TECHNICAL SPECIALIST REPORT-BAER
Resource: Botany Fire Name: Blue Cut Month/Year: August 2016 Author: Emma Williams, Jordan Zylstra Authors Duty Station: Arapaho-Roosevelt NFs and Pawnee National Grassland, San Bernardino National Forest
I. Resource Condition Assessment
A. Resource Setting The Blue Cut Fire began on Tuesday, August 16th, 2016 in Cajon Pass along Old Cajon Blvd., and burned a total of 36,240 acres of San Bernardino NF. The major plant communities affected by the fire include chamise chaparral, mixed chaparral, big cone douglas fir forest, singleleaf pinyon woodland, Joshua tree woodland, canyon live oak woodland, desert transition scrub oak, alluvial scrub, and cottonwood/willow/sycamore riparian scrub.
Chamise and mixed chaparral are the dominant vegetation communities below 6,500ft in the burn. Chamise chaparral occurs on south and west facing slopes and mixed chaparral predominately occupies northern slopes, drainages, and all slopes at elevations over 3,000 feet within the burn area. These vegetation types are dominated by chamise (Adenostoma fasciculatum), bigberry manzanita (Arctostaphylos glauca), hoaryleaf ceanothus (Ceanothus crassifolius), birchleaf mountain-mahogany (Cercocarpus betuloides), scrub oak (Quercus berberidifolia), California buckwheat (Eriogonum fasiculatum), chaparral yucca (Hesperoyucca whipplei), hairyleaf yerba santa (Eriodictyon crassifolius), and sugar bush (Rhus ovata). Most of the chaparral vegetation burned at a moderate intensity. These plants have evolved with fire and will rapidly regenerate in the burn by sprouting and/or seeding. Fire usually kills any seed on the ground surface, however, buried seed remains insulated from extreme temperatures. Some species, especially those of ceanothus, manzanita, and fire-following herbs, are obligate seeders after fire. Chaparral vegetation recovery will be lower in areas previously disturbed by fuelbreaks and some dozerlines constructed during the 2009 Sheep Fire, 2003 Lytle Fire, and 2002 Blue Cut and Louisiana fires. These fuelbreaks and dozerlines were already in the process of type converting from chaparral vegetation to non-native annual grasslands. Repeated ground disturbance will allow for a further increase in non-native plant dominance in the fuelbreaks. Furthermore, the burn has opened up the chaparral canopy, creating opportunities for weed seed in soil adjacent to fuelbreaks to germinate and outcompete native vegetation, thereby allowing for the continued spread of type converting non-native annuals.
Stands of big-cone Douglas fir (Pseudotsuga menziesii) occur on north facing slopes and drainages along Lytle Creek Ridge Road and the north facing ridgeline running west of Circle Mountain above 4,500 feet. In 2009, the Sheep fire burned the stands on the south facing slopes of Gobbler’s Knob along 3N35. The Blue Cut fire mostly burned around and underneath these stands at a moderate intensity, resulting in observed big cone Douglas fir mortality. Big-cone Douglas firs will sprout after fire; however, the condition of saplings and small burned trees is unclear, and re-sprout depends on burn severity. Given that the affected stands experienced low to moderate burn intensity, higher mortality is expected in trees that were affected by bark beetle and drought before the fire. With the persistence of drought, potential for type conversion to mixed chaparral exists in high intensity burn areas. Mature stands that experienced lower burn intensity will sprout post-fire.
Jeffrey pine forest occurs in a few stands in the higher elevations of Circle Mountain, east of Wrightwood, and burned at low to moderate severity. Jeffrey pine is considered highly fire resistant due to its thick bark, self-pruning branches, and high moisture content needles. Jeffrey pine historically has had short fire intervals of between 9 and 24 years, with these generally being low intensity understory burns. However, fire suppression activities in recent years may lead to an increased understory fuel load and bring higher intensity fires over longer intervals. Portions of the Jeffrey pine stands appear to have most recently burned in 1928, 1940, and 1960.
Singleleaf pinyon pine occurs in the northwest corner of the fire, east of Wrightwood and south of SR-2, generally in the vicinity of Circle Mountain (Photo). Singleleaf pinyon pine is very susceptible to intense fire due to its thin bark and lack of self-pruning. Research has shown that single leaf pinyon can survive a small amount of crown torch, but suffers 100 percent fatality after two-thirds crown scorch. Over half of the pinyon pine communities burned in moderate to high soil burn severity. Historical fire data shows that much of the pinyon community in the fire last burned in 1960, with a smaller portion burning in 1928. The intensities of these fires aren’t known. Singleleaf pinyon is very slow growing, requiring 35 years to produce reproductive cones, and 75-100 years to produce full seed crops. Before the introduction of non-native annual grasses which carry a ground fire between trees, fires would have occurred over a longer interval. Shortened fire intervals may lead to type conversion from pinyon forest to chaparral.
Joshua tree woodland is located in the northern sections of the burn along SR-138 and along SR-2 near Wrightwood. The fire burned at low to moderate severity in these areas (Photo). Joshua trees may sprout from the root crown, rhizomes, or branches following fire. Resprouting may be more frequent in populations above 4000 feet elevation. Fire return intervals in desert ecosystems are generally in the range of 35 to 100 years. Fires in Joshua tree woodland were historically rare, only increasing more recently with the introduction of non-native grasses which alter the fuel structure of the ecosystem. According to historical fire data, the majority of Joshua tree stands in the fire have burned within the last 100 years, including large stands east of SR-138 in the 1999 Turtle Fire.
Canyon live oak woodland mostly occurs throughout the north-facing canyons in the north western section of the burn area. Along Upper Lytle Creek Ridge it contributes to big-cone Douglas fir-canyon live oak forest within a matrix of chaparral. In the Horse Canyon and Circle Mountain it co-occurs with singleaf pinyon and Fremont’s flannel bush. These areas burns at a moderate to high severity and oaks will re-sprout from the root crown and bole after fire. Open patches close to the road may be vulnerable to non-native plant invasions and type conversion. The canyon oak community types within the Blue Cut burn area established under a 30-125 year fire return interval. The majority of stands burned in 1960 or in the 2009 Sheep Fire. Stands that burned in the Sheep fire are at risk of type conversion to chaparral or non-native annual grasslands.
Riversidean alluvial fan scrub occurs within the major drainages of the fire: in Lone Pine Canyon, near Lytle Creek, and in Cajon Wash, and generally burned at low to moderate severity. Alluvial fan scrub occurs in and around flood channels and can experience infrequent but severe flood events. Plants found in this community include scalebroom, yerba santa, California buckwheat, as well as low density cover of many other sagebrush and chaparral species. This is also the habitat for the Federally-listed slenderhorn spineflower, which can grow on stable benches above and adjacent to the stream channel. Although these habitats experienced low to moderate fire severity it is possible but unlikely that the response of the large watershed area upstream could alter habitat condition through debris flows or erosion of benches from flooding.. Cottonwood/Sycamore riparian woodlands and willow scrub occur mostly along Cajon Wash on the southeastern edge of the fire, but also in scattered drainages throughout the burn. Cottonwood, sycamore, and coast live oak generally occur in the larger drainages, with willow scrub and baccharis found more scattered throughout the intermittent drainages. The riparian vegetation generally burned at low to moderate severity, but there were some areas of high severity in Cajon Wash. Much of Cajon Wash last burned in the 2002 Louisiana fire, with large sections of the wash also burning in 1964 and 1928. Riparian areas that burned in low intensity will readily resprout, but high severity areas may be vulnerable to non-native grass and forb invasion as well as vegetation type conversion.
Invasive weed species: Giant reed (Arundo donax), wild oaks (Avena spp), cheat grass (Bromus tectorum), rip gut brome (Bromus diandrus), bull thistle (Cirsium vulgare), Uruguayan pampas grass (Cortaderia selloana), sweet fennel (Foeniculum vulgare), shortpod mustard (Hirschfeldia incana), broadleaved pepperweed (Lepidium latifolium), tree tobacco (Nicotiana glauca), Russian thistle (Salsola tragus), tumble mustard (Sisymbrium altissimum), Spanish broom (Spartium junceum), Smilo grass (Stipa miliacea) and saltcedar (Tamarix ramosissima) are known to occur within the burn area.
Habitat disturbance by non-native plants, increased fire frequencies, and fire suppression activities that affect post-fire native succession may influence vegetation-type conversion and lead altered fire regimes. Type-converted areas likely experienced multiple fire events and short fire return intervals during a season. Close to 57% of the Blue Cut Fire was burned within the last 30 years. Some of these areas, especially dozerlines and roads, are disturbed and type-converted due to previous fires and suppression activities.
Table 1. Fire History and Area in Blue Cut Burn Area. Also, see Figure 1.
Fire Name Fire Year Years Since Fire Acres Percent Cover Stockton 1991 20-30 18 0.05% Crowder 1995 20-30 1252 3.46% Elliot 1999 10-20 944 2.60% Turtle 1999 10-20 2133 5.89% Blue Cut (2002) 2002 10-20 3198 8.82% Louisiana 2002 10-20 5192 14.33% Grandprix 2003 10-20 53 0.15% Runway 2004 10-20 1079 2.98% Sheep 2009 0-10 5635 15.55% Hill 2011 0-10 769 2.12% North 2015 0-10 219 0.61% Blue Cut (2016) 2016 0 36240 100.00%
Figure 1. Fire History within Blue Cut fire perimeter. Areas that have experienced previous fires within the burn perimeter are more likely to be type converted. Areas highlighted with cross hatching may already be converted or are highly likely to be type converted since these places have experienced multiple fires within the last 30 years.
B. Findings of on-the ground survey
Values at risk: During fire suppression activities, 5 drop points and 31.5 miles of dozer/hand line were constructed on Forest Service lands. The fire also impacted 29 miles of trails and 77 miles of roads. These may all serve as weed dispersal corridors. Dispersal of weeds from fire equipment movement poses a significant risk to native plant post-fire regeneration. Even though a weed washing station was brought in, seed could have been transported into the burn on suppression vehicles and equipment that arrived on the fire before the washing station was established. This increases the possibility of suppression equipment acting as weed vectors. Roadsides, dozerlines and handlines will be most impacted by this threat.
Rare Species: The potential values at risk for rare plants inside the burn area are the stability and viability of sensitive plant populations and persistence of the endangered Dodecahema leptocerus. The Forest Service Sensitive plants have suitable habitat within the Blue Cut Fire area (see Table 2).
There is a documented occurrence of endangered plant Dodecahema leptocerus immediately downstream of the burn area in Cajon Wash. Current presence is confirmed with annual monitoring by the Forest Service in recent years.
Table 2. Forest Service Sensitive Plants and watch list species in the Blue Cut Fire Area Scientific Name Common Name Location within Fire Area Habitat Astragalus lentiginosus San Antonio milkvetch Lone Pine Canyon, and suitable habitat var. antonius vicinity of Wrightwood Calochortus Plummer’s mariposa Scattered throughout the suitable habitat plummerae lily southern half of the fire Castilleja plagiotoma Mojave indian Scattered throughout the suitable habitat paintbrush northern half of the fire Chorizanthe xanti var. White-bracted Lytle Creek, Lone Pine suitable habitat leucotheca spineflower Canyon, Cajon Boulevard Dodecahema leptoceras Slenderhorn Cajon wash, 0.25 miles suitable habitat spineflower outside of burn perimeter. No known occurrences in burn Eriogonum umbellatum Alpine sulphur- Cajon wash, and upper Lytle suitable habitat var. minus flowered buckwheat Creek Ridge Galium angustifolium San Antonio Canyon Vicinity of Lone Pine Canyon suitable habitat ssp. gabrielense bedstraw and Swarthout Canyon road Helianthus nuttallii ssp. Los Angeles sunflower Species is presumed extinct. suitable habitat parishii Historical records in Lone Pine Canyon Juglans californica Southern California Vicinity of Cajon Boulevard suitable habitat walnut and Swarthout Canyon road Lilium ocellatum ssp. Ocellated Humboldt Unnamed canyon draining suitable habitat humboldtii lily into Lone Pine Canyon Muhlenbergia California Muhly Cajon wash, south of Cosy suitable habitat californica Dell Opuntia basilaris ssp. Shortjoint beavertail Scattered throughout northern suitable habitat brachyclada half of the fire Schoenus nigricans Black bog-rush Swarthout Canyon road, Lytle suitable habitat Creek, Lone Pine canyon Symphyotrichum San Bernardino aster Lone Pine Canyon nonspecific suitable habitat defoliatum location Syntrichopappus Lemmon’s Scattered throughout Cajon suitable habitat lemmonii syntrichopappus Canyon, and vicinity of Interstate 15
Condition of values at risk:
The condition of the Dodecahema leptocerus occurrence on the benches in Cajon Wash is compromised due to competitive pressure from non-native annual grasses (Photo 1). Although this species occurrences is outside of the burn area, it is possible but unlikely that the response of the large watershed area upstream could alter habitat condition through debris flows or erosion of benches from flooding.
