444 flood insurance claims·$3.1M paid·6 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 Alexander 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 overflow along the Mississippi and Ohio rivers dominates the flood risk in Alexander County, where the National Centers for Environmental Information recorded 220 general floods compared to 21 flash flood events over the last thirty years. Recent events illustrate this pattern, such as heavy rainfall in February 2025 that caused moderate flooding near Olmsted and minor flooding near Cairo, and subsequent heavy rainfall in May 2024 that pushed the Lower Ohio, Big Muddy, and Mississippi Rivers to flood stage, impacting low-lying areas near Thebes, Olmsted, and Cairo for up to eight days.
National Flood Insurance Program records show claims concentrated heavily in Zone A, which accounts for 239 claims with an average payout of $14,502 and an average recorded water depth of 6 inches. An additional 181 claims were filed under Zone UNKNOWN, averaging $2,502 with an average water depth of 2 inches. Meanwhile, Zone X properties experienced fewer claims—totaling 12 claims—but recorded a higher average payout of $20,214 and an average recorded water depth of 16 inches.
Properties situated near rivers and low-lying bottomlands, particularly those located within Zone A and Zone X, should pay the closest attention to flood risk given the frequency of river overflow events and historical claim severities.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
5% of Alexander County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
251 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 2011, with 85 claims and $1.6M paid, the year of Severe Storms 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.
83 NOAA storm reports from Alexander County describe what happened, in the words of the forecasters who covered it. Read the Illinois flood stories →
17 federal disaster declarations since 1969, 6 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms And Flooding | Feb 24, 2019 |
| Severe Storms And Flooding | Apr 19, 2011 |
| Severe Winter Storm | Jan 26, 2009 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Storms, Tornadoes, And Flooding | May 6, 2003 |
| Severe Storms, Tornadoes And Flooding | Apr 21, 2002 |
| Severe Storms And Flooding | Mar 1, 1997 |
| Severe Storms And Flooding | May 15, 1995 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
241 since 1996: 21 flash floods and 220 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Feb 16, 2025 | — |
| Flood | Mar 1, 2025 | — |
| Flood | Jul 18, 2024 | — |
| Flood | May 10, 2024 | — |
| Flood | May 9, 2024 | — |
| Flood | Jul 6, 2024 | — |
| Flood | Jul 5, 2024 | — |
| Flood | May 3, 2024 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Feb 16, 2025. Heavy rain (3 to 7) over the lower Ohio and Tennessee Valleys on the 15th resulted in rising water levels on the Ohio River, with moderate flooding near Paducah and Olmsted, and minor flooding near Golconda, Smithland, and Cairo. Minor flooding continued into early March near Olmsted and Cairo.
Flood · Mar 1, 2025. A prolonged flooding event on the Ohio river, that began in the middle of February, continued into March at Shawneetown, Olmsted, and Cairo. Minor flooding of bottomland continued at all three locations. Heavy rainfall in the middle of February was the cause of rising river levels which lowered just below flood stage at all three sites from the afternoon of the 1st to the early morning of the 2nd.
Flood · Jul 18, 2024. Torrential rainfall in Southwest Illinois on July 16th resulted in water levels at Thebes briefly returning to minor flood, with limited impacts to low-lying agricultural areas.
Flood · May 10, 2024. Heavy rainfall in early May, culminating in the May 8th severe weather and flooding event, resulted in rising river levels on the Lower Ohio, Big Muddy, and Mississippi Rivers, with Thebes returning to minor flood and Murphysboro, Olmsted, and Cairo reaching flood stage shortly after. Minor flooding in Southern Illinois around these river sites lasted 5 to 8 days with impacts limited to low-lying areas.
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 Alexander 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.