Cause - Project
between Hwy 67 and the Arizona Trail on the west and the 2000 Outlet Fire history area on the east (AZ)
Park Status - Moderate to heavy smoke impacts to Highway 67 are anticipated throughout the Thompson Rx. Daytime visitors should be prepared for poor visibility as well as possible delays and intermittent closures of the entrance road. Overnight closures of the entrance road are also possible. Additional closures of the Arizona Trail are being implemented in association with the Thompson Rx. (The previous closure associated with the Range Rx remains in effect.) Beginning Friday, November 2, at 8:30 a.m., the Arizona Trail will be closed from Forest Road 610 to the Point Sublime (w1) Road. During daylight hours, public safety officers will continue to check the trail closures approximately once per hour and shuttle hikers to the next available access point as necessary. The Range Road (also known as the w1a road) remains closed at this time.
Status as of 11/02/2012
Acreage - This burn unit is approximately 2,000 acres in size and is composed primarily of ponderosa pine with spruce, fir, and aspen. The Thompson burn unit has not experienced recent fire, resulting in a significant build-up of large dead and down fuels.
Estimated completion date is November 2012.
The Thompson Burn Unit is a narrow burn unit located along the northern boundary of the park between Highway 67 and the Arizona Trail on the west and the 2000 Outlet Fire history area on the east. This burn unit actually extends north of the park boundary to Forest Service road 610. As a result, the Thompson Rx will be managed jointly by the NPS and USFS.
Fire managers plan to begin hand and aerial ignitions on the Thompson prescribed fire unit on Friday, November 2, if environmental conditions are favorable. Ignitions are anticipated to occur over a period of four to five days if fire effects and behavior are favorable. This prescribed burn will be initiated using a combination of aerial and hand ignitions. Like all prescribed fires, the plans for the Thompson Prescribed Fire contain a set of parameters which define (among other things) the expected weather and fuel conditions under which the fire can be initiated. Prior to implementing the burn, fire managers will evaluate current conditions and will only ignite the fires if the prescribed conditions are within those parameters.
ponderosa pine with spruce, fir, and aspen
Moderate to heavy smoke impacts to Highway 67 (the park entrance road) are anticipated throughout the Thompson Rx. Smoke will be most visible during ignition operations and will likely gradually diminish after ignitions are completed. It is expected that smoke will continue to be visible until a major rain or snow event occurs. Smoke will be visible along Highway 67 and Highway 89A as well as from various locations on both the North and South Rims. During the day, smoke is expected to rise as temperatures warm and settle as temperatures cool in the evening. Smoke is also expected to settle into the canyon at night and may also settle in the North Rim development, House Rock Valley, Marble Canyon and Page areas. Smoke impacts have the potential to be heavy in the inner canyon.
Benefits of the burn
Objectives include reducing accumulations of forest fuels, maintaining the natural role of fire in a fire-adapted ecosystem, and protection of sensitive cultural resources, creating a defensible space along the park/forest boundary to aid in protecting threatened and endangered species habitat adjacent to the boundary, including Apache trout and Mexican spotted owl habitat.
US Forest Service
For additional information, visit the Incident Website