Blog · October 14, 2026 · New Hampshire
Merrimack County Flood Zone Map in New Hampshire
Look up any Merrimack County address on FEMA's flood map, read the zone, and match it to the parcel record for land around Andover.
Main page: Merrimack County, NH GIS & Parcel Viewer (official map link, Merrimack County facts and neighboring maps).
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Land along the creek bottoms near Loudon and the flats outside Bow are where a Merrimack County flood zone map lookup matters most. You can check it yourself for any Bow address in a few minutes.
Below are the FEMA links, a plain reading of the zone labels, notes on where water shapes land around Bow, and short answers to common questions.
Where to see the official Merrimack County flood zone map
FEMA's official flood maps for Merrimack County are free at the FEMA Flood Map Service Center. Search returns the effective FIRM panel for the spot in Merrimack County, plus any pending changes FEMA has posted. For an interactive view of Merrimack County, FEMA's National Flood Hazard Layer viewer draws the zones over aerial imagery, which shows how much of a Merrimack County parcel sits inside the zone. Switch to the NHDOT Parcel Mosaic Viewer and find the same piece of ground near Bow. The Merrimack County record gives the parcel identifier and legal description that an insurer or lender near Bradford may ask for.
Step one: the free Merrimack County viewer
Merrimack County parcels are viewed through a statewide map, the NHDOT Parcel Mosaic Viewer; zoom toward Boscawen to reach them. The Merrimack County site shows a disclaimer before the map; click through to reach parcels near Boscawen. Use the search box for an address in Boscawen or a parcel number, or simply zoom in and click a piece of ground near Franklin. Bookmark our Merrimack County page too; it tracks the official New Hampshire link if it moves and lists the maps around Boscawen.
High, moderate and minimal risk in Merrimack County
For a lot in Bradford, the label matters more than the color: A and V zones are Special Flood Hazard Areas, land with a 1-percent chance of flooding in any given year (the base or 100-year flood). Zone AE near Bow means FEMA published a base flood elevation; plain Zone A means no detailed elevation was studied. Shaded Zone X around Bradford sits in the moderate band between the 100-year and 500-year floods. Unshaded Zone X near Bow is minimal risk.
Unmapped creeks in Merrimack County
Small streams and ditches near Bradford may not be studied in detail can still flood; FEMA says moderate- and low-risk areas still carry risk.
A short buyer checklist for Andover
Request any past flood claims history for a Merrimack County property before closing; it tells you more than the map alone. Then call an insurance agent who writes policies around Andover and get a quote using the zone and the county parcel address.
Reading the fine print on a Merrimack County panel
Look at the effective date printed on the county panel, since a new study can redraw zones around Bradford. A floodway on a county panel marks the part of the floodplain that carries the main flow, and it is treated more strictly than the rest of the zone near Loudon.
Flood insurance and building rules in Merrimack County
The zone shows up again when a loan on a house near Bow is underwritten. If a house near Bow sits in a Special Flood Hazard Area and carries a federally backed mortgage, flood insurance is mandatory, as long as Merrimack County or the town participates in the NFIP. For a Merrimack County home in shaded or unshaded X, coverage is optional, although a lender in New Hampshire can still ask for it. Where a structure near Bradford looks higher than the shading suggests, a Letter of Map Amendment request is the formal route, usually backed by an elevation certificate from a surveyor who works in the county. New construction in a Merrimack County Special Flood Hazard Area has to meet local floodplain rules; the Merrimack County floodplain administrator can say what applies.
Merrimack County flood zones questions
What does Zone AE mean on a Merrimack County flood map?
For a Merrimack County parcel, Zone AE means a Special Flood Hazard Area with a 1-percent annual chance of flooding and a published base flood elevation.
Where can I see flood zones for land near Franklin?
Look it up at FEMA's Flood Map Service Center, then match the parcel lines in the NHDOT Parcel Mosaic Viewer; for land near Franklin, a zone starting with A or V is high risk.
Do I need flood insurance in Zone X in Merrimack County?
FEMA doesn't require it for a Zone X lot in Concord, but coverage is available and some lenders ask for it.
What does 100-year flood mean for Merrimack County land?
No; land near Franklin in the 100-year floodplain has a 1-percent chance of flooding every year, not a once-a-century schedule.
Can I build in a flood zone in Merrimack County?
Often, but local floodplain rules apply; ask the county or town building office in Concord well before you buy.
How do I challenge a flood zone for a lot in Concord?
FEMA reviews requests such as a LOMA for Merrimack County properties; start with an elevation certificate.
Open the official Merrimack County, NH parcel map Merrimack 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.