Enter any address in Washington County, Iowa to see its FEMA flood zone
Flash flooding from heavy rainfall events is the primary flood concern in Washington County, Iowa. Between 2004 and 2023, NOAA Storm Events data recorded 32 flood events and 29 flash flood events. For example, on July 20, 2025, heavy rain led to flash flooding in parts of the county. Additionally, widespread flooding occurred in late May and early June 2019 due to persistent rainfall and saturated soils, causing several rivers to exceed flood levels.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A experienced the highest average water depths and payouts, with an average of 18.8 feet of water and an average claim of $10,236. While Zone X_UNSHADED had fewer claims, the average payout was higher at $15,756, with an average water depth of 1.3 feet. Residents in areas designated as Zone A, as well as those in Zone X_UNSHADED, should pay particular attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
27 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Washington County, Iowa has recorded 61 flood-related events since 1996 according to NOAA's Storm Events Database, including 29 flash floods and 32 river or area floods. The county has received 15 federal disaster declarations, 4 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1965–2020)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms | Severe Storm | Aug 10, 2020 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Severe Storm | Jun 26, 2014 |
| Severe Storms, Flooding, And Tornadoes | Severe Storm | Jun 1, 2010 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 25, 2008 |
| Severe Winter Storm | Severe Ice Storm | Dec 10, 2007 |
| Severe Winter Storms | Severe Storm | Feb 23, 2007 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 19, 2004 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jul 20, 2025 | 0.00K |
| Flood | May 29, 2019 | 0.00K |
| Flash Flood | May 28, 2019 | 0.00K |
| Flood | May 20, 2019 | 0.00K |
| Flood | Mar 14, 2019 | 0.00K |
| Flood | Oct 7, 2018 | 0.00K |
| Flash Flood | Aug 28, 2016 | 50.00K |
| Flood | Dec 15, 2015 | 0.00K |
| Flood | Aug 11, 2015 | 0.00K |
| Flash Flood | Aug 9, 2015 | 0.00K |
Flash Flood — Jul 20, 2025
A decaying mesoscale convective system moved into eastern Iowa during the morning hours of July 20th. These showers and storms produced heavy rain with trained spotters reporting 1 to 3 inches of rain. This lead to flash flooding in parts of Washington, Louisa, and Muscatine Counties.
Flood — May 29, 2019
Extensive flooding occurred late May and into June across eastern Iowa, northwest Illinois, and northeast Missouri. The last half of May was very wet with 5-8 inches of rain falling over the region. This combined with saturated soils, brought many rivers above Moderate to Major flood levels. Many climate sites only saw 3 days of no precipitation from May 16th to May 31st. |The Wapsipinicon, Iow...
Flash Flood — May 28, 2019
A frontal boundary settled across northern Kansas, northern Missouri and central Illinois. This front was the focus area for the development of several rounds of showers and thunderstorms that impacted the region. The first round came through during the morning, and produced mainly torrential rainfall, small hail, brief wind gusts and frequent lightning. |The second round of showers and thunder...
Flood — May 20, 2019
Extensive flooding occurred late May and into June across eastern Iowa, northwest Illinois, and northeast Missouri. The last half of May was very wet with 5-8 inches of rain falling over the region. This combined with saturated soils, brought many rivers above Moderate to Major flood levels. Many climate sites only saw 3 days of no precipitation from May 16th to May 31st. |The Wapsipinicon, Iow...
Flood — Mar 14, 2019
Significant flooding occurred across eastern Iowa during the Spring 2019. Moderate to major flooding was observed on most Iowa tributary rivers due to snowmelt, frozen ground, ice jams, saturated soils, and rainfall from March 9th to 12th.The higher crests occurred on the Skunk, English, Cedar, Wapsipinicon, and Maquoketa Rivers in Iowa. Most of these rivers crested during the 2nd and 3rd wee...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Washington County, Iowa:
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.
Properties in Washington County, Iowa 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.