333 flood insurance claims·$6.3M paid·4 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Grundy County, Illinois. 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.
River flooding and flash flooding from summer thunderstorms dominate the flood history of Grundy County, Illinois, supported by 25 recorded flood events and 17 flash flood events over the last 30 years. Recent impacts include localized flooding along the Kankakee River caused by rapid ice formation in January 2024, as well as torrential rain from slow-moving thunderstorms that produced flash flooding, flooded roads, and damaged bridges across western Grundy County in July 2021.
National Flood Insurance Program records show claims across multiple zones, with the highest concentration occurring in Zone A with 230 claims averaging $25,012 and an average recorded water depth of 7 inches. Zone UNKNOWN recorded 59 claims with an average payout of $9,936 and an average water depth of 2 inches. Zone X recorded 29 claims with an average payout of $30,635 and an average water depth of 4 inches, while Zone X_UNSHADED had 10 claims averaging $16,825 with an average water depth of 3 inches, and Zone X_SHADED recorded 5 claims averaging $17,084 with an average water depth of 16 inches. Homeowners and real estate agents in Zone A and properties near rivers should pay the closest attention to these flood risks.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
6% of Grundy County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
245 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 5 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.
The worst year was 2013, with 61 claims and $2.1M paid, the year of Severe Storms, Straight-line Winds, and Flooding.
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.
12 NOAA storm reports from Grundy County describe what happened, in the words of the forecasters who covered it. Read the Illinois flood stories →
15 federal disaster declarations since 1972, 4 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Straight-line Winds, And Tornadoes | Nov 17, 2013 |
| Severe Storms, Straight-line Winds, And Flooding | Apr 16, 2013 |
| Severe Winter Storm And Snowstorm | Jan 31, 2011 |
| Severe Storms And Flooding | Sep 13, 2008 |
| Severe Storms And Flooding | Aug 20, 2007 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Illinois Winter Snow Storms | Dec 11, 2000 |
| Winter Storm 1/1/99 | Jan 1, 1999 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
42 since 1996: 17 flash floods and 25 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jan 15, 2024 | — |
| Flood | Jul 13, 2021 | — |
| Flood | Jul 12, 2021 | — |
| Flash Flood | Jul 12, 2021 | $300,000 |
| Flood | May 17, 2020 | — |
| Flood | Sep 28, 2019 | — |
| Flash Flood | Sep 27, 2019 | — |
| Flood | May 1, 2019 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jan 15, 2024. Very cold temperatures led to rapid ice formation on rivers. Localized flooding due to ice jams occurred along portions of the Kankakee River.
Flood · Jul 13, 2021. Scattered thunderstorms moved across portions of central Illinois during the afternoon and evening of July 12th. One storm moved very slowly over eastern La Salle and western Grundy Counties. Torrential rain produced flash flooding in these areas with numerous roads flooded and at least four bridges damaged.
Flood · Jul 12, 2021. Scattered thunderstorms moved across portions of central Illinois during the afternoon and evening of July 12th. One storm moved very slowly over eastern La Salle and western Grundy Counties. Torrential rain produced flash flooding in these areas with numerous roads flooded and at least four bridges damaged.
Flash Flood · Jul 12, 2021. Scattered thunderstorms moved across portions of central Illinois during the afternoon and evening of July 12th. One storm moved very slowly over eastern La Salle and western Grundy Counties. Torrential rain produced flash flooding in these areas with numerous roads flooded and at least four bridges damaged.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Grundy 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.