Emory Pass/ Sawyer’s Peak
Black Range RD / Gila NF
Emory Pass and Sawyer’s Peak mark one of the most scenic drives in New Mexico. Each year thousands of people make the twisty and steep ascent to travel across the Black Range for pleasure or business. Starting in 2003 an infestation of Western Pine beetle and Fir Engraver beetles resulted in massive mortality of White fir and ponderosa pine in the upper elevations. In 2008 observations by employees of the US Forest Service concluded that the situation was not likely to improve and a concerted effort was made to determine what if anything could be done to lessen the likelihood of a catastrophic fire in the area and the subsequent direct and indirect affects to the communities of Hillsboro, Kingston, and outlying landowners.
The last large fire in modern history to burn in this general area was the McKnight Fire of 1951. The McKnight fire burned over 41,000 acres, primarily west of the divide and lasted for 6-8 weeks. According to some of the people who lived in Kingston at the time….ash rained like snow for days on end, blotting out the sun. Unfortunately records for the McKnight fire are sparse and don’t provide a lot of information, although the scar from the fire is still evident to a practiced eye. The Emory Pass and Sawyer’s Peak areas do not appear to have burned during the McKnight fire.
Mixed conifer typically burns on what is referred to as a 200-year cycle of stand replacement. When these types of forests burn, it is often total and succession starts over. This is in sharp contrast to Ponderosa pine forests which historically burned on a 6-8 year cycle with cool under story burns, hence rarely experience stand replacement events. When considering the Emory Sawyer’s Peak area where in that 200-year cycle are we and what can we expect? Neither is an easy question to answer. We can indirectly estimate from current composition of the vegetation how far into the 200 years we may be. Aspen clones benefit from a stand replacement fire in mixed-conifer. Individual aspen trees rarely live over 150 years, while the clones may persist for centuries. The area has few aspens compared with similar areas in the region suggesting that it has been a long time since the area burned with any intensity.
Climate change and its potential for long term effects on vegetation may result in type conversion of mixed-conifer following large scale fires. Perhaps eliminating them from the mountain for the foreseeable future.
The beetle kill affected area includes portions of two major watersheds, Middle-South Percha Creek and Gallinas Creek.
Middle-South Percha Creek main watershed contains 21,464 acres of which 2,629 (12%) acres exhibit severe beetle kill. Emory Pass is located at an elevation of 8,228 feet, with Sawyer’s Peak to the south reaching 9,668 feet and Cross O Mountain to the north at 9,620 feet. The Black Range Mountains run north to south, with drainages flowing both easterly and westerly. Vegetation at the highest elevations is dominated by mixed conifer, including white fir, Douglas fir, aspen and Gambel oak. As elevations decline, the vegetation transitions to ponderosa pine, then pinyon and juniper, with grey oak and shrub lands occurring at the lower elevations of the watershed.
The principal period of erosive precipitation events occurs during late June through September. During this period, rainfall is characterized by convective high intensity, short duration storms typical of the southwestern monsoon season. Storms are generally of limited extent, averaging five square miles. This period poses the most immediate threat of watershed and downstream damage due to accelerated runoff and erosion. During the latter part of this period and continuing into October, there is also the threat of high intensity, longer duration storms of cyclonic origin associated with Gulf of Mexico and Pacific Ocean hurricanes. These usually do not occur with the same regularity as the monsoons, but can be very damaging. The second mode of a generally bimodal precipitation distribution occurs during the period of November through March when precipitation at the higher elevations falls mainly as snow. Snow pack at this elevation generally develops gradually over this period but melts over a much shorter time span. This runoff produces the largest total yield of the watersheds but generally produces lower peak flows than the monsoon season.
The high intensity monsoon season 25 year, 1 hour, precipitation event is considered the principal risk for watershed damage after a large fire. Such storms for the Emory Pass / Sawyer Peak area produce 1.89 inches (NOAA Atlas 14, 2009) of rainfall.
Geology in the area is characterized by rhyolitic tuffs, andesites, limestones and a small amount of alluvium. Soils can be characterized as variable with moderately deep to deep soils on the northerly facing mixed conifer and pine slopes to shallow on the southerly facing pinyon/juniper or shrub slopes. Soils can be classified into hydrological soil groups A, B, C, and D these groups are based on the soils runoff potential. A majority of the soils found in the watersheds evaluated fall into hydrological soil groups C and D, which have moderately high to high runoff potentials.
The Emory Pass/ Sawyer Peak area drains into the Percha Creek and Upper Mimbres sub-watersheds.