The condition of sensitive plant species in the burn area is not well known; though there is suitable habitat for the sensitive species listed (Table 2), little data is provided on existing populations within the burn area. In general, threatened and sensitive plant species will persist given the following fire events are within the species’ historical fire regime. However, altered fire patterns may impact and cause decline in species that are not adapted to frequent fire.
Weed Species: Many areas in the burn area are dense with annual grasses and non-native annuals (see Noxious Weed Detection Survey Plan). For example, wild oats, ripgut brome, red brome, cheatgrass, tocalote, Russian thistle, and shortpod mustard were scattered throughout the fire area, with the highest concentrations occurring along roads. Many of the individuals were burned, however significant patches of infestations persisted and many of the seeds in the soil bank probably survived due to their high heat tolerance and low/moderate burn intensity. There is a high likelihood that these infestations could greatly hinder the regeneration of native vegetation, especially in the early seral stages, through increased fire intervals and competition for nutrients.
II. Emergency Determination The unknowing introduction and dispersal of invasive weeds into areas disturbed by fire suppression and rehabilitation has the potential to establish persistent weed populations. In addition, it is highly likely that existent weed infestations will increase in the burn area, due to their accelerated growth and reproduction and a release from competition with natives. These weed populations could affect the structure and habitat function of native plant communities within the burn area. It is expected that most native vegetation would recover if weed invasions are minimized. The high potential for the Blue Cut Fire to increase the dominance of several invasive plant species on the Forest, especially in desert transition scrub oak, constitutes an emergency.
III. Treatments to Mitigate the Botanical Emergency A. Treatment Type: 1. Weed detection surveys 2. Weed infestation treatment 3. Treatment effectiveness monitoring
B. Treatment Objective: 1. Accelerated vegetation re-growth/restoration 2. Decreased disturbance and weed establishment/dispersal 3. Early detection of weed invasions and consequent manageable eradication
C. Treatment Description: 1. Conduct weed detection surveys (described in the weed detection survey report)
IV. Discussion/Summary/Recommendations I recommend weed detection surveys for at least one year post fire, as there is a high potential for weed invasions (see Noxious Weed Detection Survey and Rapid Response Plan). Any new or expanding invasive species will be removed.
Caption: Caption: Slenderhorn spineflower habitat, at Cajon Burned singleleaf pinyon woodland, on 3N35 Wash, immediately southeast of fire perimeter east of Circle Mountain
Caption: Caption: Joshua tree woodland along 3N35 west of HWY-138.
Blue Cut Fire Engineering BAER Report
Resource Specialty: Engineering- Transportation and Dams Fire Name: Blue Cut, San Bernardino NF Month and Year: August, 2016 Author(s) Name and Home unit Name: Joshua Direen, PE, San Bernardino NF Damon Romero, PE, San Bernardino NF
I. Potential Values at Risk (identified prior to the on-the-ground survey)
A. Critical Values: (1) Property: National Forest System Roads (NFSR) within and adjacent to burned area, (2) National Forest Dams, (3) Cooperator roads on NF lands, (4) State highways and roads, (5) Human Life and Safety, (6) Natural Resources-Water Quality
B. Resource Condition Assessment
a) Resource Setting
The Nation Forest transportation system consists of approximately 77 miles of National Forest System Roads (NFSR) within the fire perimeter. Of the 77 miles of NFSR within the fire perimeter, approximately 41 miles are suitable for passenger cars (maintenance levels 3-5) and 36 miles are suitable for high- clearance vehicles and/or are administrative use only (maintenance level 2). Main highways within the burned area include State highway 15 and 138 and include approximately 24 miles within the burned area. Main county roads in and near the burned area include: Lytle Creek Road, Swarthout Canyon Road, Cajon Blvd. (old Route 66), Keenbrook Road, and Lone Pine Canyon Road. Approximately 120 miles of County and local roads exist within the burned area.
Four railroad lines exist within the burned area and are operated by BNSF and Union Pacific (UP). The existing railroad alignments pass through moderate to high burn severity and consist of one single line (Union Pacific) on the westerly side and three tracks on the easterly side. Original construction of the railroads date back to the 1880’s.
Other infrastructure surveyed in this report includes the Keenbrook Dam and Sheep Canyon Dam. The Keenbrook dam was believed to have been installed in the late 1930’s or 1940’s as a flood control structure. The Sheep Canyon Dam was installed in the 1940’s as a flood control structure. Both dams are on the Forest dam inventory.
b) Findings of the On-The-Ground Survey
The field survey was conducted over the course of 4 days from August 25- Augusts 28, 2015. State, County, National Forest System, local, and cooperator roads were assessed in order to determine the probability and magnitude of road damage or loss as a result of the changed watershed condition. Public safety on roads in the burned area is also an equally important consideration. Non-NFS
Blue Cut Fire Engineering Roads Report – Page 1 roads were surveyed since their failure can have negative impacts on water quality and other infrastructure if they were to fail.
Many NFS roads suitable for passenger cars and high-clearance exist within and adjacent to the burn area. Refer to Appendix 1 for a list of NFS roads. Many cooperator roads are NFS roads open to the public and maintenance is either shared or accomplished by the individual cooperators. Many cooperator roads and spur roads are not on the NF road system and most still require formal cooperative road maintenance agreements. It is highly recommended that cooperators are engaged to ensure their roads are adequately storm-proofed prior to the rainy season. Appendix 2a through 2c shows the list of NFS roads not proposed for treatments, NFS roads proposed for treatments, and recommended treatments for roads primarily maintained by Forest Service cooperators.
The road infrastructure within the burned area is at increased risk of damage and failure due to:
1. Additional erosion damage as a result of increased storm water runoff velocity and volume on and across the roads. 2. Potential degradation of road surfaces resulting from fire suppression activities if not properly rehabilitated during suppression rehab.
Other cooperator spur roads exist within the burned area, which are used to access critical infrastructure in the area. Not all cooperator roads were surveyed, however coordination of road storm-proofing is needed due to the potential impacts these roads can have on water quality and surrounding infrastructure if they suddenly fail during a storm event.
Keenbrook Dam is located just up channel from the Union Pacific and BNSF rail lines. The Forest is unable to confirm the original construction date, however it is believed the dam was constructed for flood control purposes after the 1938 floods. The forest does not have records of the dam being maintained or cleaned in its history and the basin is completely full of sediment with no storage capacity. The existing concrete spillway has some scour at the outlet that could be exacerbated by the increased runoff. An existing side channel is directing flow toward the southern embankment section of the dam with a mostly moderate to severely burned tributary drainage. Large trees are located just upstream of the spillway and could contribute to woody debris in the channel. The culvert below the UP rail line is large (10 feet in diameter) and capable of passing large storm events and debris, however there are some issues with embankment erosion above the culvert and the current headwall is inadequate.
The Sheep Canyon Dam is located in Sheep Canyon above Applewhite road. The original timber spillway burned in 2009 during the Sheep Fire and was repaired and armored in 2010-11. The dam basin was cleared at that time to increase storage capacity. Many of the slopes in Sheep Canyon had a moderate burn severity, although most of the slopes did not burn as hot since the vegetation was previously burned in the Sheep Fire. The channel upstream of the dam is gradual and has a long runoff length. c) Consequences of the Fire on Values at Risk
Blue Cut Fire Engineering Roads Report – Page 2
The potential consequences of the burned area on infrastructure are: 1. Potential damage and localized failures to road surfaces, road fill slopes, road drainage structures, dam embankment and spillway, rail embankments, rail tracks, and rail drainage structures. 2. Potential secondary impacts to adjacent watersheds and other infrastructure as a result of infrastructure damage and/or failure. 3. Reduced public safety due to increased hazards resulting from destabilized rock slopes, falling trees, potential debris flows and flooding, and damage to traffic safety structures.
II. Risk Assessment
A. Summary
Risk ratings were determined using the BAER Risk assessment matrix in Forest Service Manual 2520. Risk ratings are based on the probability of damage or loss of a critical value at risk and the magnitude of consequences if the value is damaged or a complete loss. Forest Service Roads, cooperator roads, dams, and railroads are considered critical property values on National Forest land. Other critical values taken into consideration with roads and infrastructure include protection of human life and safety and protection of water and other natural resources. An emergency determination was made for critical values with a high to very high risk rating of failure or damage. Treatments are proposed to mitigate the level of risk to a more acceptable level for values with an emergency determination.
B. Emergency Determination
Imminent hazards to the roads system within the burned area and within NF lands. These hazards vary from minor sloughing and culvert blockage to partial or total loss of road template. A risk assessment was conducted on the potentially affected roads. The tables below shows the Forest Service roads and cooperator roads determined to be an emergency and have a high or very high risk of failure:
Table 1: Risk Assessment of NFS roads
Road Assessment Risk
Level 3 (passenger car) road. Public and LADWP 2N53 Very High transmission tower access road (shared use)
3N06 Level 4 (passenger car) road. High
Level 2 access road, OHV route. West section low 3N24 burn intensity and located on ridge. East section low High to moderate burn severity.
Blue Cut Fire Engineering Roads Report – Page 3 Level 2 (High Clearance) road. Located in moderate 3N29 Very High to high burn severity. Level 3 road open to public. Shared use with SCE. 3N31 Ridge road with some moderate to high burn intensity High above road. 3N31Y Level 3 access road. Located on ridge. Low to moderate burn severity. High
Level 2 road. Moderate to high burn severity. Steep 3N33 Very High and erodible slopes.
Level 3 road open to the public. LADWP transmission 3N49 High tower access road.
Table 2: Risk Assessment of Cooperator Maintained Roads
Road Assessment Risk Level 2 (High Clearance) road open to public. 2N52 Very High LADWP transmission tower access road.
Private Road and SCE transmission tower access 2N61 Low road. Gated.
Level 2 admin. road. Gated. SCE transmission 2N87 Intermediate tower access road
Level 3 road open to public. Road parallels train 2N89 Very High track. Union Pacific railroad access road. Level 3 road open to the public. LADWP 3N49 High transmission tower access road. Level 2 and 3 road. LADWP transmission tower 3N55 High access road. Swarthout S.B. County road located in and adjacent to High Cyn. Road burned area drainages.
Lone Pine S.B. County road located in and adjacent to High Cyn. Road burned area drainages.
Lytle Creek S.B County road located adjacent to burned area High Road drainages Interstate 15 Caltrans interstate freeway Intermediate Highway 138 Caltrans State highway Intermediate SCE access Located off of primary routes to tower pads High spur roads LADWP access spur Located off of primary routes to tower pads High roads So Cal Gas Access roads to high pressure gas line High access roads infrastructure.
Blue Cut Fire Engineering Roads Report – Page 4
Additional information on the high/very high risk roads is listed in appendix 2b and 2c. Other roads in the fire area not listed in the above table are shown in Appendix 2 and were determined to be a low to intermediate risk. Prescription of treatments is not proposed for values at risk with a low to intermediate risk and the roads do not pose an imminent threat or emergency.
