FEMA flood zones · Montana

Rosebud County, Montana Flood Zone Map

12 flood insurance claims·$15,452 paid·4 federal flood & hurricane disasters

Less than 1% of Rosebud 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 Rosebud County, Montana. 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.

How Rosebud County floods

Flash flooding and river flooding from spring snowmelt, ice jams, and heavy rainfall shape the flood risk in Rosebud County, Montana. NOAA records from the last 30 years document 16 flash flood events and 12 general flood events.

Significant historical events illustrate these hazards. In June 2019, heavy rain over the Big Horn Mountains caused severe runoff, pushing the Tongue River to a crest of over 11 feet and flooding areas from Birney to southeast of Colstrip. In March 2014, a rapid warm-up following a cold winter and heavy snow triggered widespread snowmelt and ice-jam flooding, impacting the Otter Creek area.

Federal insurance claims data shows impacts across different zones. Zone A properties recorded 5 claims with an average payout of $909 and an average water depth of 12 inches. Zone X properties logged 4 claims averaging $3,236 with an average water depth of 1 inch, while properties with an unknown zone recorded 3 claims averaging $2,417 with an average water depth of 0 inches. Property owners located near rivers, creeks, and streams, as well as those in designated flood zones, should pay the closest attention to these recurring flood risks.

Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.

How deep the water got

outlet80″ door12″24″36″48″60″72″84″

In flood insurance claims here that reported a flood depth, the average was 8 inches.

Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.

Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.

Flood claims, year by year

The worst year was 2014, with 4 claims and $2,082 paid, the year of Ice Jams and Flooding.

1978: 1 claims1997: 3 claims2011: 2 claims2014: 4 claims2018: 1 claims2019: 1 claims1980199020002010

Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.

In their words

1 NOAA storm reports from Rosebud County describe what happened, in the words of the forecasters who covered it. Read the Montana flood stories →

Federal disasters

14 federal disaster declarations since 1978, 4 of them floods, coastal storms or hurricanes.

DisasterBegan
Richard Spring FireAug 10, 2021
Snider/rice Fire ComplexSep 3, 2020
Ice Jams And FloodingMar 1, 2014
FloodingMay 19, 2013
Ash Creek FireJun 25, 2012
WildfireJun 25, 2012
Severe Storms And FloodingApr 4, 2011
Hurricane Katrina EvacuationAug 29, 2005

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

Recorded flood events

28 since 1996: 16 flash floods and 12 river or area floods.

EventDateDamage
FloodJun 1, 2019—
FloodMar 8, 2014—
FloodMar 6, 2014—
FloodMay 30, 2013—
Flash FloodMay 29, 2013—
Flash FloodAug 2, 2013—
FloodJun 1, 2013—
FloodFeb 22, 2012—

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

From the storm reports

Flood · Jun 1, 2019. Very heavy rain over the Big Horn Mountains resulted in significant runoff into the Tongue River. The river crested just over 11 feet which was 4 feet higher than the record crest of 7.3 feet set in 2011. Flooding occurred along the Tongue River from the Birney area to just southeast of Colstrip.

Flood · Mar 8, 2014. After a very cold winter resulting in area rivers, streams and creeks freezing, early March began with some heavy snow followed by a rapid warm-up. This warm-up resulted in snowmelt and ice-jam flooding over area rivers, creeks and streams that continued into the middle of the month. While many areas experienced flooding, the locations that were most impacted by flooding included Park County, areas along the Musse…

Flood · Mar 6, 2014. After a very cold winter resulting in area rivers, streams and creeks freezing, early March began with some heavy snow followed by a rapid warm-up. This warm-up resulted in snowmelt and ice-jam flooding over area rivers, creeks and streams that continued into the middle of the month. While many areas experienced flooding, the locations that were most impacted by flooding included Park County, areas along the Musse…

Flood · May 30, 2013. Two Pacific low pressure systems brought abundant moisture to the Billings Forecast Area during the end of the month. This resulted in flooding of small streams and creeks, as well as across burn scar areas. The two storm systems resulted in above normal precipitation for the month.

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 Rosebud County

If a building in Rosebud 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.