Colorado Environment & Hazard Risk
2 counties rated high or very high risk. 46,814 storm events since 1996, #16 among states.
- Expected yearly loss
- $2.17B
- $375 per person
- Storm events since 1996
- 46,814
- Most often hail
- Flood insurance policies
- 11,282
- $90.67M in claims paid
- Superfund sites
- 24
- 262 toxic release facilities
Risk by county
FEMA National Risk Index rating, highest risk first
| County | Overall risk | Top hazard | Flood policies | Flood claims paid |
|---|---|---|---|---|
| Denver County | High | Hail | 765 | $719K |
| Jefferson County | High | Hail | 1,293 | $3.06M |
| El Paso County | Moderate | Winter weather | 1,208 | $6M |
| Arapahoe County | Moderate | Hail | 677 | $1.04M |
| Adams County | Moderate | Hail | 283 | $594K |
| Boulder County | Moderate | Lightning | 2,543 | $50.1M |
| Larimer County | Moderate | Lightning | 794 | $15.15M |
| Weld County | Moderate | Hail | 325 | $5.66M |
| Douglas County | Moderate | Lightning | 311 | $661K |
| Pueblo County | Moderate | Lightning | 106 | $332K |
| Eagle County | Low | Avalanche | 213 | $270K |
| La Plata County | Low | Wildfire | 336 | $1.26M |
| Mesa County | Low | Landslide | 201 | $293K |
| Fremont County | Low | Lightning | 184 | $344K |
| Garfield County | Low | Landslide | 103 | $93.72K |
| Summit County | Low | Avalanche | 145 | $20.32K |
| Logan County | Low | Hail | 173 | $847K |
| Pitkin County | Low | Avalanche | 167 | $236K |
| Morgan County | Low | Hail | 78 | $433K |
| Delta County | Low | Landslide | 32 | $86.06K |
| Chaffee County | Low | Landslide | 75 | $307K |
| Otero County | Low | Lightning | 40 | $1.76M |
| Grand County | Low | Avalanche | 33 | $46.18K |
| Montrose County | Low | Lightning | 75 | $60.13K |
| Prowers County | Low | Drought | 17 | $29.73K |
| Montezuma County | Low | Wildfire | 63 | $19.6K |
| Clear Creek County | Low | Avalanche | 73 | $42.94K |
| Rio Grande County | Low | Landslide | 95 | $14.32K |
| Gunnison County | Low | Landslide | 126 | $86.88K |
| Alamosa County | Very Low | Drought | 40 | $4,195 |
| Teller County | Very Low | Wildfire | 37 | $12.02K |
| Rio Blanco County | Very Low | Landslide | 15 | $31.03K |
| Yuma County | Very Low | Hail | 9 | $140K |
| Elbert County | Very Low | Wildfire | 17 | - |
| Broomfield County | Very Low | Hail | 75 | $179K |
| Archuleta County | Very Low | Wildfire | 77 | $123K |
| Routt County | Very Low | Landslide | 151 | $415K |
| Kit Carson County | Very Low | Hail | - | - |
| Huerfano County | Very Low | Wildfire | 34 | $1,116 |
| Las Animas County | Very Low | Wildfire | 7 | $10.99K |
| Baca County | Very Low | Drought | - | - |
| Conejos County | Very Low | Avalanche | 10 | - |
| Park County | Very Low | Wildfire | 25 | $343 |
| San Miguel County | Very Low | Avalanche | 147 | $133K |
| Ouray County | Very Low | Landslide | 24 | $33.73K |
| Saguache County | Very Low | Landslide | 2 | $5,442 |
| Phillips County | Very Low | Drought | 5 | $7,402 |
| Moffat County | Very Low | Landslide | 20 | - |
| Washington County | Very Low | Hail | 1 | - |
| Jackson County | Very Low | Avalanche | - | - |
| Dolores County | Very Low | Landslide | 4 | - |
| San Juan County | Very Low | Avalanche | 2 | $1,144 |
| Lincoln County | Very Low | Hail | 5 | $4,362 |
| Costilla County | Very Low | Landslide | 10 | $10.32K |
| Sedgwick County | Very Low | Drought | 1 | - |
| Gilpin County | Very Low | Wildfire | 11 | $1,462 |
| Lake County | Very Low | Landslide | 8 | $2,582 |
| Bent County | Very Low | Drought | 2 | - |
| Mineral County | Very Low | Avalanche | - | - |
| Custer County | Very Low | Landslide | - | $769 |
| Crowley County | Very Low | Wildfire | - | - |
| Kiowa County | Very Low | Drought | - | - |
| Cheyenne County | Very Low | Drought | - | - |
