Hazard Analysis

As the population of Fort Collins increases, so does the threat to its inhabitants from the dangerous natural phenomena which occur here. Add to this the threat from man-made disasters resulting from nothing more than the increasing population, and a picture begins to form of our level of disaster vulnerability.

Fort Collins is experiencing a period of incredible growth. In 1970 the population of Fort Collins was 43,000. The population estimate in 1999 was 110,000 and current trends indicate this figure may double by the year 2010. At the time of the 1990 census, 30% of the city's population was either under 19 or over 64 years of age. This is significant because certain segments of the population, namely the elderly and the very young, are statistically the most vulnerable to the effects of catastrophic events.

Historically, from its very beginnings as 'Camp Collins' during the Civil War era, our community has suffered the effects of the violent weather which is commonplace here. In 1864 Camp Collins was inundated by a flash flood which destroyed the settlement and carried it away under a twenty foot wall of water traveling at 30 miles per hour. The settlement was relocated to a spot near present day 'Old Town' and was rebuilt. The new settlement, re-named Fort Collins, flourished despite the occasional catastrophe, and continues to do so today. It is this community pride and determination which has become the hallmark of Fort Collins and continues to evidence itself with each new challenge we face.

Click on the sidebar items on the left for a summary of those hazards from which, based on our analysis, the citizens of the City of Fort Collins are most vulnerable.

Hazard: Flooding

Fort Collins has a well documented history of notable floods, beginning with the flood of June 9, 1864, described earlier in this document. The city has experienced other notable floods in 1891, 1902, 1904, 1924, 1938, 1951, 1977, and the well known Spring Creek flood of July 28, 1997 which is mentioned in greater detail below.

The most recent flooding to affect Fort Collins occurred on the Poudre River on April 30, 1999. A slow-moving spring storm brought rain and melted winter snowpack, swelling the river and causing general flooding throughout the city. Even though this was classified as a 'ten year flood,' the resulting damage was greatly minimized by aggressive floodplain management, and proactive emergency response and coordination.

Fort Collins has experienced urban flash flooding as a result of intense local rainfall occurring in a short period of time. While not all of these events are historically significant, many have caused serious property damage. The Old Town Drainage Basin is quite vulnerable to this type of flooding, as evidenced in 1992 when a short, intense rainfall caused approximately $450,000 worth of property damage.

Several floods occurred on Spring Creek prior to the completion of Horsetooth Reservoir. Completed in the early 1950's, Horsetooth Reservoir now cuts off the upper portion of the Spring Creek Drainage Basin, helping to mitigate flooding. However, in July of 1997 Fort Collins experienced a devastating flood on Spring Creek resulting in the loss of five lives. The flood was the result of a very heavy, slow moving thunderstorm which saturated the ground over a two day period and dropped a total of 14½ inches of rain near the mouth of Spring Creek. This was the second largest flood in Colorado history. Property damage totaled over $200 million.

Hazard: Winter Storms

Northern Colorado commonly experiences several winter storms each year, including blizzards, heavy snows and freezing rain. While the citizens of the city of Fort Collins are not as isolated as those people living in outlying areas, they are still vulnerable to the extreme conditions caused by winter storms.

Heavy snow can immobilize a region and paralyze a city, stranding motorists, stopping the flow of supplies, and disrupting emergency and medical services. Accumulations of snow can collapse buildings and knock down trees and power lines. The resulting danger to the community from utility outages can become critical, particularly to the elderly or the very young. The cost of snow removal, repairing damages, and loss of business can have a huge economic impact on cities and towns.

These winter storms are often called deceptive killers because many of the deaths that occur are indirectly related to the storm. For example, many victims of winter storms die in traffic accidents on icy roads, or they die of heart attacks while shoveling snow. Some die of hypothermia from prolonged exposure to cold.

Hazard: Severe Thunderstorms

Thunderstorms affect relatively small areas when compared with hurricanes and winter storms. The typical thunderstorm is 15 miles in diameter and lasts an average of 30 minutes. Despite their small size, all thunderstorms are dangerous. Every thunderstorm produces lightning, which kills more people each year than tornadoes. Heavy rain from thunderstorms can lead to flash flooding. Strong winds, hail, and tornadoes are also dangers associated with severe thunderstorms.