Imminent hazards to the Keenbrook Dam and infrastructure downstream exist and constitute an emergency. Potential consequences to the infrastructure due to the burned area include increased sedimentation and debris in existing drainages and potential for partial or total loss/failure of the dam and downstream railroad infrastructure. Because of the likely probability and potential for major magnitude of consequences of damage or loss, it was determined the Keenbrook Dam has a “Very High” risk rating. Treatments are proposed for Keenbrook Dam to mitigate the level of risk to a more acceptable level.
The Sheep Canyon Dam was determined to have an intermediate risk of damage or loss. The probability of damage or loss is possible and the magnitude of consequences would be moderate if the dam failed. Because recent storm- proofing of the spillway and cleanout of the basin was performed, no treatments are proposed. Post-storm inspections should be performed while performing road inspections to ensure
C. Treatments to Mitigate the Emergency
Roads
Road drainage features are at risk from adjacent burned watersheds. Increased runoff and sediment from the burned areas can negatively affect the road prism, damaging the road, eroding land downslope of the road and routing flow and sediment directly to stream channels. Road failure can also contribute to failure of infrastructure downstream. Culverts associated with these roads are at risk of plugging from debris carried down channels from burned watersheds. Some culverts are undersized for the expected increases in peak flows and are at risk of failure from overtopping. Culvert failures may increase the magnitude of flood, sediment and erosion hazards of downstream infrastructure and private lands and increase scouring of stream channels on NFS lands.
a) Treatment Types: Proposed road treatments include: drainage structure cleaning, additional drainage structure overside drains, culvert repairs and removal, culvert inlet modifications, public safety warning and road closure signs, road closure gates, rolling dips, and riprap armoring of slopes and drains. A summary of treatments for each road are noted in Appendix 2a and 2b - Evaluation and Assessment.
b) Treatment Objectives: The primary objectives of the road treatments are to:
1. Protect and stabilize the transportation system roads at risk of damage as a result of increased sedimentation and erosion from the fire. 2. Increased protection of water quality by reducing risk of road damage and failure.
Blue Cut Fire Engineering Roads Report – Page 5 3. Mitigate public safety hazards associated with hazard trees, flooding, rock fall, and debris flows along NFS roads. c) Treatment Descriptions: Descriptions for proposed road treatments for each road are located in Appendix 6. d) Treatment Costs: Proposed road treatment costs were estimated for each road and are shown in Appendix 3. e) Probability of Completing Treatment Prior to First Damaging Storm Event
All High/Very High Risk Roads: 80% f) Probability of Treatment Success
Risk Level Year 1 Year 2 Year 3
High/Very High Risk 85% 80% 70% Roads
Dams:
The Keenbrook Dam is at high risk of damage or failure from the above watershed, which was almost entirely moderate to high burn severity. Dam failure poses a very high risk to the downstream railroad infrastructure failure. Specific treatment measures have been identified that will help reduce the risk of damage to the dam and other infrastructure below the dam. a) Treatment Types: Proposed dam treatments include: removal of upchannel loose woody debris and earthwork movement to redirect side and main channel away from the dam earthen embankment. b) Treatment Objectives: The proposed treatment objectives are: to protect and stabilize the dam infrastructure and to reduce the risk of failure, reduce risk to railroad infrastructure below the dam, and increased protection of water and other natural resources. c) Treatment Description: The proposed treatments are:
1. Earthwork reshaping and relocating with a mechanized dozer. Move material deposited from south side channel next to dam and direct channel away dam rembankment. Reshape the main channel to direct toward the center of the dam reservoir. Move some material out of the channel located directly above spillway. Estimated dozer time is two working days. 2. Removal of loose woody debris upstream to reduce plugging to culvert downstream of dam spillway. Estimated two days with a small hand crew of 5 people.
Cooperator Roads:
Blue Cut Fire Engineering Roads Report – Page 6
Many cooperator roads are at a high to very high risk of damage or failure as a result of the burned watershed condition. Initial coordination has taken place with Southern California Edison (SCE), Los Angeles Dept. of Water and Power (LADWP), and Union Pacific. Recommended treatment descriptions are located in appendix 2c. Continued coordination will be needed to help facilitate review of treatments on NF lands and to ensure treatments are implemented in a timely manner prior to the rainy season. The treatment cost for coordination and Forest Service staff time has been incorporated in the interagency coordination section of the main BAER report. Initial coordination has also taken place with Caltrans and San Bernardino County Public Works to discuss potential impacts and treatments to the public roads they manage.
III. Discussion/Summary/Recommendations.
The majority of National Forest roads are built with native materials, ranging from bedrock to decomposed granite (DG) and alluvial deposits. The NF roads within the burned area are primarily native surface, with a few roads having asphalt surfacing. Native surface roads are at an increased susceptibility to erosion from the burned watershed condition as a result of the fire. Additionally, lack of routine maintenance on many of the roads is a serious concern and has resulted in significant surface and template degradation in many locations. Forest Service dams are also rarely cleaned out or maintained, thus offering far less protection than when they were initially installed.
Although BAER road treatments are not intended to correct past maintenance deficiencies, the drastically changed conditions resulting from wildfire impose urgency for correction on high and very high risk roads. The proposed road and dam treatments are necessary to protect and stabilize National Forest infrastructure against increased erosion and sedimentation from post-fire storm water runoff. Additionally, several road treatments are intended to mitigate potential public safety hazards from potential debris flows within and adjacent to National Forest system roads. Road Treatment recommendations and associated cost estimates are noted in the Appendices.
Coordination with cooperators with infrastructure in and near the burned area is critical to increase awareness of the potential impacts post-fire storm effects can have to their infrastructure. Lack of maintenance of drainage structures was a common theme on all cooperator, state, and local roads in and near the burned area. Cleaning and storm- proofing of existing drainage structures prior to the rainy season is recommended for all National Forest, cooperator, state, and local roads and other infrastructure in and near the burned area. Additionally, it is recommended entities review and update their storm inspection and response plans for maintaining infrastructure in and near the burned area.
IV. References
A. FSM 2500, Chapter 2520 – Watershed Protection and Management, 2523 – Emergency Stabilization-Burned Area Emergency Response B. Standard Specifications for the Construction of Roads and Bridges on Federal Highway Projects, FP-03 C. FSM 7700 – Travel Management, Chapter 7730-Road Operation and Maintenance D. Appendices
Blue Cut Fire Engineering Roads Report – Page 7
Blue Cut Fire Engineering Roads Report – Page 8
Blue Cut Fire Heritage BAER Report
Resource Specialty: Heritage Fire Name: Blue Cut Month and Year: August 2016 Author(s) Name and Home Unit Name: Jay Marshall, San Bernardino National Forest Dorit Buckley, El Dorado National Forest
I. Potential Values at Risk (identified prior to the on-the-ground survey) A. Critical Values Heritage values at risk include prehistoric and historic archaeological sites and ethnographic locations. Many of these values are fragile and their loss is considered irreversible. Examples of these non-renewable resources include the data potentials contained in archaeological deposits with regard to prehistoric populations, environments, and climates as well as historic land use associated with the history of the San Bernardino area. In addition, the local Native American communities are strongly connected to their ancestral lands and cultural heritage located in the vicinity and are vocal in expressing their concerns.
Wildfires have the potential to damage or destroy cultural resources through: (1) direct effects of the fire; (2) ground disturbing suppression or rehabilitation activities; (3) and erosive soil movement caused by subsequent storm precipitation. These impacts may completely destroy prehistoric and historic resources or alter the context of surface and subsurface deposits vital to scientific analysis or interpretation. Wildfires also increase the accessibility and visibility of archaeological site locations making them more susceptible to vandalism, looting and unauthorized recreational activity.
Damage of archaeological materials on National Forest lands is of particular high concern due to OHV activity. Ground visibility and access has been greatly enhanced due to the removal of vegetative groundcover by the fire. Loss or destruction of archaeological materials can be expected as a result of this increased visibility and access.
B. Resource Condition Assessment
(a) Resource Setting Archaic groups (ca. 8,000-1,500 BP) exploited the general area for thousands of years, hunting deer, rabbits, and other fauna, and harvesting yucca, pinyon, and other floral resources. Towards the end of the archaic period, a weapons-system shift from the atlatl to bow and arrow use occurred. Concurrent with the adaptation of the bow and arrow came a host of technological and cultural changes including the manufacture of ceramics, decreased nomadism, regional differentiation, and extensive trade networks.
Appendix E: Survey Team Specialist Report Format – Page 1 The Serrano (Spanish for “mountaineer”) Indians occupied this area of the San Bernardino Mountains at the time of European settlement. According to ethnographic sources the area was likely within the territory of the Amutskajam (Bean et al 1981) or the Amutcakaiem (Stong 1929).
Predicted land use includes seasonal occupation sites, coinciding with hunting, gathering, and food processing activities. Artifacts and features expected as a result of these types of activity include but are not limited to, flaked stone tools and debitage representing tool use, production, or quarry activity, millingstones associated with food processing, cooking features, and midden deposits.
Vestiges of historic period sites include pioneer trails, refuse dumps, mines and quarries, cabin sites, rock walls, and historic roads and railroads. All of these have the potential to be present in the fire area. An archaeological records search was conducted to ascertain the presence of known cultural resources within and adjacent the burn area. Approximately 100 archaeological sites are known to be within the fire perimeter. Selecting cultural resources to assess involved four steps: 1. Select sites that are eligible or potentially eligible for listing on the National Register of Historic Places based on criteria as described in 36 CFR 60.4. 2. Select sites that are inheritably at greater risk of destruction due to the characteristics they possess. 3. Overlay of the known burn intensity, slope, and stream shed information in a GIS with the locations of the various cultural resources. 4. Accessibility of sites.
(b) Findings of the On-The-Ground Survey
Twenty-three sites were identified for on-the-ground assessment based on their location, burn severity, and the possibility of debris flow damage. The remaining sites were not visited due to safety concerns, a lack of potential BAER issues, or the necessity to prioritize a large assessment in a relatively short amount of time.
Eight cultural resources (six prehistoric, two historic) have been identified as at risk from post-fire effects. One historic property, the historic LADWP Boulder transmission (CA-SBR-7694H) line, runs the length of the Cajon Pass and is responsible for transmitting electric power from Hoover dam to Los Angeles. The towers are susceptible to an increase in erosion, debris flows, and flooding due to the effects of the fire.
The remaining seven of these historic properties overlap with a heavily used recreation area (mostly off-highway-vehicle [OHV]) which makes these sites particularly vulnerable to increased disturbance. Given the extent of private land adjacent to and within the fire area, the loss of vegetative barriers due to the fire, and the amount of unauthorized cross country OHV use, the protection of cultural resources from the effects of off route use in this location is a concern. The sites of concern are:
CA-SBR-4411H. The “Mormon Trail”. This portion of the trail was laid out as a summit crossing of Baldy Mesa in 1850. The trail was used by Moron Pioneers to enter the San Bernardino Valley.
Appendix E: Survey Team Specialist Report Format – Page 2
CA-SBR-9954. A seasonal vegetal procurement and processing site that may have been inhabited by relatively large numbers of people at any given time.
CA-SBR-9956. Prehistoric plant processing and lithic testing/reduction activity area.
CA-SBR-9957. This prehistoric site is recorded as containing at least 34 artifacts, including millingstones, handstones, cores and core tools, chopping tools, and lithic flakes of imported and local materials. Ashy midden deposits are also extant
CA-SBR-10077. Prehistoric vegetation processing and lithic testing/ reduction activity. Use wear on the manos indicates that the site was repeatedly occupied and may represent site that was ancillary to a large habitation.
CA-SBR-10076. This is a small prehistoric plant processing site. The extensive use wear on the metate suggests seasonal occupation and may represent a satellite resource procurement and processing site that was ancillary to a large habitation.
CA-SBR-10078. This large site includes an artifact scatter consisting primarily of ground stone and flaked stone artifacts, hammerstones, and debitage. The site contains multiple bifaces, formal milling equipment, numerous expedient cutting implements, and a relatively high incidence of imported lithic materials. This site has been evaluated as eligible of the NRHP.
