Blog · October 14, 2026 · Wisconsin
Sussex Flood Zone Map, Wisconsin: a practical guide
Flood zones are set by FEMA, and checking one near Lannon takes a few minutes.
Main page: Waukesha County, WI GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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Weighing a property around Lannon? A quick look at the Sussex flood zone map shows whether FEMA puts it in a high-risk zone, and no account is needed. What this Sussex guide covers: locating a parcel on FEMA's map, decoding A, AE and X, and matching it with the county parcel viewer.
Getting started with the Sussex flood zone map
Start with FEMA's Flood Map Service Center: type an address near Menomonee Falls, then open the map view for that panel. A tract near Pewaukee without an address is still easy to locate: pan from the closest town then click the parcel area.
The free map to start with
Property in and around Lannon appear on the Waukesha County parcel viewer, a viewer that needs no account. Closer to Menomonee Falls, type a street address, an owner's name or a parcel number, and the viewer zooms to the match. In and around Merton, the parcel card usually lists the owner of record, assessed acreage, the parcel number and in many cases the last transfer.
Who handles what
If the acreage or value on a parcel near Hartland looks off are handled by the county real property listing office, which maintains the tax roll. Building or septic questions for a lot near Lannon are for the local planning and health departments, depending on whether the land is inside town limits.
What to request from a seller
Ask the seller about past flood claims on the property near Menomonee Falls; getting a quote early keeps the budget honest.
Reading the legal description
Wisconsin follows the Public Land Survey System, which means a tract near Menomonee Falls is described by section, township and range. A standard section is about one square mile, roughly 640 acres, and a township holds 36 of them, though sections near Pewaukee can be irregular. Keep the legal description for land near Menomonee Falls for any title or survey request.
Taking the map into the field
Most viewers work in a phone browser, which helps when you're standing on land near Menomonee Falls, so load it before you lose signal. A printout of the tract near Hartland helps when you meet an owner or agent.
Backing up the map with records
The map is an index, not the title: recorded deeds, plats and easements covering ground around Menomonee Falls are filed with the Register of Deeds. Inherited tracts near Merton can go back through a long string of deeds, so a title company can sort it out before a purchase.
Sussex and the county around it
Sussex lies within Waukesha County, Wisconsin, so its parcels are on the county's map. For acreage around Lannon, city or town hall handles matters such as zoning, permits and utilities within town limits, while the county keeps the tax map. Acreage past the town limits toward Pewaukee generally follows county rules instead.
Zones on the Sussex flood zone map
Around Hartland, zones beginning with A or V mark the Special Flood Hazard Area, meaning a 1% or greater chance of flooding each year. For a tract near Hartland, a shaded X area is moderate risk, between the 1% and 0.2% annual chance floods; plain X, or C on older maps, means minimal mapped risk.
Matching the zone to the lot lines
FEMA doesn't draw property lines, so check the Waukesha County parcel viewer too to see exactly which lot near Menomonee Falls you're looking at.
Insurance, lenders and building
On ground around Hartland, get the Elevation Certificate if one exists: it records the building's elevation against the base flood. New construction in a floodplain near Brookfield can trigger elevation rules; check with the county or town building office early.
Limits of the parcel data
Acreage on the record is an assessed number; only a licensed surveyor sets the real corners for a parcel near Lannon. If you're looking near Brookfield, owner names and values update on a schedule, so a deed recorded last month might lag behind.
Low spots and local drainage
Creeks and ditches near Hartland aren't always studied in detail, so walk the land after rain. Marshy spots near Merton can limit building too; check the National Wetlands Inventory mapper for a first look.
Sussex: common questions
What if the flood map is wrong for my lot near Hartland?
In most cases, you can ask FEMA for a LOMA if surveyed elevations show the building near Pewaukee is above the BFE, and lenders accept the result.
What does an AE label mean for a lot near Merton?
Usually, AE is a Special Flood Hazard Area with a published base flood elevation, so builders near Menomonee Falls design to that elevation.
Does the county parcel map show flood zones around Menomonee Falls?
Good question; a flood layer may appear in the Waukesha County parcel viewer layer list, but FEMA's own map is the official source.
Is Zone X safe from flooding in Sussex?
Usually, shaded X is moderate risk and unshaded X is minimal risk; many owners near Brookfield buy coverage anyway.
Who keeps deeds for property in Sussex?
For land near Lannon, assessment goes to the county real property listing office and deeds to the Register of Deeds.
Open the official Waukesha County, WI 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.