The Middle-South Percha sub-watershed drains to the east with all drainages being tributary to Percha Creek. Ladrone Gulch flows into Middle Percha above Kingston, with cumulative flow from these drainages flowing directly through Kingston. Approximately two miles east of Kingston Middle Percha joins with South Percha to form main stem Percha Creek which flows through Hillsboro. A large portion of the town of Hillsboro is located within the flood plain.
The Upper Mimbres main watershed drains towards the southwest with all drainages tributary to Gallinas Creek. Headwater drainages; Turkey Run Canyon, Railroad Canyon, East Railroad Canyon, Dry Gallinas Canyon, Little Bear Canyon, Iron Creek, Spring Canyon and upper portions of Gallinas Creek) of this main watershed would most likely be negatively impacted by wildfire as mixed conifer and pine are the dominant vegetation types. The entire watershed drains into the Mimbres River downstream of the towns of San Juan and Sherman. Several parcels of private land along Gallinas Creek prior to its confluence with the Mimbres River, including ranch land, homes, roads and other infrastructure, could be at risk during periods of flooding.
Current fuel loading is very high in the majority of the mixed-conifer and pine sites and not nearly as heavy in the pinyon-juniper and shrub lands.
There are no stream gages on any of the main watersheds. Percha Creek within Hillsboro has flooded on several occasions, overtopping flood dikes and damaging buildings, homes, bridges, roads and other infrastructure, even in the absence a wildfire, or other watershed degradation in the uplands
Projected Post-fire effects
Existing knowledge and science related to post fire effects on burned watersheds in the Southwest was reviewed to estimate potential outcomes of wild land fire within the Emory Pass/ Sawyer Peak Area. Forested watersheds with good hydrological conditions (>75% of the ground covered with vegetation and litter) sustain stream base flow conditions for much or all of the year and produce little sediment. Under these conditions, 2% or less rainfall becomes surface runoff and erosion is low.
In areas of light burn intensities with minimal destruction of the duff layer, some increase in runoff is noted, but without drastic alterations in stream flow discharges. In areas of moderate to high severity burn, where all twigs and needles have been consumed, it is reasonable to expect the following situation: a) minimal protection of soil particles to detachment by rain splash and overland flow; b) no needles to moderate surface soil temperatures and facilitate soil moisture storage (which may lead to longer vegetation recovery times); and c) no needles to immediately add organic matter. The lack of needles, combined with a thin but strong water repellant surface layer, will lead to rapid runoff and substantial soil erosion during intense storms. Moderate severity burn areas are expected to respond to future rain events in much the same way as high severity burn areas. When severe fires create poor hydrological conditions (<10% of the ground surface covered with plants and litter), surface runoff can increase over 70% and erosion can increase by 300%.
Wildfires in steep terrain produce the greatest amounts of sediment yield. Erosion on burned areas typically declines over time, decreasing by an order of magnitude in the second year, and in certain case to no sediment by the fourth year. Severely burned areas can decline to background levels within 3 years. Post-fire rehabilitation treatments to reduce erosion in the first years are critical.
Values at Risk
A large wildfire in the Emory Pass/ Sawyer Peak area could have numerous direct and indirect effects. The following list may not be all inclusive:
Private structures (within isolated communities)
• 100+ structures on private land in Hillsboro
• Dikes adjacent to Hillsboro subject to overtopping due to excessive water flow
• 50+ structures on private land in Kingston
• Private inholdings within the watershed near Kingston, Hillsboro, and adjacent drainages
NM State Road System
• NM152 from Kingston to below Hillsboro subject to overtopping and damage by flood flows
• Four bridges crossing Percha Creel at risk of washout on NM152 due to insufficient capacity for estimated flow, inundation by sedimentation, or plugging with debris
• One bridge crossing Mimbres River on NM61 at confluence of Gallinas Creek and Mimbres River due to insufficient capacity for estimated flow, inundation by sedimentation, or plugging by debris
National Forest System Roads
• Several culverts at risk of washout due to insufficient capacity for estimate flow, inundation by sedimentation, or plugging by debris
• Forest roads at risk of breaching if culverts washout
• Forest roads at risk of surface disruption due to excessive flows and sedimentation from adjacent hill slopes
National Forest System Trails
• Erosion of forest due to moderate to high severity fires
National Forest Campgrounds
• Stream crossing and camp units at risk of damage along Gallinas Creek, Iron Creek, and Railroad Canyon due to flooding within these drainages
• Campground at east of Kingston due to flooding Middle Percha Creek
Potential Effects of Fire within the Emory Pass/ Sawyer Peak area
In an effort to quantify the effects of fire three scenarios were proposed; low intensity, moderate intensity and high intensity. No pre or post modeling efforts have been completed at this time. Although modeling efforts would help refine our predictions.