| Hinsdale County | Very Low | Landslide | 9 | - |
Costliest hazards
Expected annual loss in Colorado, all counties combined
- Hail$341M/yr · 11 counties high
- Wildfire$211M/yr · 5 counties high
- Tornado$188M/yr · 9 counties high
- Cold wave$129M/yr · 6 counties high
- Avalanche$95.62M/yr · 23 counties high
- Lightning$85.11M/yr · 24 counties high
- Strong wind$44.28M/yr · 10 counties high
- Earthquake$41.39M/yr
- Drought$21.94M/yr · 4 counties high
- Winter weather$20.54M/yr · 10 counties high
Storm events by type
Since 1996: 319 deaths, $10.85B in property and crop damage
- Hail13,055
- Winter Weather5,859 · 13 deaths
- Winter Storm5,496 · 4 deaths
- High Wind4,182 · 11 deaths
- Thunderstorm Wind3,792 · 14 deaths
- Heavy Snow3,215 · 4 deaths
- Drought3,045
- Flash Flood1,562 · 29 deaths
- Tornado1,352 · 3 deaths
- Heavy Rain792 · 2 deaths
- Wildfire668 · 15 deaths
- Frost/Freeze611
Events per year
Most damaging storms
Since 2017, ranked by deaths, injuries and damage
- Hail2.75" hail05/08/2017
Edgewater, Jefferson County
$2.3B damage
What happened
The estimated damage is for the entire episode.
- Wildfire12/30/2021
Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County
2 deaths, 6 injured, $2B damage
What happened
Marshall Fire devastated portions of Marshall, Superior and Louisville. Strong downslope winds, with gusts up to 100 mph, fanned a grass fire that originated near the town of Marshall and quickly spread east to Superior and Louisville. The fire was the costliest fire in state history, and residential and business property losses alone were estimated to be slightly over $2 Billion. In all, 1,094 homes were destroyed and 266 homes were damaged. In addition, 7 commercial properties were destroyed and 30 others sustained damage. Tens of thousands fled the fire. Two people died in the fire, while six others were injured.
- Ice Storm01/09/2017
Grand Valley
500 injured
What happened
Freezing rain, up to a half inch thick, quickly accumulated on roads and other surfaces at the beginning of the morning commute. There were hundreds of vehicle accidents and many roads were closed due to crashed vehicles blocking those roads. There were numerous injuries to those who slipped and fell. In fact, emergency rooms at hospitals in the Grand Valley exceeded their daily admittance records with over 200 people treated for broken bones and other blunt force injuries. Schools were closed throughout the Grand Valley, and many businesses were negatively impacted by either not opening, opening late, or the lack of customers.
- Hail3" hail06/19/2018
Englewood, Arapahoe County
$276M damage
What happened
The property estimate value was the total storm damage summary for the event.
- Wildfire10/14/2020
Grand & Summit Counties Below 9000 Feet
2 deaths, $167M damage
What happened
The East Troublesome Fire destroyed 555 structures. Two fatalities were confirmed. Nine buildings suffered major damage and 34 sustained minor damage. Among the buildings destroyed, 366 were residential and 189 were outbuildings. Ten buildings belonging to businesses were destroyed in the fire. Grand County estimated that debris removal could exceed over 30,000 cubic yards and cost more than $27 million to haul off. The property damage estimate only includes the destroyed residences and outbuildings.
- Hail2.75" hail08/06/2018
Colorado Spgs, El Paso County
8 injured, $173M damage
What happened
Eight persons were transported to the hospital from the Cheyenne Mountain Zoo. Time and hail estimated.
Flood insurance
National Flood Insurance Program policies and claims
11,282 homes in Colorado have flood insurance, about 0.6% of residential buildings. In high-risk flood zones, 5,417 of 22,669 homes (24%) are insured.