(c) Consequences of the fire on values at risk
The increase in visibility will likely lead to increased off-trail OHV use. Features and artifacts on the surface can be damaged or destroyed by unauthorized OHV use and can lead to significant damage at many archaeological sites. OHV impacts at sites can also enable looters to access public land that would otherwise be inaccessible. These disturbances, primarily the damage to features and subsurface deposits, can destroy the site’s data potential and integrity which will adversely the site.
Erosion, debris flows, or flooding could damage or destroy some of the historic towers of the LADWP line. In addition to the damage of an historic property, interruption of the line will affect the availability of electricity in Los Angeles.
II. BAER Risk Assessment Refer to: Chapter 2520 - Watershed Protection and Management
Probability Magnitude of Consequences of Damage Major Moderate Minor or Loss RISK Very Likely Very High Very High Low Likely Very High High Low Possible High Intermediate Low
Appendix E: Survey Team Specialist Report Format – Page 3 Unlikely Intermediate Low Very Low
Summary:
The probability of damage or loss to seven of the sites is “likely” due to the potential for increased unauthorized OHV activity through the burn area where vegetative cover once protected the area from OHV access. The magnitude of consequences is considered “moderate” because the potential for increased and continual unauthorized activity in the area of these sites could result in additional user created trails into the site areas, erosion from these trails, damage to features, and displacement of artifacts, and the potential for looting and vandalism. As long as problems are identified and corrected timely, it would not necessarily be irreversible, although it would contribute to long lasting effects to the sites. Therefore, the risk to these sites is considered “high”, especially because of the heavy OHV use in this area.
The possibility of damage to CA-SBR-7694H is “likely” and the magnitude of consequence is “major”. This constitutes a “very high” risk.
C. Emergency Determination –
Treatments are needed for the sites that are vulnerable to increased OHV activity and a separate treatment is required for the property that is vulnerable to the effects of increased erosion and flooding.
D. Treatments to Mitigate the Emergency
(a) Treatment Type The BAER assessment team has proposed an OHV Resource Protection treatment that includes installation of barriers, gates, fencing, and vegetation barriers to try to limit the amount of illegal cross-country vehicle use that is expected due to the lack of vegetation. The OHV Resource Protection treatment will reduce the risk of damage to historic properties from vehicles driving off road. It will also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non-native plants.
Treatment for CA-SBR-7694H is to contact LADWP to evaluate required protection measures.
III. Discussion/Summary/Recommendations
The Blue Cut Fire has increased the accessibility and visibility of archaeological sites making the probability of loss from vandalism/artifact looting and unauthorized recreational activity possible. The magnitude of consequences is moderate. The Blue Cut Fire has put Heritage resources at a high risk of looting and/or unauthorized recreational access. It is recommended that the OHV
Appendix E: Survey Team Specialist Report Format – Page 4 resource protection treatment is applied to protect those at risk historic properties.
Because proposed BAER treatments from the team have not been finalized at the time of this summary, no cultural assessment for Section 106 cultural compliance work was completed during the fieldwork conducted. Any proposed ground disturbing treatments including but not limited to, gates or fencing or other barriers in or near archaeological sites, that the Forest plans to implement will require an archaeologist to review for potential impacts to cultural resources. Although much of the burn area within Forest Service boundaries has been previously surveyed, it is recommended that an archaeologist be present to monitor particular areas of proposed work due to the burn off of vegetative cover potentially exposing additional artifacts and features that were not previously visible.
IV. References
Bean, Lowell J. and Sylvia B Vane, Michael Lerch, and Jackson Young 1981 Native American Place Names in the San Bernardino National Forest, San Bernardino and Riverside Counties, California. Report prepared by Cultural Systems Research, Inc., Menlo Park, California, for the U.S. Forest Service, San Bernardino National Forest, San Bernardino. Strong, William D. 1929 Aboriginal Society in Southern California. University of California Publications in American Archaeology and Ethnology 26(1):1-358).
V. Appendices
Appendix E: Survey Team Specialist Report Format – Page 5 WATERSHED ASSESSMENT
BLUE CUT FIRE SAN BERNARDINO NATIONAL FOREST
September 7, 2016
Emily Fudge, Forest Hydrologist, Cleveland National Forest Becky Biglow, Hydrologist Casey Shannon, Hydrologic Technician, Inyo National Forest
I. RESOURCE CONDITION ASSESSMENT
A. RESOURCE SETTING
The Blue Cut fire burned 36,240 acres, the majority of the fire within the lower and upper Cajon Wash watersheds on the San Bernardino National Forest. The fire burned in surrounding watersheds such as North Fork Lytle Creek along the southern perimeter and Manzanita Creek along the northern perimeter, and burned into the high desert regions to the north. The fire burned between 2,400 feet elevation at Cajon Wash to 6,955 feet elevation on Lytle Creek Ridge in the San Gabriel Mountains. The Cajon Wash and tributaries dominate the watershed setting of the fire, and the San Gabriel Mountain Range to the west have elevations reaching 10,000 feet at the head of North Fork Lytle Creek. The drainage headwaters are steep and confined, flowing into extended and anastomosed low gradient channels and washes (alluvial fans and plains) with wide valleys such as Cajon Canyon, Lone Pine Canyon and Lower Cajon Wash. Lytle Creek and Cajon Wash merge below the mountains and flow into the Santa Ana River near San Bernardino.
Most of the streams have seasonal flow, usually from large storm events or during wet winter rain seasons and typically turn dry during the summer. Cajon Wash and Lytle Creek have sections of perennial stream flow. Primary streams can flow for extended periods during wet winters further down reaches and reach the Santa Ana River to the Pacific Ocean. The northern streams beyond the Cajon watershed flow into the Mojave River system to sinks. Streams can flood during storms and flow at high rates during the winter. In 1938 and 1969 when significant storms occurred, Lytle Creek near the mouth of the canyon had peak flows estimated to be 26,000 and 35,900 cubic feet per second, respectively.
The majority of precipitation in the area occurs from October through April, with the bulk coming from December through March. Summers are warm and occasional summer convective storms, or monsoon storms can produce sudden and heavy rainfall that can cause flooding. Snowfall occurs in elevations above 5,000 feet in winter and high elevation snowpack can develop. Annual precipitation is greatest within the upper Lytle Creek watershed along the south facing front of the San Gabriel range. The upper reaches of the Cajon watershed tend to have lower annual precipitation due to rain shadowing as storms release the bulk of precipitation on the San Gabriel Range before reaching the upper Cajon watershed.
The San Gabriel range rises abruptly from coastal valleys in an east to west orientation, where moisture from Pacific frontal systems is directed from the south to southwest. Storms tend to build along the range causing an orographic lift effect that can lead to significant amounts of precipitation if storm dynamics are in place. Average annual precipitation in Upper Lytle watershed is near 40 inches, 20 inches in the lower Cajon Wash, and 15 inches in the northern area of the fire near Baldy Mesa and Manzanita Creek. Powerful winter storms that tap into deep sub-tropical moisture can create high, intense rainfall rates on mountain slopes and are the storms that can cause significant flooding and debris flows in the major drainages. Although not common, these storms tend to be warmer with high snow levels, and warm heavy rain on existing snowpack can cause even larger floods that have historically caused damage to roads and infrastructure along the major streams and alluvial fans.
1. Beneficial Uses and Water Quality
a) Beneficial Uses of Water – Santa Ana River Water Quality Control Board (SARWQCB), State of California)
Beneficial Uses (BU’s) are the natural and human uses of surface water and are defined in the State of California Water Quality Control Board Basin Plans. These beneficial uses must be maintained.
Two major watersheds within the Blue Cut Fire area fall under the Santa Ana River Water Quality Control Board’s jurisdiction: Lytle Creek and Cajon Canyon Creek. Both streams fall within the same Hydrologic Unit Code (Cajon Canyon Creek – Lytle Creek HUC 1807020300305). Beneficial Uses of water of these streams, classified as inland surface waters within the Santa Ana River watershed, as referenced from the Santa Ana River Water Quality Board Basin Plan (SARWQCB 1995), included on the following tables:
Table 1: Beneficial Uses of Water for Lytle Creek
Beneficial Lytle Creek (HUC 1807020300305) Use Code MUN Municipal and Domestic Supply AGR Agricultural Supply GWR Groundwater Recharge IND Industrial Service Supply PROC Industrial Process Supply REC-1 Water Contact Recreation REC-2 Non-contact Water Recreation COLD Cold Freshwater Habitat WILD Wildlife Habitat RARE Rare, Threatened or Endangered Species POW Hydropower Generation
Table 2: Beneficial Uses of Water for Cajon Canyon Creek
Beneficial Cajon Canyon Creek (HUC 1807020300305) Use Code MUN Municipal and Domestic Supply GWR Groundwater Recharge REC-1 Water Contact Recreation REC-2 Non-contact Water Recreation COLD Cold Freshwater Habitat WILD Wildlife Habitat RARE Rare, Threatened or Endangered Species
b) Threats to Water Quality and Beneficial Uses of Water
Peak flow increases from the fire will also be bulked by ash, debris and other floatable and transportable material within stream channel areas of the fire. Temporary episodes of water quality degradation and fine siltation is likely during the first year after the fire to Cajon Canyon Creek and major tributaries. Less severe and localized water quality impacts to North Fork Lytle Creek below burned tributaries upstream and adjacent to the Lytle Creek residential area and downstream could occur. Beyond the first year, post-fire water quality impacts will be lessened as the burned watersheds recover. Beneficial uses listed above in Tables 1-2 could experience temporary impacts post-fire. B. POST-FIRE SOIL SURVEY RESULTS
The BAER soils scientists field verified the Burn Area Reflectance Classification (BARC) map, which is used to estimate soil burn severity (SBS). Description of methods (both development of the BARC and field verification methods) to determine SBS are described in detail in the Blue Cut Fire Soils Report. Soil burn severity ratings include careful consideration of factors such as, amount and condition of residual ground cover, viability of native seed banks, condition of residual fine roots, degree of fire- induced water-repellency, soil physical factors (texture, structural stability, porosity, restricted drainage), soil chemical factors (oxidation, altered nutrient status), and topography (slope gradient, length, and profile), and the length of time heat from the fire has been in contact with the soil (residence time). Hydrologic function, runoff, and erosion potential are influenced by pre-fire, fire, and post-fire environments. Final ratings for SBS of the Blue Cut Fire are listed in Table 3 (Appendix A, Map 1).
Table 3: Blue Cut BAER Soil Burn Severity (2/Sept/2016)
Soil Burn Severity Acres % Fire Area Unburned/Very Low 6,205 17% Low 12,505 35% Moderate 15,678 43% High 1,852 5% Total: 36,240
II. IDENTIFICATION OF VALUES AT RISK, RISK DETERMINATION, AND TREATMENT RECOMMENDATIONS
A. ON-THE-GROUND FINDINGS
An initial list of potential values at risk was identified by the team early in the assessment process. According to policy direction, such values are determined as critical if they fall within the categories below. Table 4: Taken from FSH BAER Direction HUMAN LIFE AND SAFETY Human life and safety on National Forest System (NFS) lands. PROPERTY Buildings, water systems, utility systems, roads and trails, dams, wells and other significant improvements on NFS lands. NATURAL RESOURCES Water used for municipal, domestic, hydropower, or agricultural supply or waters with special Federal or State designations on NFS lands.
Some of the potential critical values identified included:
• Life and Safety o Forest Service recreation areas, such as campgrounds, picnic areas, and recreation residences at risk from flooding, erosion, sedimentation, debris flow, and rock fall. o Low-water crossings at risk of flooding, sedimentation, erosion, and debris flow. o Private residences off forest at risk from flooding, erosion, sedimentation, debris flows, and rock fall. • Property o Infrastructure, transmission lines, pipelines, road, railroads, highways, special uses on the forest, and dams at risk from flooding, erosion, sedimentation, debris flow, and rock fall. o Private property at risk from flooding, sedimentation, erosion and debris flow, and rock fall. o Forest Service roads, trails, and facilities at risk from flooding, erosion, debris flow, and rock fall. • Natural Resources o Domestic water at risk from ash and sediment. o Water bodies (Lost Lake) at risk from ash and sediment. o Downstream water quality at risk from hazardous material burned in the fire. o T & E species habitat at risk from flooding, sedimentation, erosion, and debris flow.
