Louisa County, IA Environment & Hazard Risk
Very Low natural hazard risk, led by strong wind. 417 storm events since 1996.
- Expected yearly loss
- $8.45M
- Very Low nationally
- Storm events since 1996
- 417
- Most often thunderstorm wind
- Flood insurance policies
- 97
- 1.6% of homes
- Hurricanes nearby
- 0
- Since 1851
Natural hazard risk
FEMA National Risk Index, December 2025
Overall risk
Very Low
Score 17.5 of 100
Social vulnerability
Very Low
Score 13.6 of 100
Community resilience
Relatively Moderate
Score 58.2 of 100
Community resilience runs the other way: a higher rating means a community can recover faster.
Building value exposed: $3.37B · Agriculture value exposed: $265M · Risk-adjusted yearly loss: $6.92M
Risk by hazard
- Strong windRelatively Moderate$1.52M/yr expected annual loss, about 6.3 events a year
- DroughtRelatively Moderate$1M/yr expected annual loss, about 9.9 events a year
- HailRelatively Low$648K/yr expected annual loss, about 4.4 events a year
- LandslideRelatively Low$4,783/yr expected annual loss, about once every 10 years
- Heat waveRelatively Low$532K/yr expected annual loss, about 8.2 events a year
- Ice stormRelatively Low$105K/yr expected annual loss, about once every 2 years
- WildfireVery Low$24.79K/yr expected annual loss, about once every 1,044 years
- TornadoRelatively Low$828K/yr expected annual loss, about once every 3 years
- EarthquakeVery Low$98.99K/yr expected annual loss, about once every 853 years
- LightningRelatively Low$138K/yr expected annual loss, about 45 events a year
- Winter weatherVery Low$25.59K/yr expected annual loss, about 14 events a year
- Cold waveVery Low$293K/yr expected annual loss, about 5.3 events a year
- HurricaneVery Low$3,288/yr expected annual loss, about once every 128 years
Bars show the national percentile score (0 to 100) for each hazard. Dollar figures are expected annual losses to buildings, people and crops. Not rated here: avalanche, coastal flooding, riverine flooding, tsunami, volcanic activity.
Flood risk and insurance
National Flood Insurance Program and FEMA flood maps
Check the flood zone for an address
- Homes with flood insurance
- 97 of 6,237 (1.6%)
- Homes in high-risk flood zones
- 490
- Insured in high-risk zones
- 43 (9%)
- Flood claims since 1978
- 120
- Claims paid since 1978
- $4.48M
Flood claims paid per year
- Midwest Flooding$270K · 21 claims
- Storm$69.86K · 2 claims
- Flooding$15.87K · 3 claims
- Severe flooding$13.98K · 3 claims
Storm history
Since 1996: 417 events, 5 deaths, $64.75M in damage
- Thunderstorm Wind63 · 1 death
- Flood57
- Hail56
- Winter Storm53
- Winter Weather49 · 3 deaths
- Flash Flood28 · 1 death
- Heavy Snow18
- Drought17
- Dense Fog11
- Ice Storm10
Events per year
16 tornadoes on record (EF0 1, EF1 1, EF2 1, EF3 1, F0 5, F1 2, F2 4).
Most damaging storms
Since 1996, ranked by deaths, injuries and damage
- Winter Weather02/03/2008
Louisa
2 deaths, 1 injured
What happened
Snowfall amounts of 4 to 5 inches were noted across the county. According to the Muscatine Journal, snow played a role in a fatal accident in northern Louisa county near Fredonia on snow-covered county road G40. Two indirect fatalites to children occurred in the accident, ages 9 and 11.
- Flood06/01/2008
Gladwin, Louisa County
$19M damage
What happened
The record crest on the Iowa River at Columbus Junction occurred on June 16, 2008 at 32.49 feet. Flood stage is 19 feet. The record crest on the Iowa River at Wapello occurred on June 14, 2008 at 32.15 feet. Flood stage is 20 feet.
