28 flood insurance claims·$179,800 paid·7 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 Hamilton County, Iowa. 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 from prolonged snowmelt and seasonal systems dominates the flood character of Hamilton County, Iowa, supported by 51 flood events compared to 21 flash flood events over the last 30 years. Historical records illustrate these hazards, such as a prolonged flood event in March 2019 driven by a deep regional snowpack and frozen soils, as well as multiple rounds of heavy rain producing flash flooding in June 2018.
National Flood Insurance Program claims data indicates that properties in designated Zone A face the highest frequency and depth of flood risk, recording 20 claims with an average water depth of 21 inches and an average payout of $8,480. Properties with unknown zones recorded 2 claims with an average water depth of 13 inches and an average payout of $18,337, while Zone X properties experienced 6 claims with an average water depth of 2 inches and an average payout of $8,222. Property owners in Zone A and unmapped or unknown zones should pay the closest attention to flood risk, given their higher recorded water depths and claim frequency.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
Less than 1% of Hamilton County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
20 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 16 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 2010, with 13 claims and $108,500 paid, the year of Severe Storms, Flooding, and Tornadoes.
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.
63 NOAA storm reports from Hamilton County describe what happened, in the words of the forecasters who covered it. Read the Iowa flood stories →
21 federal disaster declarations since 1965, 7 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Tornadoes, And Flooding | May 20, 2024 |
| Severe Storms, Straight-line Winds, And Tornadoes | Dec 15, 2021 |
| Severe Storms And Flooding | Mar 12, 2019 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Jun 6, 2018 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Jun 26, 2014 |
| Severe Storms, Flooding, And Tornadoes | Jun 1, 2010 |
| Severe Storms, Tornadoes, And Flooding | May 25, 2008 |
| Severe Winter Storms | Feb 23, 2007 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
72 since 1996: 21 flash floods and 51 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Mar 13, 2019 | $200,000 |
| Flood | Sep 23, 2018 | $100,000 |
| Flash Flood | Jun 14, 2018 | — |
| Flash Flood | Jun 14, 2018 | $10,000 |
| Flood | Sep 25, 2016 | — |
| Flash Flood | Aug 28, 2015 | $10,000 |
| Flash Flood | Aug 28, 2015 | $25,000 |
| Flash Flood | Aug 28, 2015 | $20,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Mar 13, 2019. Reports from the 13h through the 19th in this entry. ||A relatively deep and widespread snowpack existed across the region during early to mid March. Many areas in central and northern Iowa had around a foot to two feet of snow on the ground, along with many areas in upstream river basins in Minnesota and the Dakotas having similar or deeper snowpacks on the ground. Additionally, with the below normal temperatures…
Flood · Sep 23, 2018. Heavy rainfall continued across portions of central and northern Iowa through mid to late September. This allowed rivers across the area to go back into flood through the latter portion of the month. The West Fork of the Des Moines River remained in flood at the end of September and will be included in the October StormData event as well. The basins impacted by flooding were the Des Moines, Cedar, Winnebago, Shell…
Flash Flood · Jun 14, 2018. After a very brief reprieve from multiple days of activity, another round of storms greeted large parts of central Iowa during the very early morning hours of the 14th, through the rest of the morning, and into the afternoon. Traditional severe weather in the form of hail and damaging winds were sporadic, while heavy rain and flash flooding was the main player. The hail and wind reports were low end severe with ge…
Flood · Sep 25, 2016. Several rivers went into flood across central and northern Iowa due to heavy rains received during the month of September, especially during the middle to latter portion of the month. Two of the rivers, the Iowa River at Tama Highway E49 and the Cedar River at Cedar Falls, remained in flood until early October.
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 Hamilton 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.