Low Intensity Fire – A low intensity fire would be characterized by primarily ground fire, low flame heights, and minimal consumption of large woody materials. This would result in minor increase in stream flows through the affected watersheds, which would likely be short lived and return to normal within one to two years. There is little probability of increased risk to the towns of Hillsboro and Kingston. Due to its location in Percha creek, Hillsboro is already at high risk of flooding during any peak stream flow event. There is little probability to have debris flows of floatable and transportable material down stream channels. Risks to road crossings, bridges, private property, and channel stability should remain similar to current conditions.
Moderate Intensity and Large Scale Fires – A moderate fire would be characterized by a mix of ground and crown fire, medium flame lengths and general consumption of large woody debris. Large scale is simply a fire covering a majority of the watershed. Moderate and large scale fires are evaluated together as research indicates that these types of fires react in similar ways. Vegetative ground cover will be greatly reduced or eliminated, in much of the moderate to severely burned areas. Reactions to precipitation events will be similar, however the scale would be somewhat reduced under moderate burns. Some areas of high severity burn would likely repel water thereby increasing flows.
Stream flows are likely to increase due to a combination of loss of groundcover, decreased infiltration, a reduction in evapotranspiration, reduced water storage within the soil and possible snowmelt modification at high elevations. Moderate to high severity burn areas in high precipitation zones would produce the largest increase in runoff, even with normal rainfall. The increased risk of flash floods would threaten recreational roads and camp sites, in particular Forest Campgrounds along Gallinas Creek, Railroad canyon, Middle Percha Creek, and Iron Creek. The towns of Kingston and Hillsboro are at a high risk for bank and dike overtopping with water inundation in the 50yr to 100 yr floodplain. Flood flows are anticipated to be several orders of magnitude greater than what would normally be expected following a 25 year, 1 hour rain event. There would be an increased risk to human safety within the channels, floodplains and flood prone areas of the watersheds.
Possible Solutions to Wild Fire Risk
Forest Specialists in Timber, Vegetation Management and Fire were pulled together to determine the feasibility, economics and probable success of treating the beetle kill area and minimizing the potential effects of a wildfire to the national forest and affected communities. White papers were written and are summarized as follows.
Timber Harvest Feasibility
The condition of the dead white firs is generally very poor as this species is highly subject to rot. The ponderosa pine on the other hand is fair to poor since it takes longer to rot, however current stands indicate signs of rotting and blue stain which decreases commercial value.
Due to the lack of roads and steep terrain logging operations would be limited to helicopter logging. Any other method would require road construction, which would increase the damage to soils and watersheds as well as increasing harvest costs. Helicopter logging would also require large landing areas (over 3 acres) as well as roads to provide logging truck access. Helicopter logging costs (2009) range from $800 to over $1000 per thousand board feet. Based on current markets, a timber sale in the area would be unlikely to receive any bids for the following reasons:
• Condition of timber would decrease value
• Long flight distances to adequate landings
• Need to close Hwy 152 while flight operations occurred.
• Lack of mills in general area that would utilize material
• Increased haul costs for low quality timber to mills that could utilize
Background – During the early 2000’s a large area of mixed-conifer was affected by insects, resulting in an estimated 50% tree mortality of mixed-conifer within the South Percha watershed. The area has since gone through the red needle phase, where the standing trees covered in red needles created a very high fire danger, which would promote fire traveling through the crowns. A normal ground fire could have easily spread to the crowns, with a high speed crown fire as the result. The current situation of fine fuels is the needles have dropped to the ground increasing fine fuel loading. This could result in higher rates of spread with a ground fire that could ultimately transition to a green tree crown fire. As time passes the standing dead trees will fall and increase fuel loads in turn increasing fire intensity, residual time and threat to soil conditions. This area is still susceptible to resource damage from high intensity/ high severity fire and will continue in that manner until some type of fuel reduction is accomplished.
Prescribed Fire – Changes in current National Forest policy on prescribed fire and fire management will be required, prior to implementing prescribed fire in the South and Middle Percha and Gallinas watersheds. This policy change is under consideration at the national level and may soon be implemented. The policy change would allow igniting fire in a given location and managing them to reduce fuel loading.
