Enter any address in Delaware County, Pennsylvania to see its FEMA flood zone
Flash flooding from heavy rainfall is the dominant flood character in Delaware County, PA. Over the past 30 years, NOAA Storm Events data recorded 144 flash flood events, alongside 71 general flood events, 38 coastal flood events, 17 storm surge/tide events, and 3 tropical storms. Recent events include flash flooding on July 9, 2025, attributed to a slow-moving cold front producing heavy rain.
National Flood Insurance Program (NFIP) claims data shows that properties in Zone A have experienced the most claims, with 1644 claims averaging $23,493 and a water depth of 4.4 feet. Zone X also saw significant claims, with 544 claims averaging $13,390 and a water depth of 3.0 feet. Properties in Zone X_SHADED, though fewer in number, had a higher average payout of $14,991 with an average water depth of 4.1 feet.
Homeowners in areas designated as Zone A, Zone X_SHADED, or those located near rivers and coastal areas should pay particular attention to flood risk. Properties without a Base Flood Elevation (BFE) may also face higher risks.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
46 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Delaware County, Pennsylvania has recorded 273 flood-related events since 1996 according to NOAA's Storm Events Database, including 144 flash floods and 71 river or area floods. The county has received 24 federal disaster declarations, 6 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1965–2021)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Remnants Of Hurricane Ida | Hurricane | Aug 31, 2021 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Winter Storm | Severe Ice Storm | Feb 4, 2014 |
| Hurricane Sandy | Hurricane | Oct 26, 2012 |
| Remnants Of Tropical Storm Lee | Flood | Sep 3, 2011 |
| Tropical Storm Lee | Flood | Sep 3, 2011 |
| Hurricane Irene | Hurricane | Aug 26, 2011 |
| Severe Winter Storms And Snowstorms | Snowstorm | Feb 5, 2010 |
| Hurricane Katrina | Hurricane | Aug 29, 2005 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jul 31, 2025 | 0.00K |
| Flash Flood | May 30, 2025 | 0.00K |
| Flash Flood | May 16, 2025 | 10.00K |
| Flash Flood | May 16, 2025 | 15.00K |
| Flash Flood | May 16, 2025 | 20.00K |
| Flash Flood | Jul 9, 2025 | 0.00K |
| Flash Flood | Jul 9, 2025 | 5.00K |
| Flash Flood | Jul 9, 2025 | 25.00K |
| Flash Flood | Jul 9, 2025 | 30.00K |
| Flash Flood | Jul 9, 2025 | 20.00K |
Flash Flood — Jul 31, 2025
A stationary front sparked off showers and thunderstorms across the forecast area. Flash flooding resulted.
Flash Flood — May 30, 2025
Thunderstorms, in the vicinity a cold front, produced flash flooding.
Flash Flood — May 16, 2025
Scattered thunderstorms developed along a slow moving warm front.
Flash Flood — Jul 9, 2025
A slow-moving cold front produced heavy rain and flash flooding across portions of the region. This is the same front that caused flash flooding the day prior.
Flash Flood — Jul 8, 2025
A cold front produced heavy rain and flash flooding across portions of the region.
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 Delaware County, Pennsylvania:
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 Delaware County, Pennsylvania 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.