Hail, a frequent product of severe thunderstorms, causes nearly $1 billion in damage to property and crops each year nationwide. The costliest U.S. hailstorm ever was in Denver, Colorado on July 11, 1990. The total hail damage from this single storm was estimated at $625 million. Property damage estimates from hail in Colorado frequently top $50 million a year. Hail in Colorado is an unavoidable part of life. In fact, most years Colorado earns the title of 'hail capital' of the United States.

Hazard: Dam Failures

In the State of Colorado 228 dams have been categorized by the State Engineer as "high hazard," meaning that if the dam were to fail, no matter how remote the possibility, there would be significant loss of life. Due to the dense downstream population of Fort Collins, all four dams at Horsetooth Reservoir (located just west and upstream from the city) are in the "high hazard" category. These dams are subject to daily inspections by Bureau of Reclamation personnel, and an Emergency Notification Procedure is in place should a dam failure or major release of water occur.

There are, in addition, 107 smaller dams in and around Fort Collins. In general, the greatest hazard associated with dams in Colorado is related to seismic activity. There is a possibility that an earthquake (or minor seismic activity) could shake the foundation of a dam, causing the structure to weaken and fail. This along with the possibility of flash flooding intensifies the degree of risk. Our seismic risk is considered in greater detail in the "Hazard: Earthquakes" section below.

Hazard: Earthquakes

There are more than 200 known, potentially active faults within Colorado's complex geological structures. In addition to known faults, seismograph instruments have recorded seismic activity in other areas of Colorado where earthquakes have been felt, but where faults were not visible to geologists. Interestingly enough, the largest earthquake in Colorado history took place on November 7, 1882 and the epicenter was described as "west of Fort Collins." This was also the first recorded earthquake to cause damage in Denver. Based upon accounts at the time it is now estimated to have been the equivalent of a magnitude 6.6 on the Richter Scale. The fact that such a severe seismic event happened so near Fort Collins requires us to consider the possibility that a similar earthquake, or even a more severe one is not beyond the realm of possibility. A quake of such magnitude occurring in Fort Collins today would be a catastrophic event.

Many of Colorado's lifelines, such as power and other utility lines, are at risk from earthquakes. In addition, infrastructure, special facilities, and critical facilities are also at risk. Earthquake ground shaking and related ground failure hazards can contribute to damage or failure of dams, bridges, utilities, and other structures. The earthquake damage to these facilities can cause even further loss of life and damage. For instance, flooding can occur after a dam failure and fire can result from damage to a natural gas pipeline. Hazardous, toxic substances can be released after earthquakes causing damage to buildings or other facilities and contaminating the ground water.

In addition, a variety of dangerous secondary events can happen simultaneously. The ground shaking from earthquakes can cause landslides, rockfall, debris flow, subsidence, soil liquefaction, or even snow avalanches. These ground failure-related hazards triggered by the ground shaking from earthquakes can contribute to additional loss of life and property losses. When soil liquefies it loses its bearing capacity and is unable to support buildings. The buildings on it tilt or collapse, causing additional losses.

Hazard: Tornadoes

Although tornadoes occur in many parts of the world, these destructive forces of nature are found most frequently in the United States east of the Rocky Mountains during the spring and summer months. In an average year, 800 tornadoes are reported nationwide, resulting in 80 deaths and over 1,500 injuries. The most violent tornadoes are capable of tremendous destruction with wind speeds of 250 mph or more. Damage paths can be in excess of one mile wide and 50 miles long.

Historical data confirms that cities along the foothills of the Front Range can expect a significant number of tornadoes each year, particularly during the spring and summer months. While no tornado has ever struck within the city limits of Fort Collins, it is likely this will eventually occur. Tornadoes are historically the most destructive of all atmospheric-generated happenings and as such are a significant hazard. With timely notification of tornado watches and warnings by the National Weather Service, expeditious dissemination of those warnings by emergency management and response organizations, and prior knowledge of protective measures that should be taken by the affected populace, considerable savings in human life can be achieved despite the ferocity and unpredictability of these storms.