Drawbacks to efficient and effective prescribed fire are as follows:
1. Fire fighter and public safety
2. Boundary locations for holding
3. Potential for not meeting objectives
4. Inability to predict wind speeds and direction
5. Difficulty in acquiring aerial and ground resources
6. Lack of natural and man-made barriers would prevent implementation of burning small areas within the total area
7. Time frame to complete NEPA for implementation
8. Unable to burn during “historic” burning periods
9. Social and economic concerns.
Benefits to using prescribed fire
1. Ability to chose prescription window
2. Ability to choose ignition location/ pattern
3. Benefit to resources in long term.
Managed Fire (Wild land Fire Use)
One of the best tools the Forest Service has is managed fire to reduce fuel loading and minimize the effects of large landscape scale fires. Managed fire is a relatively new tool for the Forest Service. It was previously referred to as Fire Use fires which are naturally occurring fires managed for resource benefits.
Managed fire in the South and Middle Percha and Gallinas watersheds is only feasible under strict fuels and weather parameters.
Drawbacks to efficient and effective Managed Fire use are as follows:
1. Firefighter and public safety
2. Inability to acquire critical resources at critical times (i.e. Fire Season)
3. Small windows of opportunity for implementation
4. Difficulty meeting resource objectives
5. Time frame of getting an ignition in a location to enable fire use
6. Social and economic concerns
Benefits to using Managed Fire
1. Ability to manage over long period of time
2. Typically fires will burn during “historic” fire periods
3. Economic and Social benefits through increased wildlife forage, range forage and hydrologic improvement
Wildlife species evolved with fire on the landscape and although there is some loss of less mobile species, re-colonization occurs quickly. Species associated with the denser stands have already been displaced in the beetle -kill areas and will not return until those conditions return. Low intensity fires tend to benefit wildlife species in general while moderate to high intensity fires can result in longer time periods for re-colonization. Generally speaking fire improves habitat for many species of wildlife. Some species will benefit, some will not.
Scenic Vista/ Recreation Effects
Low intensity fires would have little to no impact on the scenic vistas and recreational opportunities. Moderate to High intensity fires would likely have a negative short term effect. However, if the aspen and big-toothed maples were stimulated by the fire, scenic and recreation opportunities would very likely increase in the near future (5-10 years) and persist for the foreseeable future.
Range Resource Effects
The effects of any fire on the range resource would likely be negative in the short term. However, available forage and water would increase after fire for the next 5-10 years
Possible Effects on Affected Communities
Although the actual period a fire burned would no doubt affect the communities with smoke and ash and general anxiety. These concerns would be relatively short lived and a manageable. However, the flooding concern would not be so temporal or as easily managed.
A worst case scenario would be a large wild fire in late May or June, followed by heavier than normal monsoon rains, or a late season hurricane event before vegetation was able to re-establish within the burn area.
If a moderate to large scale fire occurs in the Emory Pass / Sawyer Peak Area, the Forest Service will work with State and Counties officials to ensure that storm drainages are cleaned, flood warning signs posted, and establish an early warning system through the placement of a Remote Automated Weather Station (RAWS). The Forest Service will work with the County, State and private landowners to install a temporary gauging system upstream of Hillsboro on Percha creek (at its confluence with Middle Percha Creek) to provide residents with as much notice as possible to evacuate. The most critical period would be during the summer monsoons immediately after the fire.
The burned area will be evaluated for treatment with aerial hydro-mulching with seed, ground based hydro-mulching with seed, aerial seeding, mechanical scarification, seed, heritage site protection, noxious weeds treatments, road and trail rehabilitation, maintenance and temporary closures.
The Forest Service will also work with the New Mexico Environmental Department to develop mitigation strategies if wells are compromised due to flooding.
The purpose of this assessment is not to incite worry and paranoia among the residents of Kingston, Hillsboro and the lower Mimbres River Valley. However, we strongly believe in making people aware of the risk and possible outcomes of a wildfire in this area, so we can all be better prepared. A review of possible treatments indicates the following;
1) Logging of the dead trees is not economically feasible.
2) Prescribed fire use is very limited due to a lack of natural or manmade barriers.
3) Wildland fire use is possible but opportunities are limited.
Next steps are to begin working with the communities, Emergency Services, Local Sheriff Departments, Flood Directors and others to develop the appropriate safety measures and contingency plans in advance of a flood situation.
Meanwhile the Gila National Forest will remain diligent in our search for opportunities to mitigate and manage the risk for the good of all involved.