. Lots just outside the city limits near East Alton generally follows county rules, not municipal ones.
Legal descriptions in Illinois
Illinois follows the Public Land Survey System, so deeds around Wood River reference sections and townships. Each section is nominally a mile square, about 640 acres, and a township holds 36 of them, though corrections make some sections near Godfrey odd-sized. Keep the legal description for land near Godfrey for any title or survey request.
A short flood checklist
Ask the listing agent whether the home has flooded on the property near East Alton; an insurance quote early avoids surprises.
Zones on the Alton flood zone map
For a parcel near Bethalto, any A or V zone are Special Flood Hazard Areas, land with a 1-percent chance of flooding in any year. For a tract near Roxana, a shaded X area is moderate risk, roughly the 100- to 500-year range; unshaded X means minimal mapped risk.
Offices that can help
Anything recorded against property around Roxana come from the county Recorder of Deeds (in many counties the County Clerk and Recorder), sometimes only in person. Questions about what you can build around Godfrey are for the local planning and health departments, and the answer depends on jurisdiction.
Backing up the map with records
For anything that matters, request the recorded deed through the county Recorder of Deeds (in many counties the County Clerk and Recorder); the viewer just points to it, and that holds around Godfrey too. If the land is near Godfrey, have ready the instrument number shown in the record panel to skip a name search.
A quick look at the area
Edwardsville serves as the county seat, where most land records are kept. Smaller places on the map include East Alton, Wood River, Godfrey, and Bethalto, where town lots give way to larger tracts. Around 262,752 people live in Madison County (Census Bureau estimate, 2023) across roughly 716 square miles. Madison County dates to 1812, and some chains of title near Roxana are long. Places such as Mississippi River and Horseshoe Lake help you orient on the aerial around Godfrey.
Use the county map alongside FEMA
FEMA's map shows zones but not ownership, so pair it with the Madison County parcel viewer for the outline of the tract near Hartford.
Insurance, lenders and building
For a tract near Roxana, get the Elevation Certificate if one exists: it compares the building to the BFE. Building or adding on near Bethalto in a mapped zone usually means extra permit review; call the permitting office early.
Beyond the mapped zones
Low-lying fields near Bethalto may not have detailed mapping, so ask neighbors about past flooding. Wetlands near Wood River can limit building even outside a flood zone; the National Wetlands Inventory mapper shows mapped wetlands.
Frequently asked
How can I tell if a house near Godfrey is in a flood zone?
Usually, search the address near Bethalto on FEMA's Flood Map Service Center; then confirm the parcel on the county viewer.
What is a base flood elevation around East Alton?
For most people, a BFE near Roxana tells builders how high the lowest floor should be, and an Elevation Certificate compares the building to it.
Does the county parcel map show flood zones around Roxana?
Good question; a flood layer may appear in the Madison County parcel viewer layer list; confirm a lot near Hartford on FEMA's map either way.
When is flood insurance required near Troy?
Usually, lenders generally require it for buildings near Wood River in a Special Flood Hazard Area when the loan is federally regulated or insured, in communities that take part in the NFIP.
Where do I find the parcel number for land near Wood River?
It's the number the Supervisor of Assessments, working with township assessors uses to track a tract near Bethalto, and it's on the record panel and tax bills.
Open the official Madison County, IL 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.