- Late summer storms$69.59M · 2,155 claims
- Flooding$728K · 113 claims
- Colorado Burn Scar Flash Flooding$270K · 3 claims
Drinking water
1,058 community water systems serve about 7,195,786 people
Since 2021, 269 systems reported 1,572 health-based violations. 185 systems had a violation of any kind still open at last report. These had the most:
- May Valley WaServes 1,500 · Groundwater · Private193 health violations+30 monitoring or reporting
- Valley WcServes 270 · Groundwater · Private74 health violations+22 monitoring or reporting
- South Swink Water AuthorityServes 622 · Groundwater · Local government60 health violations
- Beehive Water AssociationServes 154 · Groundwater · Private51 health violations+38 monitoring or reporting
- Patterson Valley WcServes 96 · Groundwater · Private44 health violations+11 monitoring or reporting
- Eureka WcServes 498 · Groundwater · Private43 health violations+90 monitoring or reporting
- Manzanola Town ofServes 497 · Groundwater · Local government33 health violations+13 monitoring or reporting
- Fayette WcServes 75 · Groundwater · Private33 health violations+17 monitoring or reporting
Select a county above to see every system that serves it.
Climate in the largest cities
1991-2020 normals from the nearest NOAA weather station
| City | July high | Jan low | Rain | Snow |
|---|---|---|---|---|
| Denver | 91°F | 21°F | 15.9 in | 40.7 in |
| Colorado Springs | 81°F | 16°F | - | - |
| Aurora | 90°F | 17°F | - | - |
| Fort Collins | 87°F | 18°F | 15.9 in | 51.4 in |
| Lakewood | 86°F | 21°F | 17.5 in | 58.0 in |
| Thornton | 91°F | 19°F | 14.5 in | 44.8 in |
| Arvada | 88°F | 17°F | 17.1 in | 75.5 in |
| Pueblo | 92°F | 18°F | 12.6 in | 14.8 in |
Pollution sites
24 Superfund sites and 262 toxic release facilities
Superfund sites
- Air Force Plant PjksFinal NPL Site, Littleton
- Bonita Peak Mining DistrictFinal NPL Site, Unincorporated
- Broderick Wood ProductsFinal NPL Site, Denver
- California GulchFinal NPL Site, Leadville
- Captain Jack MillFinal NPL Site, Ward
- Central City, Clear CreekFinal NPL Site, Idaho Springs
- Chemical Sales co.Final NPL Site, Denver
- Colorado SmelterFinal NPL Site, Pueblo
Largest toxic releases
- Cripple Creek & Victor Gold Mining Co7.9 million lbs, Victor
- Climax Molybdenum Co-Henderson Mine4.4 million lbs, Empire
- Climax Molybdenum Co-Climax Mine3.1 million lbs, Climax
- Climax Molybdenum Co Henderson Mill1.7 million lbs, Parshall
- Colorado Springs Utilities Martin Drake Power Plant1.3 million lbs, Colorado Springs
- Clean Harbors Deer Trail LLC.1.1 million lbs, Deer Trail
- Public Service Co of Colorado Comanche Station1.1 million lbs, Pueblo
- Public Service Co of Colorado Hayden Station773,086 lbs, Hayden
Facilities in Colorado reported 28.0 million lbs of toxic releases in 2024, 1.9 million lbs of it into the air.
Frequently asked questions
- What is the biggest natural hazard in Colorado?
- By expected annual loss, hail costs the most in Colorado ($341M a year), according to FEMA's National Risk Index.
- How many storms hit Colorado each year?
- NOAA recorded 46,814 storm events in Colorado since 1996, about 1,510 a year. The most common type is hail.
- How many homes in Colorado have flood insurance?
- 11,282 residential flood insurance policies are in force in Colorado. Since 1978 the National Flood Insurance Program has paid $90.67M on 5,567 claims here.
- How many Superfund sites are in Colorado?
- Colorado has 24 Superfund sites on or deleted from EPA's National Priorities List.
Source: FEMA, NOAA, EPA · Last updated 08/01/2026 · Storm counts include events in forecast zones that touch each county. This product uses the FEMA OpenFEMA API, but is not endorsed by FEMA.