These values were assessed in the field and through runoff, erosion, and debris flow modelling. Assessment results of on-the-ground findings/observations, modeling results, risk determinations, and recommended treatments are discussed in detail in the following sections and Table 5.
Figure 1. Several Values At Risk were identified in the assessment: private residences, roads, railroads, highways, utility lines, transmission lines, T&E species habitat, etc.
Table 5: Values at Risk: Field Observations, Risk Assessment and Recommended Treatments, Blue Cut Fire
Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Sheep Canyon Property Risk of sedimentation and erosion. Debris Very Likely Minor Low No treatment Debris Basin basin has storage capacity. Outlet has some erosion near spillway. Sheep Canyon Property Risk of flooding and sedimentation. Loss of Likely Major Very High Advise Engineering Staff. Road 2N56 Low access. Crossing is located in a depositional Recommend closure. Water Crossing area. Applewhite Road Property Risk of flooding, debris flow, road damage, Likely Major Very High Advise Engineering Staff of 2N55 at Sheep diversion potential. Culvert drains main stem findings. Upgrade culvert Canyon Culvert and additional hillslope/swale drainages capacity and storm patrol. diverted by road ditches. Sediment charged Temporary road closure. swales with material that could be mobilized. Lytle Creek Life and Risk of flooding and undercutting. Building on Possible Moderate Intermediate No treatment Senior Safety, high terrace out of hazard from flooding. Community Property Located on opposite side of creek (cut bank Center bend) from burned slope. Lytle Creek Property Risk of road and property damage due to Likely Major Very High Consult with SB County Public Road/Sheep flooding, plugging and diversion potential. Works. Canyon Culvert Drains to Applewhite Picnic area. Concrete Close lower portion of tunnel has potential to plug, may be undersized Applewhite Picnic Area. for modeled flows and additional post-fire sediment estimates. If tunnel plugs, water and sediment could either flow into the Applewhite Picnic area (lower half) or down Lytle Creek road for some distance. (See modeled pour point.) Forest Service Life and Risk of flooding, debris flow, rock fall, and Likely Major Very High Close campground. Applewhite Safety, sedimentation. Poses a safety threat to visitors. Campground Property Site is located at the base of a steep, burned slope with sediment charged slopes and evidence of instability. Middle Fork Life and Risk of flooding, sediment delivery and Possible Major High Visited site with NRCS. Bridge – Lytle Safety, damage to homes and bridge. Several homes Inform County. Creek Property are located within the floodplain of the stream. Advise Engineering Staff of Residential Area Given the close proximity to the burn area, hazard. sediment loads and discharge will increase due to post-fire effects. (See modeled pour points.) South Fork Lytle Life and Risk of flooding and sedimentation, possible Possible Moderate Intermediate No treatment recommended. Creek/Bonita Safety safety concern. Site is located downstream of Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Flat Dispersed the burn area and will experience increased Recreation Sites discharge and sediment loads; however, modeled flows did not indicate flows would be significantly increased (pour point Middle Fk. Lytle Crk Bridge). Water quality may be decreased due to post-fire erosion upstream. City of Fontana Property, Risks of sedimentation, ash, and water quality Likely Moderate High Consult and inform agency of Water District on Municipal degradation. Not at risk of flooding as a result risk. Lytle Creek Water supply of the fire. (Intake Facility) Lytle Creek Life and Risk of minor flooding and sedimentation for Likely Major Very High Recommend working with the Recreation Safety, three of the recreation residences (#52, #50, County for erosion control and Residences Property #48). Rec cabins are located at the base of FS staff for clearance on ground short, steep, sediment charged, burned slopes disturbing activities. that direct runoff towards the cabins (swales). Remaining recreation residences not at risk. Road 2N53 Property Risk of road erosion, rock fall, loss of water Likely Major Very High Inform FS Engineering Staff of Applewhite Rd. control, diversion potential, debris flow. Road concerns. Close road and add is partially located at the base of steep, additional drainage control sediment charged, burned slopes and climbs up structures. the steep burned hillside. Evidence of past debris flows at channel crossings. Lost Lake Day Resource Risk of sedimentation, loss of lake capacity, Possible Moderate Intermediate Recommend fencing and barrier Use Recreation OHV incursion and trampling induced erosion. to prevent OHV access and Site Site is located on flat terrain (see modeling manage recreational use of the discussion) and was determined not to be at site. risk of significant sedimentation or loss of lake capacity due to post-fire effects. Due to lack of vegetation, OHV incursion and trampling may increase erosion at site and prevent vegetation response. Road 3N49 Low Property Risk of flooding, debris flow, erosion, Very Likely Major Very High Consult with LADWP on closure Water Crossings sedimentation, road damage. Crossing across and adding drainage control Lone Pine Canyon is at risk of flooding (see structures. modeling, pour point) during storm events. This crossing also has sediment charged, burned swales draining to it. Swale drainage has been diverted to the crossing because of the road and other spur locations near the crossing. Second crossing is located upstream of pour point Railroad 2 (see modeling for Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss trends in expected flows/erosion). Site has evidence of past debris flows and high sediment bed loads. Crossing has diversion potential that would result in at least 100 feet of road damage. Site is at risk of debris flows and washout. Lone Pine Life and Risk of flooding, sedimentation, erosion, Likely Major Very High Recommend coordination with Canyon Private Safety, property damage, and water quality impacts NRCS. Property and Property from burned structures. See discussion of post- Inform County of hazmat Residences fire hazards to structures on alluvial fans and concerns. drainages below burned slopes in modeling sections. See discussion of hazmat effects to water quality from burned structures. Lone Pine Property Risk of flooding, stream migration, Very Likely Major Very High Consult with SB County Public Canyon Road sedimentation, erosion. Loss of Access. There Works and Low Water are several low water crossings that are at risk Crossings of flooding and transporting large sediment bedloads. Crossings may become impassible during storm events due to post-fire runoff and erosion. Highway 2 Property Risk of Flooding, sedimentation, Highway Possible Major High Consult with Caltrans. Culverts east of damage. The basin has a flat area that could Addressing the gully would Wrightwood, CA provide sediment storage; however, there is a potentially address the OHV gully downslope that would drain directly onto access as well. Gully is used for the highway. There is a perched culvert OHV access. intended to drain the basin, but the gully is lower than the culvert inlet. See modeled pour point HWY 2 for estimates on discharge/sediment. Burned slopes in the area are sediment charged. Additionally, there is illegal OHV use/access of the site that could increase erosion potential and slope instability. Community of Property Risk of flooding. Site visit determined Unlikely Minor Low Not at risk. No treatment. Wrightwood, CA neighborhood is not at risk. Highway 138 and Property Risk of flooding, sediment, plugged culverts, Possible Major High Consult with Caltrans Culverts (East erosion, Highway impacts. Two main stem side to Cajon culverts were observed. Both have trash racks Pass) and large capacity to pass flows. One has sediment storage capacity, the other does not. The modeled pour point HWY 138 Xing 1 has erosion around the culvert inlet. Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Horse Thief Life and Potential risk of flooding and property damage. Unlikely Major Intermediate No treatment recommended. Canyon Private Safety, Field visit verified no risk to Horse Thief Property - Cajon Property community from post-fire effects. Burned area Pass Hwy 138 has flatter terrain and lower SBS, very little burned acreage. OHV incursion is an existing issue. Cajon Junction Property Basin above 1-15 culvert drains across side Unlikely Major Intermediate Consult with Caltrans Culverts I-15 road (lacks culvert) and leads to I-15 culvert through area with easily eroded material/existing gullies. Burned basin above has significant material that could be mobilized due to post-fire effects. Culverts under I- Property, Risk of plugged culverts and flooding onto Likely Major Very High Consult with Caltrans. 15 Life and highway. Safety Road near burned Life and Risk of flooding and sedimentation. Burned Likely Major Very High Consult with Caltrans. McDonalds/Gas Safety, basin drains to road that has no culvert. Burned Station (Pour Property basin above has significant material that could point Cajon be mobilized due to post-fire effects Drainage Junction) leads to I-15 culvert through area with easily eroded material/existing gullies. Mormon Rocks Property Risk of flooding and sedimentation. Burned Possible Moderate Intermediate Consult with Engineering Staff. Fire Station slopes are steep and have sediment charged Enhance berm to protect station swales/drainages. Small ditch and berm that from increased sediment protect Fire Station from runoff are insufficient delivery. Increase capacity of in size for post-fire discharge and erosion. drainage ditch. Clear out culvert. Small ditch is filled in and drains to plugged culvert. Highway 138 Property Risk of flooding, erosion, sedimentation,, Very Likely Major Very High Consult with Caltrans Culverts Cajon Highway damage. Drainages are expected to Canyon experience increased post-fire flows and sediment delivery (see modeling). Braided channel systems. Private Property Life and Risk of flooding, sedimentation, erosion, Likely Moderate High Recommend coordination with and Residences Safety, property damage, and water quality impacts NRCS. in upper Cajon Property from burned structures. See discussion of post- Inform County of hazmat Canyon fire hazards to structures on alluvial fans and concerns. drainages below burned slopes in modeling sections. See discussion of hazmat effects to water quality from burned structures. Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss FS Road 3N25 Property Risk of flooding, erosion, sedimentation, and Likely Major Very High Consult with Engineering Staff. and 3N35A Low road damage. Drainage is a braided channel Close road. Add drainage control Water Crossing that will experience increased post-fire flows structures to disperse road runoff. and sediment delivery. FS Road 3N24 Resources Threat to soil productivity and soil erosion, Very Likely Moderate Very High Install barriers and increase OHV Area to I- expansion of unauthorized OHV trails. Burned patrols to manage unauthorized 15 and open areas are now accessible to increased use. burned areas unauthorized OHV access that will increase erosion and sedimentation. Union Pacific Life and Risk of flooding, major property damage, Very Likely Major Very High Consult UP and BNSF and BNSF Safety, debris flows, rock fall, loss of commerce. Railways Property, Railways are located downstream of steep, Infrastructure Commerce burned, sediment charged drainages with a and Culverts history of instability and debris flows. Several sites are at very high risk of damage. PCT Railroad Life and Risk of flooding, and property damage. Hikers Likely Major Very High Advise Local PCT group. Underpass Safety, cross railway through a large culvert that is Signage of potential danger to (crossing through Property expected to experience increases in post-fire hikers. Site will need post-storm culvert) discharge and sediment (modeled pour point). trail maintenance. Trail at that site is located in a wash and below another tributary. During a storm, hikers would be at risk. Trail will washout. Keenbrook Life and Risk of flooding and property damage, debris Very Likely Major Very High Work with adjacent landowner Debris Basin and Safety, flows, erosion. Steep, burned, sediment (half of the dam and basin are not Spillway Property charged slopes prone to debris flows drain to on FS land). Coordinate and the basin. One side of the basin could be work with railroad companies to compromised by hillslope drainage and current develop solution. Further channel alignment. Spillway is being coordination between agencies undermined. Drains to undersized culvert needed to develop plan. below railway. Site will experience significant Recommend dam enhancement. increases in sediment and discharge (pour point Railroad 4). Keenbrook well Life and Risk of individual falling into exposed dam. Possible Major High Replace dam cover. (Or address Safety well during Keenbrook debris basin work). Railway Access Life and Flooding, debris flows, rock fall hazard. Steep, Very Likely Major Very High Consult with Engineering staff Road, Cajon Safety, burned, sediment charged slopes prone to and interagency coordination Wash and Blue Property debris flows drain to road. Upslope roads need with railroad agencies. Cut, 2N89 drainage control structures to prevent cascading effects of concentrated flow and increased post-fire erosion and discharge. Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Cajon Boulevard Life and Rock fall, sedimentation, minor flooding. Very Likely Major Very High Consult with SB County Public (Highway 66) Safety, Burned areas upslope may contribute increased Works Property discharge and sediment to roads below. Steep, burned slopes may produce rock fall. Heritage Sites (3) Resources Low threat of flooding. Sites are located in Possible Minor Low No treatment recommended. Lone Pine various places but away from main drainages. Canyon Sites may experience some sedimentation and flooding due to post-fire effects. Upper Lytle Property Flooding and debris flows, high rock fall Very Likely Moderate Very High Consult with Engineering Staff. Canyon Road hazard. 