- Drought08/01/2003
Louisa
$14.88M damage
What happened
Dry conditions that began in September 2002 and continued through 2003, manifested into a moderate to severe drought at the start of August 2003 which is a crucial time for soybean development and corn in filling out the ears with large kernels. The last significant widespread rainfall in Eastern Iowa occurred on July 20th with general rainfalls of around an inch. According to data from the Iowa State Climatologist, August 2003 was the driest on record with an statewide average of only 0.96 inches of rainfall, which was 3.23 inches below the normal for August. Hot and humid conditions arrived for the second half of August placing extreme stress on crops that were already suffering from a lack of rainfall. Earlier predictions of a near record or record harvest fell by the wayside by late August. Estimates of yield reduction were 10% for the corn crop, or about $85.8 million. Soybean loses were estimated at 30%, or about $226.7 million.
- Thunderstorm Wind70 kt wind06/29/1998
Countywide, Louisa County
1 death, 1 injured, $1M damage
What happened
Supercell thunderstorms developed over Central Iowa and rapidly intensified into a long squall line which raced southeast over Eastern Iowa into Central Illinois. Numerous funnel clouds were sited along the leading edge of the storm and a few non-supercell tornadoes were masked within a large area of damaging winds. Straightline winds from 60 to over 120 mph produced the most serious damage with these storms and 8 counties in Eastern Iowa were declaired disaster areas. School-net stations measured winds at 69 mph in Cedar Rapids and 123 mph at Washington. Across the county warning area sustained winds of 70 to 80 mph ripped down trees, power lines, and windmills, and knocked over farm buildings, grain bins and silos. One barn in Benton County housing a cargo van and thousands of dollars worth of antiques was blown on it's side. At another property 40 pine trees standing 30 feet high were snapped off. Widespread crop damage was also reported as the winds snapped off brittle corn stalks. Three large Co-operative grain bins in Belle Plaine (Benton County) and two more at Lost Nation and Clarence (Clinton County) were destroyed, and at Wapello (Louisa County) a half...
- Flash Flood06/14/2008
Oakville, Louisa County
1 death
What happened
Major to record flooding caused a levee to fail on the Iowa River at Oakville leading to flash flooding in much of the town. One indirect fatality occurred in rural Oakville in Louisa County. A 35 year old male drowned while attempting to swim across flood waters. He left his car parked with his keys and wallet on one side, and tried to swim across to his home to gather more belongings. He was reported missing on June 14, 2008. A relative told local officials they had warned him not to enter the flood waters, but he replied that he had done it in the flood of 1993. It was concluded by officials that this was not an accidental flood related death.
- Winter Weather12/03/2008
Louisa
1 death
What happened
An indirect fatality occurred in extreme southern Louisa county on U.S. Highway 61 just north of Iowa Highway 78 at about 232 pm CST. An SUV collided with a semi on the snow and ice covered road, killing the SUV driver.
Latest storm reports
Newest first
- Flash Flood06/17/2026
Letts, Louisa County
- Thunderstorm Wind52 kt wind04/17/2026
Wapello, Louisa County
- Thunderstorm Wind56 kt wind04/16/2026
Letts, Louisa County
- Thunderstorm Wind56 kt wind04/16/2026
Fredonia, Louisa County
- Hail1" hail03/31/2026
Grandview, Louisa County
- Hail1.5" hail03/31/2026
Columbus City, Louisa County
- Hail1.75" hail03/31/2026
Letts, Louisa County
- Blizzard03/16/2026
Louisa
Drinking water
8 community water systems serve about 5,760 people. Violations since 2021.
None of the systems serving this county had a health-based violation in this period.
