Blog · October 14, 2026 · New Hampshire
Grafton County Flood Zone Map (New Hampshire)
How to check if a property in Grafton County sits in a FEMA flood zone, and what the answer means for a buyer near Bath.
Main page: Grafton County, NH GIS & Parcel Viewer (official map link, Grafton County facts and neighboring maps).
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A Grafton County flood zone map check belongs in the due diligence for any Grafton County property, from a house lot in Alexandria to farm ground near Bethlehem. You can check it yourself for any Alexandria address in a few minutes.
Below are the FEMA links, a plain reading of the zone labels, notes on where water shapes land around Alexandria, and short answers to common questions.
Where to see the official Grafton County flood zone map
FEMA's official flood maps for Grafton County are free at the FEMA Flood Map Service Center. If a parcel near Alexandria has no street number yet, search the nearest road and pan to it. If the PDF panel for Grafton County is hard to read, FEMA's National Flood Hazard Layer viewer draws the zones over aerial imagery, so you can see if the shading reaches a house near Alexandria. Then open the NHDOT Parcel Mosaic Viewer for Grafton County to confirm the parcel near Bethlehem. Laying the county parcel outline beside the FEMA shading lists if a homesite near Alexandria sits above or inside the zone.
Step one: the free Grafton County viewer
Grafton County parcels are viewed through a statewide map, the NHDOT Parcel Mosaic Viewer; zoom toward Benton to reach them. The Grafton County site lists a disclaimer before the map; click through to reach parcels near Benton. Use the search box for an address in Benton or a parcel number, or simply zoom in and click a parcel near Alexandria. Our Grafton County, NH page keeps the official link and the maps next door to Alexandria in one place.
What the flood zone letters mean
On the FIRM covering Grafton County, zones that start with A or V are Special Flood Hazard Areas, land with a 1-percent chance of flooding in any given year (the base or 100-year flood). A surveyor working near Bethlehem uses the base flood elevation printed for AE zones; unnumbered A zones don't have one. If a Grafton County parcel lists shaded Zone X, it falls between the base flood and the 500-year flood. Clear, unshaded X near Bethlehem is outside the 500-year floodplain.
Waterfront parcels near Alexandria
Parcels touching Squam Lake deserve a FEMA check before anything else in Grafton County. Lines on those Grafton County parcels commonly follow the water, so part of the tract can be mapped as high risk. A low spot on a Grafton County tract outside any mapped zone, so treat an unmapped channel as a reason to ask questions, not proof the ground stays dry.
Seller questions about flood history
For a house near Benton, ask the seller for any elevation certificate on file and the current flood insurance declarations page. An agent working in Grafton County can quote flood coverage once you know the zone for the lot near Benton.
When the map affects a deal
Insurance is the practical stake for a Grafton County buyer. When a structure near Alexandria is mapped in a high-risk zone and is financed by a regulated or federally insured lender, flood insurance is mandatory under the Flood Disaster Protection Act, wherever the community joins the NFIP. In Zone X near Bethlehem, federal rules don't require a policy, although some lenders require it anyway. If a building near Alexandria sits above the flood line, FEMA's LOMA process allows a review; a surveyor near Alexandria can supply the elevation data. Building or filling inside a mapped zone near Bethlehem has to meet local floodplain rules, so call the county or the town office in Bethlehem before work starts.
Quick answers for Grafton County
Can I see flood zones on the Grafton County GIS map?
Check the layer list in the NHDOT Parcel Mosaic Viewer; if Grafton County includes a floodplain layer, confirm the zone on FEMA's map anyway.
What does 100-year flood mean for Grafton County land?
Not at all; a Grafton County tract in that zone carries a 1-in-100 chance in any single year, not a once-a-century schedule.
Can I build in a flood zone in Grafton County?
Often, but local floodplain rules apply; ask the county or town building office in Bath well before you buy.
Can a flood zone in Grafton County be changed?
For a lot in Bath, hire a surveyor for an elevation certificate, then file a LOMA request with FEMA.
What is a base flood elevation for a Grafton County property?
Near Ashland, it is the projected water surface in the base flood, and a surveyor compares the building near Bath to it.
My house near Ashland is in Zone X. Is insurance required?
FEMA does not require it for a Zone X lot in Bath, but coverage is available and some lenders ask for it.
Open the official Grafton County, NH parcel map Grafton 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.