3N06 has significant rock fall hazard Address diversion potential of 3N06 and 3N33 from burned slopes. Steep, burned, sediment North Fork Lytle Creek down charged slopes prone to debris flows drain to 3N06. Add additional drainage road both roads. 3N33 is near a flat area that control structures on 3N33. Close will provide some sediment storage. both roads. Burned Resources, Hazmat refuse migration to Forest lands and Very Likely Moderate Very High Consult with SB County residences, Life and degradation of water quality. Several structures outbuildings, etc. Safety and other property were burned by the fire and now pose threats to water quality. Some of the burned items/structures were located in floodplains, channels, or on slopes that could deliver hazmat to channels. Some local residence use surface water for domestic use. See discussion on hazmat. LADWP Power Property Slope erosion hazard to towers from runoff and Likely Major Very High Consult with LADWP Towers, Cajon increased erosion. Some towers are located in Canyon areas that could be undermined by increased post-fire runoff. SCE Power line Property At risk of erosion and debris flows. Some Likely Major Very High Consult with SCE. poles and access locations of poles are near channels or roads drainages downstream of burned areas. Access roads are at risk of flooding, erosion, and damage. Applewhite Life and Possible flooding and sedimentation if culvert Likely Major Very High Close lower section of picnic Picnic Area (FS) Safety, upstream plugs. Potential cascading effects of area at crossing outlet. Property post-fire increases in sediment and discharge. There are two upstream culverts that have potential to plug. If culverts plug, sediment and water would be diverted and flow through the lower third of the picnic area. See model results at pour point Sheep Creek and Lytle Cr Rd Xing. Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Mountain Lakes Life and High potential for debris flows, flooding, Very Likely Major Very High Recommend cooperation with (Gate) Resort in Safety, sedimentation. Edge of resort area is located at NRCS. Lytle Creek Property the base of steep, burned slopes with sediment Recommend creating system to (Glen Ranch) charged drainages and swales. Slopes have clean out vertical drains within evidence of instability and history of debris the campground area. flows. Poses a safety threat to anyone at the Recommend fixing breached base of the slopes. Increased sediment could sediment berm designed to catch pose a threat to infrastructure and storm flow. drainage system. Currently, there are several Recommend closure of campsites locations flows could be diverted down roads. and areas nearest the burn area. Post-fire flows/sediment can plug the existing Recommend removal of drainage system, which is primarily an transportable structures away underground storm drainage system. Storm from the base of burned slopes. drains lead directly to the lake. Lake will Recommend private property experience increased turbidity and owner consult with engineer to sedimentation. Grate at the culvert outlet has upgrade/manage drainage system existing sediment plug and may be susceptible to handle post-fire to plugging with post-fire sediment. This flows/sediment. would cause the drainage system to back up. Small bridge at the outlet of the large culvert that drains to the lake is at risk (only has 6 inches of clearance for flow). Lytle Creek Road Life and Debris flows to crossing possible, hazard to Very Likely Major Very High Consult Engineering Staff. Post – Low Water Safety, vehicles. Crossing is located just over a berm. signs of potential hazards. Close Xing above Property If crossing floods or has sedimentation due to portion of road. Recreation post-fire effects, drivers will not see hazard Residences with enough time to stop. Berm was constructed to protect downstream community from debris flows. Basin draining to crossing has history of debris flows. Low Water Life and Crossing will not likely be affected by small Unlikely Major Intermediate Consult with SB County Public Crossing Lower Safety, area of fire effect in relation to the overall size works Lytle Creek Road Property of the watershed, is known to be affected by large watershed scale floods. Additionally, the crossing is located several miles downstream.
Large culvert I- Property Large 8 x 12 culvert ¾ plugged with sediment. Likely Major Very High Consult with Caltrans 15, above Cajon Junction on west side Probability of Magnitude of Risk Treatment Assessment Values at Observations Damage or Consequences Recommendation Site Risk Loss Kinder-Morgan Property Potential for pipeline damage in drainages Likely Major Very High Consult with Kinder-Morgan. Petroleum from flooding, debris flows, incision. Actual Pipelines location of lines is unknown. However, if buried lines cross drainages or areas prone to debris flows, lines could be uncovered or compromised. Southern Property Potential for pipeline damage in drainages Likely Major Very High Consult with Southern California California Gas from flooding, debris flows, incision. Actual Gas location of lines is unknown. However, if buried lines cross drainages or areas prone to debris flows, lines could be uncovered or compromised ATT Fiber optic Property Potential for pipeline damage in drainages Likely Major Very High Consult with ATT underground line from flooding, debris flows, incision. Actual location of lines is unknown. However, if buried lines cross drainages or areas prone to debris flows, lines could be uncovered or compromised Domestic Water Life and Risk of sediment, ash, hazmat runoff to water Very Likely Moderate High Consult with RWQCB. Use Safety quality. House (Blue Cut) Property. Flooding, sediment, erosion, and debris flow. Likely Moderate High Recommend to NRCS Life and Structure is located near upstream road Safety crossing in pour point Railroad 3. Area is prone to debris flows, and will experience increased post-fire flows and erosion (see modeling). Structure is located on a steep embankment above the stream channel. Post- fire flows/debris flows could cause embankment erosion.
B. MODELING FOR POST-FIRE EFFECTS
1. Hydrologic Modeling
a) Hydrologic Model and Design Storm Description
The analysis for pre- and post- fire hydrologic response and probability of flows is based on the probability of a 2-year storm occurring in the fire area. The 2-year design storm has a 50% chance of occurring in any given year, and a 97% chance of occurring in the next five years. Conversely, there is a 3% chance that the 2 year storm event will not occur in the next 5 years (during the recovery period). A damaging storm expected to occur within the fire burned area is a short duration, high intensity storm, such as the 2 year recurrence interval, 30 minute duration storm with approximately 0.54 inches of precipitation (NOAA, 2014).
It is important to note that any VAR found to be at risk during the 2 year event will still be at risk during greater events. Several locations within the analyzed area have an inherent risk of flooding and debris flows in greater recurrence interval storms. We have included information for recurrence interval storms for both ~5 year and ~10 year peak flows and erosion rates.
In analyzing the change in watershed response, the pre-fire discharge must be calculated and estimated. The pre-fire design flow is the flow responsible for forming present day channel conditions and flows used to estimate proper performance of culverts and other drainage structures. Pre-fire design flows assume pre-fire infiltration and ground cover conditions.
To execute the models, catchments were delineated above specific pour points. A pour point is the outlet of a catchment through which all runoff in the catchment passes through. Several pour points of different sizes were established across the burned area to capture the estimated increase in hydrologic response the fire might produce (Appendix A, Maps 1, 2, 3, 4). These catchments and pour points were selected to represent the general characteristics of the potential post-fire affects on hydrologic processes, erosion, and sediment delivery. Some pour points were selected based on locations of specific VARs; however, not all VAR locations were modeled. The modeled locations and mapped subwatersheds DO NOT represent the only locations at risk of altered hydrologic processes, and increased erosion and sediment delivery. Results of the modeling are intended to reflect general trends in the burned area and to highlight potential risks across the broader area for further analysis (example: railroad pour points) or for the specific VAR selected (example: specific T&E wildlife concern). More analysis is required for a detailed map of all specific locations that may be at risk from post-fire effects.
Two models were used to determine pre- and post-fire discharges in the assessment watersheds. The primary model used for the burned area was the model designed by Rowe, Countryman, and Storey (RCS), 1949. Kinoshita, Hogue, and Napper, 2014 validated continued use and applicability of this model for Southern California. The model designed by RCS provides data for pre- and post-fire discharges and erosion rates in southern California watersheds. Individual rates for various subwatersheds were developed over long observation periods. The analysis in this report is based on the information in Tables 63, 63, 65, and 98 (RCS, 1949). On-the-ground observations were integrated into the model to account for local basin and burn pattern characteristics. Adjustments to the model were based on: percent of low soil burn severity exhibiting high water repellency, terrain, location of low SBS on the landscape in relation to high and moderate SBS, slope, existing landslides, and soil characteristics.
Hydrologic design information for the RCS hydrologic model is based on the 24 hour duration storm, Table 6. The 2 year, 24 hour duration storm anticipated for these subwatersheds is 6.03 inches (NOAA, 2014). However, although the RCS model is based on the 24 hour duration storm, the anticipated storm expected to occur within the fire burned area that could produce damaging post-fire effects is a short duration, high intensity storm (used as the design storm), Table 7 (NOAA, personal communication). Characteristics of the design storm are listed in Table 7 (Appendix B).
Table 6: Hydrologic Design Factors for RCS
A. Estimated Vegetative Recovery Period 5-10 B. Design Chance of Success 95% C. Equivalent Design Recurrence Interval 2 years D. Design Storm Duration 24 hours E. Design Storm Magnitude 6.03 inches G. Estimated Reduction in Infiltration 57% across fire Ga. Estimated Reduction in Infiltration 25% of acres categorized as Low SBS
Table 7: Hydrologic Design Factors for Design Storm
A. Estimated Vegetative Recovery Period 3 to 10 years 3 to 10 years 3 to 10 years B. Design Chance of Success 80% 75% 70% C. Equivalent Design Recurrence Interval 2-yr and 5-yr 5-yr 10-yr D. Design Storm Duration 30 min. 2 hrs. 6 hrs. E. Design Storm Magnitude 0.54 in 2.05 in. 4.88 in. F. Design Flow 83.2 cfs/sq.mi. 161 cfs/sq.mi. 250 cfs/sq.mi. G. Estimated Reduction in Infiltration 57% 57% 57% H. Adjusted Design Flow 159 cfs/sq.mi. 308 cfs/sq.mi. 478 cfs/sq.mi.
A second model was used to determine pre- and post-fire discharges in areas not covered by the RCS model. This model was developed by Waananen and Crippen (1977) was also used to predict pre-fire discharges at different recurrence intervals. Waananen and Crippen developed regional equations that estimate discharge of various return intervals based on watershed characteristics. The adjusted post-fire peak flows are calculated using the same relationships as design flow; however, runoff response is estimated by assuming an increased runoff commensurate with soil burn severity in terms of recurrence interval. A modifier is determined based on percent runoff increase and percent moderate and high SBS in the watershed. The modifier is applied to the peak flows estimated by regional equations. For Southern California, the primary characteristics that affect regional equations are precipitation and basin size. The USGS StreamStats website was used to gather the data for these areas (example: Manzanita Wash).
Bulking of Flows: Following fire events, discharge may be bulked due to the increase in sediment and erosion, which may occur following fire as a result of debris flows/torrents. Following the 2003 Cedar Fire on the Cleveland National Forest, non-bulked results calculated using Rowe, Countryman and Storey were compared to a modified rational equation model which considered bulked flow using the U.S. Army Corps of Engineers Los Angeles district method for prediction of debris yield (2000). This comparison found that predicted bulked flows were 2.14 times larger than unbulked flows. Post-fire flow estimates should be multiplied by 2.14 to approximate bulked flows. This added volume is NOT reflected in the modeling results.
b) Hydrologic Modeling Results
The increase in peak flows is most applicable during the first to second year of recovery, as hydrologic response will decrease in subsequent years as vegetation re-establishes. Drought conditions in the first year of recovery can delay vegetation response, hence delay recovery to pre-fire conditions. The results of the hydrologic analysis find that most of the subwatersheds that contain burned area will respond to the 2 year recurrence interval storm with greater runoff, erosion, and sediment delivery to streams than typically seen in a 2 year recurrence interval storm (Table 8, Appendix A, Maps 1, 2, 3, 4, and Appendix C). The modeled subwatersheds are representative of the various catchments draining to the pour points and within similar catchments in the fire burned area; however, the pour points DO NOT represent the ONLY locations at risk. The models represent general trends in increases of runoff that will be observed across and below the fire affected area.