- Wapello Municipal Water WorksServes 1,977 · Groundwater · Local governmentNo health violations
- Columbus Junction Water SupplyServes 1,830 · Groundwater · Local governmentNo health violations+3 monitoring or reporting
- Morning Sun Water DepartmentServes 752 · Groundwater · Local governmentNo health violations
- Grandview Muni Water DeptServes 437 · Groundwater · Local governmentNo health violations+2 monitoring or reporting
- Columbus City Public Water SupplyServes 392 · Purchased groundwater · Local governmentNo health violations+2 monitoring or reporting
- Oakville Water SupplyServes 200 · Groundwater · Local governmentNo health violations+3 monitoring or reporting
- Woodland Wapello Mobile Home ParkServes 126 · Groundwater · PrivateNo health violations+1 monitoring or reporting
- Louisa Co Law Enforcement CtrServes 46 · Groundwater · Local governmentNo health violations+2 monitoring or reporting
Largest systems by population served. Monitoring and reporting violations mean required tests or notices were late or missing, not that the water was unsafe.
Climate
1991-2020 normals at Columbus Junction, 3.6 mi from the county center
Summer highs peak around 84°F in Jul and winter lows bottom out near 11°F in Jan. About 38.8 inches of rain falls in a typical year, with 31.3 inches of snow.
| Month | High | Low | Rain | Snow |
|---|---|---|---|---|
| Jan | 30°F | 11°F | 1.17 in | 9.5 in |
| Feb | 34°F | 14°F | 1.94 in | 7.1 in |
| Mar | 48°F | 26°F | 2.33 in | 5.3 in |
| Apr | 62°F | 38°F | 3.85 in | 1.6 in |
| May | 72°F | 50°F | 5.41 in | - |
| Jun | 80°F | 59°F | 4.91 in | - |
| Jul | 84°F | 63°F | 4.09 in | - |
| Aug | 82°F | 61°F | 4.22 in | - |
| Sep | 76°F | 52°F | 3.75 in | - |
| Oct | 63°F | 40°F | 3.03 in | 0.2 in |
| Nov | 48°F | 27°F | 2.19 in | 1.3 in |
| Dec | 35°F | 17°F | 1.94 in | 6.3 in |
| Year | 49°F average | 38.8 in | 31.3 in | |
Pollution sites
0 Superfund sites and 3 toxic release facilities in Louisa County
Superfund sites
None in this county.
Toxic release facilities
- Tyson Fresh Meats Inc-Louisa County1.6 million lbs released, Columbus Junction
- Midamerican Energy-Louisa Generating Station265,693 lbs released, Muscatine
- Trioak Foods LLC - Feed Mill0 lbs released, Oakville
Total: 1.9 million lbs in 2024, 58,426 lbs to air.
Superfund sitesToxic release facilitiesEPA inspections and enforcementAir toxics cancer risk5 historic places
Frequently asked questions
- How risky is Louisa County for natural disasters?
- FEMA rates Louisa County very low for overall natural hazard risk, with expected losses of $8.45M a year. The highest-rated hazards are strong wind (relatively moderate), drought (relatively moderate), hail (relatively low).
- What storms are most common in Louisa County?
- Since 1996, NOAA recorded 417 storm events affecting Louisa County, most often thunderstorm wind (63), flood (57), hail (56).
- How many tornadoes have hit Louisa County?
- 16 tornadoes have been recorded in Louisa County since 1950, including 1 rated F3/EF3 or stronger.
- How many homes in Louisa County have flood insurance?
- 97 residential flood insurance policies are in force in Louisa County, covering about 1.6% of homes. The program has paid $4.48M on 120 claims here since 1978.
- What is the weather like in Louisa County?
- At Columbus Junction, average highs reach 84°F in Jul and lows fall to 11°F in Jan, with 38.8 inches of rain a year (1991-2020 normals).
Source: FEMA (National Risk Index, NFIP), NOAA (Storm Events, HURDAT2, Climate Normals), EPA · Last updated 08/01/2026 · Storm counts include events in forecast zones that touch the county. This product uses the FEMA OpenFEMA API, but is not endorsed by FEMA.