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FEMA flood zones · North Dakota

Slope County, North Dakota Flood Zone Map

3 federal flood & hurricane disasters

Less than 1% of Slope County’s area is in FEMA’s high-risk flood zones.

Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.

Coastal high risk (V, VE)FloodwayHigh risk (A, AE)Moderate (X, 500-year)Minimal (X)Undetermined (D)

Shaded areas are FEMA’s mapped flood hazard zones in and around Slope County, North Dakota. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.

Federal disasters

10 federal disaster declarations since 1978, 3 of them floods, coastal storms or hurricanes.

DisasterBegan
Severe Winter StormOct 4, 2013
Severe Winter StormJan 20, 2010
Severe Winter Storm And Record And/or Near Record SnowOct 4, 2005
Hurricane Katrina EvacuationAug 29, 2005
Severe Flooding,severe Winter Storms, Snowmelt, Spring RainsFeb 28, 1997
Severe Winter Storms And Blizzard ConditionsJan 3, 1997
Storms, Ice Jams, Snowmelt & FloodingApr 17, 1978
Blizzard & SnowstormsFeb 16, 1978

Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.

Recorded flood events

1 since 1996: 1 river or area floods.

EventDateDamage
FloodJun 6, 2007$50,000

— = no damage estimate in the record. Source: NOAA Storm Events Database.

From the storm reports

Flood · Jun 6, 2007. Thunderstorms followed by showers and then areas of steady rain on June 6 and 7 resulted in flooding in parts of southern North Dakota. Five to six (5 to 6) inches of rain was common over the two day period.

National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.

The zones you’ll see on the map

Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.

Cross-section of a river floodplainDiagram: a river valley. The floodway is the channel and the land beside it; the 1%-annual-chance flood surface (the base flood elevation) covers the valley floor as zone A or AE; a narrow band higher up is shaded X, the 0.2% floodplain; higher ground is X.0.2% CHANCE A YEAR (500-YEAR)BASE FLOOD ELEVATION · 1% A YEARXAEFloodwayAEX
  1. A / AE Inside the 1%-a-year floodplain: about a 26% chance of flooding over a 30-year mortgage. AE has a mapped base flood elevation; plain A does not.
  2. Floodway The channel and the land beside it that has to be kept clear enough to carry the flood. Building here is tightly limited.
  3. X shaded The 0.2% (500-year) floodplain, plus some levee-protected and very shallow flood areas.
  4. X Outside both lines. No federal requirement to insure, which is not the same as no risk.

Every flood zone code explained →

Flood insurance in Slope County

If a building in Slope County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.

Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.