The 2002 fire season was one of the biggest of the past half-century. By the end of the year, fires had burned across 7.2 million acres, costing over $1 billion to fight. Almost uniformly, the fires of 2002 were characterized as catastrophic, but in fact, each fire was unique in character, offering individual lessons for the future. The following fact sheet is one of five analyses prepared by The Wilderness Society to better understand the causes and consequences of major 2002 wildfires.
Quick Facts
Location: Pike-San Isabel National Forest, 30 miles southwest of Denver, Colorado. Cause: Human (arson).
Area within fire perimeter: 137,760 acres. Structures lost: 133 homes, 1 commercial building and 466 outbuildings. Ownership: 72% National Forest. Landscape: Rugged terrain with Ponderosa Pine, Mixed Conifer, Gambel oak and Aspen. Suppression Cost: $39.9 million approximately. |
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Beginning in a campfire circle on the morning of June 8, 2002, the Hayman fire would quickly grow to become the largest recorded wildfire in Colorado's history. Spurred by record drought and extreme weather, the Hayman fire would burn nearly 138,000 acres over the course of three weeks. Two major fire activity periods, June 8-10 and June 17-18, marked by high winds and record-low relative humidity, would account for the majority of the total acreage burned as well as 93% of the 132 homes lost.
Severe drought was a significant factor
By the first week of June, all of Colorado was experiencing severe to extreme drought conditions. Snowpack throughout the spring was at less than 50 percent of normal with melt-out occurring almost six weeks ahead of the usual date. Fuel moisture in the Hayman area was at record lows and was seen as approaching the "theoretical lower limit." 1
Extreme weather conditions promoted rapid spread
On June 9, 2002, the National Interagency Fire Center issued a Red Flag Warning in Colorado for winds at 25-35 mph, very warm weather and extremely low relative humidity. News outlets reported gusts of up to 60 mph. On this Red Flag day, the Hayman fire ran for 17 miles, burned through a series of small fuel reduction projects, at least one clearcut, and across many roads including a 3-lane highway. Indicative of the extreme conditions, one section of the fire spread ½ mile in just four minutes. "This fire is totally dominated by mother nature, all wind-driven and because of the drought conditions it's that much more unpredictable," said Susan Haywood, spokeswoman for an interagency firefighting team.2
Only previous fires and changing weather slowed the Hayman fire
Over 21,000 acres of modified fuels (previous wildfires, prescribed burning, thinning, logging, etc.) were encountered by the Hayman fire. Forest Service researchers and university scientists who reviewed the fire determined that the fire's response to these fuel modifications was complex and does not lend itself to any one conclusion or summary.3 On moderate weather days, instances of both success and failure in terms of altering the fire's spread or severity were observed. Aided by high winds on extreme weather days, however, the fire burned through fuel treatments unaffected. Significantly, the only fuel modification deemed to have "stopped" the fire was recent fire (rather than thinning).
Much of the land within the Hayman Fire Boundary did not burn and less than one-third of the area burned severely
Even the largest and most intense fires burn in what is referred to as a mosaic pattern. Depending on a host of factors -- weather, winds, relative humidity, fuel type, forest density and slope -- fires burn with varying intensity killing virtually all trees in some patches while leaving other patches untouched. While the area within the burn perimeter of the Hayman Fire was close to 138,000 acres, almost half of the area (over 66,000 acres) either did not burn, or burned in a beneficial low intensity fashion.
According to the Hayman Fire Burned Area Emergency Stabilization and Rehabilitation (BAER) Report, 44,000 acres (32% of total) burned at high severity (Map 14), most of the acres occurring on one day, June 9th (Map 2,4 arrows), when high winds and record temperatures made control impossible.
For More Information
Footnotes
- Interim Hayman Fire Case Study Analysis (Interim Draft), USFS Rocky Mountain Research Station, Nov. 13, 2002.
- The Denver Post, "Fire threatens Denver suburbs," Monday, June 10, 2002
- Interim Hayman Fire Case Study Analysis (Interim Draft), USFS Rocky Mountain Research Station, Nov. 13, 2002.
- BAER Report, Hayman Fire, 5 July 2002, http://wildfires.nwcg.gov/colorado/hayman/baer/hayman_fire_BAER_final.htm
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