Blog · October 14, 2026 · Minnesota
The Washington County Flood Zone Map: a Minnesota guide
FEMA's free flood maps and the Washington County parcel viewer, used together for property near Dellwood.
Main page: Washington County, MN GIS & Parcel Viewer (official map link, Washington County facts and neighboring maps).
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Before you buy a house in Afton, add on to a barn near Stillwater, or price a lot along the creek bottoms near Maple Island, check the Washington County flood zone map. Here's how to read FEMA's map for a Washington County, MN property and match it to the parcel record.
Next: FEMA's search tool, the zone labels you'll see for Washington County, and how the parcel record confirms which tract you're on.
Look up the Washington County flood zone map step by step
Open the FEMA Flood Map Service Center and type a county street address, say one in Stillwater. If a property near Cottage Grove has no street number yet, search the nearest road and pan to it. For an irregular lot near Cottage Grove, the National Flood Hazard Layer viewer is easier to use, so you can see whether the shading reaches a house near Cottage Grove. Next, the Washington County ArcGIS parcel map confirms which Washington County parcel you're looking at. Match the Washington County lines and acreage to the FEMA view, since flood maps do not draw property lines in detail.
Finding the tract on the Washington County map
The county's own public map is the Washington County ArcGIS parcel map, built on an Esri ArcGIS web map, and it opens without an account for parcels in Cottage Grove and the rest of the county. Most people locate their Washington County tract fastest by searching an address in Bayport, then clicking the outline. Our Washington County, MN page keeps the official link and the maps next door to Bayport in one place.
What the flood zone letters mean
For a lot in Stillwater, the label matters more than the color: A and V zones are Special Flood Hazard Areas, meaning FEMA estimates a 1-percent annual chance of flooding. Zone AE near Cottage Grove means FEMA published a base flood elevation; plain Zone A means no detailed elevation was studied. Shaded Zone X around Stillwater is moderate risk, between the 1-percent and 0.2-percent annual chance lines. Unshaded Zone X near Cottage Grove is minimal risk.
Low ground and small streams around Stillwater
A creek near Cottage Grove that shows no detailed zone, which is why it's worth walking the ground after a heavy rain.
Questions to ask before buying in Washington County
For a house near Cottage Grove, ask the seller for any elevation certificate on file and the current flood insurance declarations page. Then call an insurance agent who writes policies around Bayport and get a quote using the zone and the county parcel address.
Reading the fine print on a Washington County panel
The FIRM panel for Washington County carries an effective date; if it's old, ask the county floodplain office whether new maps for land near Bayport are in progress. Floodways, shown as hatched areas on some panels, are the channel and nearby land that must stay open, and building there near Birchwood Village faces the strictest rules.
Insurance, permits and map changes
The zone shows up again when a loan on a house near Cottage Grove is underwritten. If a house near Cottage Grove is mapped in a high-risk zone and is financed by a regulated or federally insured lender, a flood policy becomes a loan condition; that applies where the local government around Cottage Grove is in the National Flood Insurance Program. Outside the A zones around Cottage Grove, insurance is a choice, not a mandate; pricing a policy for land near Cottage Grove is still worth a call. When a Washington County homesite is on a rise inside a mapped zone, FEMA's LOMA process allows a review, generally backed by an elevation certificate from a surveyor who works in Washington County. Building or filling inside a mapped zone near Stillwater frequently requires a permit and an elevation check, and the building office serving Cottage Grove explains the steps.
Washington County flood zones questions
Is Zone AE near Dellwood high risk?
Yes, a property near Dellwood in Zone AE is high risk: a 1-percent-annual-chance floodplain where FEMA lists a base flood elevation.
What is a base flood elevation for a Washington County property?
For a county property in Zone AE, the BFE is the height floodwater is expected to reach in the 1-percent-annual-chance flood, and a surveyor compares the building near Cottage Grove to it.
What if FEMA's map is wrong about my house near Dellwood?
An owner near Dellwood can request a Letter of Map Amendment from FEMA with elevation data, generally from a licensed surveyor.
Who prepares an elevation certificate for a house in Cottage Grove?
Hire a licensed surveyor or engineer who works in Washington County; ask the local floodplain office first in case one exists.
Does a 100-year floodplain near Dellwood flood only once a century?
No, ground around Cottage Grove mapped that way carries a 1-in-100 chance in any single year, so floods can come in back-to-back years.
Open the official Washington County, MN parcel map Washington County 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.