Modeling results of small catchments containing large percentages of moderate and high soil burn severity and steep slopes exhibit the greatest increases in peak flow, erosion, and sediment delivery, such as Railroad catchments 2-6. Estimated post-fire runoff in a 2 year design storm could resemble runoff similar to peak flow discharges with recurrence intervals of 6 to 10 years (vs. 2 year recurrence interval peak flow). The 5 year design storm in these catchments are estimated to produce discharges similar to a 90 to 100 year storm. These catchments contain very high percentages of high SBS, steep slopes, and on- the-ground observations of sediment charged channels. The combination of these characteristics pose a very high risk to these areas. Again, the modeled catchments are NOT the only locations at risk but represent the trends that can be expected in catchments with similar characteristics.
Figure 2. Potential for cascading effects and drainage control failures from combination of land activities.
Similar concerns are applicable to the recreation residences and recreation areas in Lytle creek (modeled by pour points Lytle Resort 1&2). In these small, steep burned basins, estimated post-fire runoff in a 2 year design storm could resemble runoff similar to peak flow discharges with recurrence intervals of 5 years (vs. 2 year recurrence interval peak flow). The primary concern for these sites is related to not only the close proximity of to the burn area but the combination of increased runoff, erosion and sediment delivery (discussed in the erosion section), and on-the-ground field observations of sediment charged channels. Some of these hillslopes and swales do not normally have overland flow (pre-fire conditions). With post-fire effects on increased discharge, there may be formation of channels and drainage in areas where water has not flowed in pre-fire conditions. Field surveys identified some areas had inadequate drainage control structures or lacked drainage control structures altogether, leaving the sites ill prepared to handle increased post-fire discharge and overland flow.
Figure 3. Infrastructure on private property downslope of steep burned drainages are at risk of increased post-fire discharge, debris flow, rockfall, erosion, and sedimentation.
Infrastructure, roads, homes, communities, and crossings located along stream channels, on alluvial fans, or near swales downstream of the fire burn area will be at higher risk from the estimated increases in discharge. These areas are most likely to flood because of proximity to drainage paths. Several pour points were selected to model low-water crossings and alluvial fans (see maps for pour point locations and Table 8 for results). All locations are expected to experience increased flows.
Stream crossings (represented by pour point modeling of: Lone Pine Canyon at LADWP Rd Xing; Sheep Creek and Lytle Cr Rd Xing; and Pioneer & Hwy 138 Xing) are subject to flooding and may be hazardous during storm events. (See erosion section on plugging of culverts due to increased post-fire sediment.) This is especially true for low water crossings. Modeled estimates of flow indicate the 2 year design storm may result in peak flows similar to a 4 year peak flow. The 5 year design storm is expected to produce runoff similar to a 12 year peak flow. On-the-ground observations indicated most stream channels in the fire burn area are braided channel systems subject to migration and have high sediment loads. It is expected that roads within the burn perimeter that have exhibited pre-fire erosion and flooding hazards will have increased risk of erosion and flooding due to the fire. Again, the modeled crossings are NOT the only locations at risk but results represent the trends that can be expected at other crossings with similar characteristics downstream of the fire burn area.
Figure 4: Stream crossings draining basins with high and moderate SBS are at risk of flooding, increased sedimentation, and plugging. Plugged culverts can divert water and sediment to other locations not equipped to handle runoff. Diverted flow has potential to cause gullying, property damage, and risks to life and safety. Low water crossings could be dangerous for drivers to cross during post-fire storm events.
Drainage paths on alluvial fans are subject to migration, so areas that have not previously experienced concentrated runoff or have defined channels may develop them. For example, modeled results of pour points at the West Cajon Valley wash, Cajon Wash 2, and Lone Pine Canyon indicate increased hydrologic response below steep, burned slopes onto alluvial fans containing downslope infrastructures and homes. Peak flows in the 2 year design storm will respond with peak flows similar to 5 to 10 year recurrence interval peak flows. The 5 year design storm is expected to result in peak flows similar to 15 to 25 year recurrence interval peak flows. (Increased sediment also needs to be considered and is discussed in the erosion modeling section). Some of these communities have wide, braided channels leading from the steep slopes in the burned area down into the community. In some cases, once drainage channels have reached community boundaries, the channels have been altered and/or dissipate into vegetation. With the fire effects on hydrologic response, these areas are expected to experience redefining of the channel, potentially migration of the channel, runoff in areas previously not experiencing concentrated runoff, erosion, or sedimentation, and increased erosion/flooding in areas already experiencing flooding and erosion pre-fire. Again, the modeled catchments are NOT the only locations at risk but results represent the trends that can be expected in catchments and areas with similar characteristics.
Figure 6: Several communities are located on alluvial fans below steep, burned slopes. The headwaters of the burned slopes are inherently unstable with evidence of active pre-fire mass wasting and high erosion rates. Increased post-fire hillslope instability and changes to current drainage patterns in these areas is expected putting the communities at risk of post-fire effects.
Buried infrastructure (such as buried transmission lines) could be at risk of exposure from increased flows that scour out swales, channels, and drainages (where infrastructure crosses these features). (Risks from debris flows are discussed in the debris flow section of this report.) In areas where transmission lines or pipes cross above these features above ground, there may be risks associated from the combination of increased flows, post-fire sediment increases, and woody debris. It is recommended that a closer analysis is completed on buried infrastructure as the FS did not receive sufficient information to analyze risks to these features.
Pour points selected specifically for concerns to wildlife habitat include Sheep Creek Wildlife Habitat, Lost Lake, and HWY 138 Xing 1. Expected fire effects for hydrologic response in Sheep Creek Wildlife Habitat pour point is increased flows (2 year event will respond like a 5 year event). This site is located in a steeper, transport section of the stream channel and will most likely experience incision and down- cutting; however, most of the riparian area did not burn and will help minimize erosion potential and effects from increased flows.
Lost Lake is located in flat terrain, with soils that have high infiltration rates, and a small catchment area. The hydrologic response is expected to be minimal, with only a slight increase in discharge.
Habitat downstream of HWY 138 Xing 1 pour point will experience increases in flooding potential (2 year design storm runoff will respond like a 4 year peak flow). This section of the channel is wider, braided, and more of a depositional area. The stream channel may experience some post-fire effects such as channel migration, filling in of pools, and erosion; however, riparian vegetation is expected to respond/re-establish quickly, which will help stabilize the area. Additionally, leading to the habitat in this area are three tributaries, one of which (modeled) has a large depositional area upstream of the HWY 138 crossing. This depositional area will help minimize post-fire hydrologic and sedimentation effects. TABLE 8: Comparison of Pre and Post-Fire Discharge at Selected Sites (pour points) intended to provide general trends of flooding risk. Percent increase in discharge represents the percent above normal. All pour points exhibit increases in flows compared to pre-fire discharge.
Post-Fire Discharge % Increase in Pre-Fire Discharge Post-Fire Discharge Compared to Pre-Fire Discharge* Pour Point Discharge ~Q2 Q5-6 Q10-12 ~Q2 Q5-6 Q10-12 ~Q2 Q5-6 ~Q10-12 Q2 Cajon Junction (near Mcdonalds) 6 9 13 10 16 22 ~Q10 ~Q25 ~Q80 67% Cajon Wash 1 (Below fire area) 3,130 5,376 7,819 4,354 7,096 10,045 ~Q4 ~Q11 ~Q26 39% Cajon Wash 2 (above community) 9 16 22 18 27 37 ~Q8 ~Q25 ~Q80 100% Hwy 138 Xing 1 (above wildlife 46 77 110 68 109 149 ~Q4 ~Q12 ~Q28 48% habitat) Hwy 2 (basin near HWY) 7 13 19 11 18 24 ~Q4 ~Q9 ~Q20 57% Lone Pine Canyon (hillside wash) 3 6 10 8 14 21 ~Q10 ~Q25 ~Q75 167% LonePineCanyon at LADWP Rd Xing 407 772 1,270 625 1,092 1,729 ~Q4 ~Q10 ~Q25 54% Lost Lake 2 4 7 3 6 9 ~Q3 ~Q8 ~Q25 50% Lytle Creek above community 875 1,754 2,823 900 1,795 2,880 ~Q2 ~Q5 ~Q10 3% Lytle Resort 1 (swale) 1 2 3 2 3 4 ~Q5 ~Q12 ~Q40 100% Lytle Resort 2 (swale) 0 1 1 1 1 2 ~Q5 ~Q12 ~Q40 150% Manzanita Wash 10 57 143 12 68 171 ~Q3 ~Q6 ~Q12 20% Middle Fk Lytle Cr Bridge 981 1,966 3,163 1,033 2,050 3,282 ~Q3 ~Q6 ~Q13 5% PCT at RR Culvert Xing 70 119 169 117 184 251 ~Q5 ~Q20 ~Q40 67% Pioneer & Hwy 138 Xing 126 214 304 201 317 435 ~Q4 ~Q13 ~Q30 60% Railroad1 19 36 59 43 72 111 ~Q8 ~Q20 ~Q50 126% Railroad2 13 25 41 34 55 84 ~Q10 ~Q24 ~Q80 162% Railroad3 6 11 18 15 24 37 ~Q10 ~Q25 ~Q80 150% Railroad4 38 68 98 109 167 218 ~Q13 ~Q90 >Q100 187% Railroad5 8 14 21 23 35 46 ~Q15 ~Q100 >Q100 188% Railroad6 3 6 8 9 14 18 ~Q25 ~Q100 >Q100 200% Railroad7 15 25 35 25 39 53 ~Q5 ~Q20 ~Q50 67% Sheep Creek and Lytle Cr Rd Xing 23 46 73 39 71 110 ~Q4 ~Q12 ~Q30 70% Sheep Creek Wildlife Habitat 9 17 29 16 27 43 ~Q5 ~Q12 ~Q26 78% West Cajon Valley wash 37 63 89 60 94 129 ~Q5 ~Q15 ~Q40 62% *All percentages are increases above normal. 2. Erosion Modeling
(For information on debris flows and debris flow hazards, see separate discussion specifically about debris flows and slope instability inherent to the burn area.).
a) Erosion Model Description
Three methods were utilized in estimating erosion throughout the fire area (not including debris flows modeling). The Blue Cut Fire Soils Report discusses the ERMiT and Erosion Hazard Rating (EHR) modeling methods and description of findings. Additionally, annual erosion rates can be determined using Rowe, Countryman and Storey (RCS), 1949. In RCS, 1949, erosion rates post-fire are found to be proportional to “acres burned”. As with the hydrologic modeling, “acres burned” can be adjusted based on several site specific characteristics. Tables 9 and 10 display estimates of increased erosion modeled from the three methods following the fire. These values can be used to estimate general trends across the burn area. Additionally, on-the-ground surveys observed sediment charged swales, channels, and hillslopes. This sediment could be readily mobilized given the increase in runoff potential and lack of vegetative cover/stabilization. Sediment laden areas will contribute to the increase risk of erosion and sedimentation from the burned area to downslope areas.
b) Erosion Model Results
All the modeled subwatersheds will experience increases in erosion with the greatest increases occurring in subwatersheds with the most burned acres and the steepest slopes. Subwatersheds with a large percentage of unburned acres or flatter terrain exhibit less of an increase; however, areas within these subwatersheds that are in close proximity to the burn may still have increased sediment beyond that which resulted in modeling. For example, campsites, recreation residences, and private land adjacent to burned slopes will experience increased sediment delivery from burned slopes despite the results modeled for the larger watershed (such as pour points: Middle Fk Lytle Cr Bridge; and Lytle Creek). Some smaller basins (adjacent to infrastructure in Lytle Creek) were modeled to establish estimates of sediment delivery trends for short, steep, burned slopes in the area. Short steep slopes in the area are expected to deliver ~1300% of normal sediment delivery (pour points Lytle Resort 1 & 2). As with other areas, several of these steep slopes were observed to have sediment charged channels, swales, and hillsides that will contribute to the sediment delivery risk.
