FloodZoneMap.org

Gregory County, South Dakota Flood Zones

Check an Address in Gregory County

Enter any address in Gregory County, South Dakota to see its FEMA flood zone

The Flooding Character of Gregory County

Widespread flooding from heavy rainfall events is the dominant flood character in Gregory County. Recent events include significant flooding in June 2024, where multi-day rainfall totals of 5 to over 15 inches caused major to record river flooding and extensive overland flooding. In September 2019, a series of mid-level waves produced widespread heavy rainfall, with some locations recording over 8 inches in two days, leading to considerable flooding.

National Flood Insurance Program (NFIP) claims data shows that properties in Zone X (Unshaded) have experienced flood damage, with an average payout of $53,940 for claims with an average water depth of 0.0 feet. Homeowners and real estate agents should pay close attention to flood risk, particularly those with properties located near streams and rivers, or in areas that have experienced overland flooding.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Gregory County

6 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read South Dakota flood stories →

Flood Risk Data for Gregory County

Gregory County, South Dakota has recorded 15 flood-related events since 1996 according to NOAA's Storm Events Database, including 6 flash floods and 9 river or area floods. The county has received 24 federal disaster declarations, 9 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Gregory County Disaster History

FEMA Disaster Declarations (1976–2024)

Disaster Declarations
24
Flood/Coastal Disasters
9
Latest Disaster
Severe Storms, Straight-line Winds, And Flooding (2024-06-16)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Gregory County

DeclarationTypeDate
Severe Storms, Straight-line Winds, And FloodingFloodJun 16, 2024
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storms, Tornadoes, And FloodingSevere StormSep 9, 2019
Severe Storms, Tornadoes, And FloodingSevere StormJun 30, 2019
Severe Storms And FloodingFloodMay 21, 2019
Severe Winter Storm, Snowstorm, And FloodingFloodMar 13, 2019
FloodingFloodMar 11, 2011
FloodingFloodMar 10, 2010
Severe Winter StormSevere StormJan 20, 2010

Recorded Flood Events in Gregory County

NOAA Storm Events Database (1996–2025)

Total Flood Events
15
River/Area Floods
9
Flash Floods
6
Total Property Damage
$8.5M

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Gregory County

TypeDateDamage
FloodJun 21, 2024352.00K
FloodMar 13, 20191.38M
FloodSep 12, 2019205.00K
Flash FloodAug 9, 20195.00K
Flash FloodAug 9, 2019630.00K
FloodJun 1, 20190.00K
Flash FloodJul 12, 20180.00K
FloodJun 1, 20110.00K
FloodJul 1, 20110.00K
FloodAug 1, 20110.00K

Gregory County Flood History

Flood — Jun 21, 2024

A multi-day significant heavy rainfall event from June 20-22 resulted in widespread rain totals between 5 and 10 inches with pockets in excess of 15 inches across portions of southeast South Dakota, northwest Iowa, and southwest Minnesota. As rainfall reached area streams and rivers, major to record flooding was observed, devastating several towns and communities. Extensive overland flooding al...

Flood — Mar 13, 2019

Rainfall of one to three inches on frozen ground and into a snow pack with between 2 and 5 inches of liquid water equivalent resulted in considerable overland flooding.||One of the hardest hit areas was around Yankton, where a No Travel Advisory was issued for the city on March 13-14. Businesses along north Highway 81 toward Yankton Mall had considerable ponding of water. Water rescues were n...

Flood — Sep 12, 2019

A frontal zone remained locked in place under southwest flow aloft as a series of mid-level waves moved across the region over a three day period. Widespread heavy rainfall resulted and amounts reached two-day records for several locations including Platte (6.29 inches), White Lake (6.28 inches), Bridgewater (8.05 inches), Montrose (5.63 inches), Alexandria (8.30 inches), Madison (7.63 inches)...

Flash Flood — Aug 9, 2019

Scattered thunderstorms developed across central South Dakota during the late afternoon hours and moved southeast into an environment of deep mixed-layer instability and effective shear of around 50 knots in the evening. Storms transformed into short bowing segments as they moved along the main instability gradient toward the lower James River Valley.

Flood — Jun 1, 2019

During crop planting season, prolonged flooding led to the loss of or inability to plant crops across the area. Crop loss estimates provided by the United States Department of Agriculture.

Source: NOAA National Weather Service Storm Events Database.

Gregory County NFIP Flood Insurance Claims

Total Claims Filed
2
Total Paid Out
$107,880
Avg Claim
$53,940

Claims by Flood Zone

X Unshaded (Low)
2

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Gregory County

FEMA assigns flood zone designations to areas in Gregory County, South Dakota:

AE High Risk — 1% annual chance of flooding. Insurance required.

VE Very High Risk — Coastal flooding with wave action.

X (Shaded) Moderate Risk — 500-year floodplain.

X Low Risk — Outside major floodplains.

View all flood zone types →

Flood Insurance in Gregory County

Properties in Gregory County, South Dakota that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.

Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.

Visit FloodSmart.gov to find an agent and get a quote.