More Information

Hazard: Fires

The potential for a large scale, disastrous fire exists in some areas of Fort Collins. The "Old Town" portion of the city consists of many turn-of-the-century heavy timber and masonry buildings. While quite a few of these buildings have been renovated, there are still areas in need of restoration. Another concern is that of the urban wildland interface. More and more, large estates are being built in the foothills area, and thus are vulnerable to the threat of wildfires. Finally, a new style of residential development features large homes and townhouses built in high density neighborhoods. These areas have less access and more combustible construction methods.

None of the above conditions would be an extreme threat were it not for Fort Collins' weather patterns. In addition to frequent winds of 30-40 mph in the spring and fall, wind storms with gusts up to 100 mph occur several times a year.

Many fires in the western United States are started by lightning. In the past decade over 15,000 lightning-induced fires nationwide have resulted in several hundred million dollars a year in damage and the loss of 2 million acres of forest.

Hazard: Hazardous Materials Spills or Releases

Large quantities of hazardous materials, such as chemicals and pesticides of varying complexity and toxicity, and nuclear waste are being manufactured, stored, and/or transported within and across Colorado. A serious problem in the City of Fort Collins is the increasing probability that a hazardous materials spill will occur along a transportation route, particularly Interstate 25, Highway 14, or the Burlington Northern and Union Pacific Railroads.

Interstate 25, which runs north and south along the eastern boundaries of the City of Fort Collins, has been designated as a Hazardous and Nuclear Materials Transportation Route by the Colorado Department of Highways. It is used as a route to the WIPP facility in New Mexico where nuclear waste is stored. The population along this corridor is increasing as Fort Collins spreads eastward.

On a national level, it has been estimated that 35% of all freight trains carry hazardous materials, but that only 7.5% of railroad accidents involve trains carrying these materials. This rate is attributed to safety regulations by the railroad industry and the federal government. The railroad tracks crossing the city, however, intersect and are in close proximity to densely populated areas, and as such the threat of a serious rail accident is of great concern. The tracks are used heavily on a daily basis.

Hazardous and radioactive materials transport by motor vehicle is prohibited by ordinance within the city limits of Fort Collins except for the purpose of making pickups and/or deliveries within the city. There area a number of fixed facilities within the city limits which store hazardous and toxic chemicals and which are subject to deliveries and disposal of hazardous waste. A serious transportation accident involving these materials and the subsequent chemical spill could endanger a substantial number of citizens.

The United States Environmental Protection Agency (EPA) requires any facility with a minimum quantity of certain toxic chemicals to register those chemicals and, in certain cases, create an Emergency Response Plan in the event of accidental release of those chemicals into the environment. Within the city limits of Fort Collins several facilities have such reports on file. In addition, there are many such facilities located on the campus of Colorado State University which, while not within the jurisdiction of the City of Fort Collins, pose a considerable threat to the heavily populated areas of the city which surround the campus.

Hazard: Civil Disturbances/Terrorism

As would be expected of a city its size, Fort Collins also has a history of civil disturbance and some isolated incidents of terrorism directed at visiting dignitaries and individuals from foreign countries. Colorado State University was the site of anti-war demonstrations on May 8, 1970 which resulted in the burning of the historic "Old Main" building on the Colorado State University campus. In 1987 a large party in the Baystone area erupted into a riot. In January 1998 a street riot occurred while people were celebrating the SuperBowl victory of the Denver Broncos football team. Futuristic predictions by law enforcement analysts indicate that urban unrest and civil disorder (of the 1960's - 1970's magnitude) will take place throughout the next decade.

Conclusion:

The City of Fort Collins has experienced significant and regular disasters throughout its history. There is nothing to indicate that the future will be more fortuitous. In fact, the increasing size and population of Fort Collins and surrounding communities indicates just the opposite. In today's world of "cutback" management there are precious few resources available for new programs, particularly those which would require major sources of revenue to fund. It is the challenge of the modern Emergency Manager to find innovative ways to accomplish what must be done to make our communities as safe as they can possibly be.

We feel that our precious resources are best used in endeavors that will mitigate those hazards to which we are most vulnerable, and from which we are most likely to suffer significant losses. To that end, we in the Office of Emergency Management have conducted this risk analysis and have identified those events which we feel pose the greatest hazard to the Fort Collins community in the foreseeable future. We are looking forward to continuing our efforts to educate ourselves and our community about these potential hazards, and doing all that we can possibly do to lessen the impact of future disasters which are certain to come.