Some areas (homes, infrastructure, and recreation sites) along the creek or in the floodplain downstream of the burn area are susceptible to post-fire effects although they may not be located IN the burn perimeter. This also applies to communities and infrastructure located on alluvial fans below the burn area (example pour points: Lone Pine Canyon; and Cajon Wash 2). Post-fire effects of increased sediment and increased flows can alter existing channel characteristics such as filling in of pools or other depositional areas, erosion of banks, braiding of channels, migration of existing channel locations, down-cutting of channels in transport sections, sedimentation, etc.. Eroded material off the burn area may contain woody debris that can become lodged, trap sediment, and alter flow patterns or plug culverts. Plugging of culverts can divert water and sediment down roads or into locations it normally does not flow. Channel diversion can result in catastrophic road failure and flooding/sedimentation in areas where flow and sediment has been diverted. Runoff channels on alluvial fans are subject to migration naturally and with the additional increase in flow and sediment, areas below the burn area can expect changes to existing runoff patterns (as described above).
TABLE 9: Comparison of Pre and Post-Fire Erosion at Selected Sites (pour points) intended to provide general trends of post-fire erosion potential.
Erosion in Cubic Yards Per Year (RCS model) Pour Point Erosion Hazard Rating Pre-Fire Post-Fire % Increase Cajon Junction (near Mcdonalds) 185 3,859 1986% Very High Cajon Wash 1 (Below fire area) 108,749 1,050,385 866% -- Cajon Wash 2 (above community) 307 6,585 2045% Very High Hwy 138 Xing 1 (above wildlife habitat) 2,323 36,212 1459% High Hwy 2 (basin near HWY) 138 1,364 888% Very High Lone Pine Canyon (hillside wash) 144 4,301 2887% Very High LonePineCanyon at LADWP Rd Xing 18,488 196,457 963% Very High* Lost Lake 129 2,080 1512% Low Lytle Creek above community 49,396 76,632 55% Very High* Lytle Resort 1 (swale) 53 745 1306% Very High Lytle Resort 2 (swale) 14 194 1286% Very High Manzanita Wash ------Moderate Middle Fk Lytle Cr Bridge 55,359 111,609 102% Very High* PCT at RR Culvert Xing 2,342 37,634 1507% Very High Pioneer & Hwy 138 Xing 4,206 60,758 1345% High Railroad1 850 20,720 2338% Very High Railroad2 584 17,437 2886% Very High Railroad3 258 7,686 2879% Very High Railroad4 1,333 29,072 2081% Very High Railroad5 281 6,119 2078% Very High Railroad6 72 1,569 2079% Very High Railroad7 486 8,181 1583% High Sheep Creek and Lytle Cr Rd Xing 1,282 18,590 1350% Very High Sheep Creek Wildlife Habitat 408 5,998 1370% Very High West Cajon Valley wash 1,237 18,225 1373% Very High
TABLE 10: Comparison of Pre and Post-Fire Erosion at Selected Railroad crossings intended to provide general trends of post-fire erosion potential off slopes above the railroad. Table displays results from three models. RCS estimates annual erosion. ERMiT estimates erosion given a specific storm event.
Erosion in Tons Per Year (RCS) Erosion Tons of Sediment per Event (ERMiT) Pour Point Hazard Pre-Fire Post-Fire % Increase Rating 2 year RI 5 year RI 10 year RI Railroad1 1,530 37,297 2338% Very High 5,019 14,072 20,094 Railroad2 1,051 31,387 2886% Very High 5,828 15,984 23,456 Railroad3 465 13,834 2875% Very High 2,748 8,264 12,239 Railroad4 2,400 52,330 2080% Very High 6,826 20,023 29,828 Railroad5 506 11,014 2077% Very High 1,642 4,474 6,534 Railroad6 130 2,825 2073% Very High 685 2,002 3,000 Railroad7 874 14,725 1585% High 1,502 3,904 5,498
Some watersheds draining to several VARs, such as the modeled Railroad 1-7 pour points, exhibit increases of sediment from approximately 2,000%-3,000% of normal. These modeled subwatersheds are representative of the various catchments draining to the railroad crossings below fire burned slopes; however, they DO NOT represent the ONLY locations at risk. The models represent general trends that will be observed across the area. Table 10 displays comparisons of the three erosion models. All three models indicate high erosion and sediment delivery off these slopes and drainages.
Figure 7: Debris flow prone headwaters and drainages that are sediment charged pose risks to several VARs located downslope below the burn area. Photo was taken from a railroad crossing looking upstream.
Figure 8: Several crossings below major roads and highways are at risk of plugging. The culvert in this photo is a >10 ft diameter culvert (not a bottomless arch) that is more than 2/3 plugged. Increased sediment delivery could cause plugging of the culvert, resulting in road failure and flooding.
Pour points selected specifically for concerns to wildlife habitat include Sheep Creek Wildlife Habitat, Lost Lake, and HWY 138 Xing 1. Expected post-fire erosion potential in Sheep Creek Wildlife Habitat pour point is an increase of 1370% and was rated as a Very High EHR. This site is located in a steeper, transport section of the stream channel and will most likely experience incision and down-cutting; however, most of the riparian area did not burn and will help minimize erosion potential and effects from increased flows.
Lost Lake is located in flat terrain, with soils that have high infiltration rates, and a small catchment area. Based on site specific field observations, the RCS erosion modeling for this site over-estimates the increase in sediment delivery to Lost Lake. Erosion and sedimentation of the Lost Lake pour point modeled area will experience increases in sediment but not at the level RCS modeled. The EHR model rated this area as Low Erosion Hazard Rating, which is more applicable based on field observations. Because this site is a recreational area, there is potential for increased erosion due to trampling and soil disturbance (OHV and hikers) before vegetation can re-establish.
Habitat downstream of HWY 138 Xing 1 pour point will experience increases in sediment delivery (approximately 1500% increase and rated as High EHR). This section of the channel is wider, braided, and more of a depositional area. The stream channel may experience some post-fire effects that are related to increased flows and sediment delivery such as channel migration, filling in of pools, and erosion; however, riparian vegetation is expected to respond/re-establish quickly, which will help stabilize the area. Additionally, leading to the habitat in this area are three tributaries, one of which (modeled) has a large depositional area upstream of the HWY 138 crossing. This depositional area will help minimize post-fire hydrologic and sedimentation effects.
3. Debris Flow Modeling
The Blue Cut Fire occurred in a landscape characterized by debris flow and landslide processes, as indicated by alluvial fan deposits below steep slopes with visible relic and active headscarps. Debris flows can occur in any rock type, but are most common in metamorphic and sedimentary rocks. Debris flows can be initiated on slopes of 20° (36%) and greater. They can deliver quantities ranging between 100 – 1,000,000 cubic yards of rock, sediment and large woody material, depending on rainfall amounts, slope, and amount of unconsolidated soil, rock and sediment material available. Debris flows most commonly occur in burned areas within the 2-year span of time after the fire, in areas of moderate and high soil burn severity.
Debris flows, erosion, and peak stream flows were modeled for the Blue Cut Fire. The various models utilize different types of rain storm conditions. The damaging storm (selected design storm) expected to occur within the fire burned area is a short duration, high intensity storm, such as the 2 year recurrence interval, 30 minute duration storm (Table 7). The selected design storm in Table 7 was compared to post- fire debris flow observations and modeling conducted for Southern California by Cannon, Boldt, Laber, Kean and Staley, 2011. Based on this study, the design storm selected for the fire burn area is very likely to produce debris flows of a sizeable volume.
As described in the Hydrologic Modeling section, the RCS hydrologic model is based on a 24-hour duration rain event. The peak stream flow model results represent a predicted volume comprised principally by water and secondarily by sediment. The peak stream flows predicted by the RCS model do not include volumes of material that have the potential to be delivered by debris flows.
Debris flows are most likely to occur as a result of short duration, high-intensity rain storms; therefore, the USGS Debris Flow model calculated results for 15-minute storms. Debris flows can result in volumes of sediment, rock, organic material and water transported down slopes and stream channels that are orders of magnitude greater than the volumes of peak stream flows predicted by hydrologic models, such as the RCS model that was utilized by the Forest Service BAER Team. Debris flow likelihood, volume and the combined hazard of these was modeled by the U.S. Geological Survey for the Blue Cut Fire. Empirical spatial calculation was performed remotely by the USGS. Parameters of the model included soil burn severity, terrain, channel confinement, soil K factor, rain storm intensity and duration, and historical debris flow data. Floods, including sediment-laden flash floods are not predicted in the USGS debris flow model. Further information about the USGS debris flow modeling results are filed in the USDA Forest Service, Blue Cut Fire BAER electronic records.
USGS modeling results for debris flows as a result of the Blue Cut fire were generated remotely utilizing the soil burn severity map (field verified and adjusted by the BAER team); however, field observations of active landslides (0.25-10 acres each) in the Keenbrook, Blue Cut, and Lower Lytle Creek areas within Cajon Canyon, in the southernmost portion of the fire, were not accounted for in the USGS-generated debris flow model results. Field observations of watersheds on the west side of Cajon Canyon (labeled watersheds, Railroad 1-6) where high and moderate burn severity occurred, revealed soil and sediment accumulations around the base of stems of burned chaparral vegetation, due to a pre-fire closed-canopy, old-growth chaparral condition. This soil and sediment accumulation on hillslopes is readily available for mobilization in the first rain events after the fire. Field observations found that the USGS-debris flow model underestimates the likelihood, volume, and combined hazard of debris flows in the Keenbrook and Blue Cut areas in Cajon Canyon.
Based on field observations, Soil Erosion Hazard Rating (EHR) mapping as a product of the ERMiT model, more closely reflects the degree of hazard for debris flows to occur in modeled debris flow basins (Appendix D, Maps 1, 2, 3, 4). EHR and comparison of the design storm with the Southern California post-fire debris flow study (Cannon et.al, 2011) are expected to more adequately represent debris flow hazard potential. See Appendix D for maps displaying the Erosion Hazard Ratings for the fire area. Overall, there is a high risk of post-fire debris flows throughout several locations in the burned area, especially in areas that have evidence of active landslides and scarps.
Figure 8: Headwaters leading to Keenbrook dam have significant amounts of sediment that are expected to be mobilized in the design storm listed. Risk of erosion, increased discharge, and debris flows in these areas is expected to increase significantly due to post-fire effects.
Figure 9: Slopes have evidence of active and historic slope failures.
Figure 10: Debris flow prone headwaters and drainages that are sediment charged pose risks to several VARs located downslope or on alluvial fans below the burn area. Photo is of private property located on an alluvial fan adjacent to a drainage that has a history of debris flows. Basin drains to at least one road crossing, then two railroad crossings before reaching main drainage below. Potential for catastrophic, cascading failure is high.
Hillslope treatments were considered as a means of reducing the likelihood of debris flows, particularly for the watersheds with greatest effect to the railroads along Cajon Canyon. Scientific studies consistently show that hillslope treatments such as hydro-mulch, straw mulch, and wood/straw mulch are effective on burned slopes less than 60%. Watersheds were analyzed for suitability for hillslope treatments, with results showing that the slopes exceeded the steepness threshold for effective mulching. Scientific studies also show that certainty of success of mulch as effective erosion control is greatly reduced during high intensity rain events, which are the type of events expected to trigger a debris flow.
Hillslope treatments were ruled out by the FS BAER team based on the following factors: likelihood of short duration, high intensity rain events in the Blue Cut Fire area, lack of suitable slopes for effective hillslope treatment on National Forest lands, and the uncertainty of effectiveness of hillslope treatments.
4. Water Quality and Environmental Effects of Hazmat
a) Threats to Water Quality and Beneficial Uses of Water
Peak flow increases from the fire will also be bulked by ash, debris and other floatable and transportable material within stream channel areas of the fire. Temporary episodes of water quality degradation and fine siltation is likely during the first year after the fire to Cajon Canyon Creek and major tributaries. Less severe and localized water quality impacts to North Fork Lytle Creek below burned tributaries upstream and adjacent to the Lytle Creek residential area and downstream could occur. Beyond the first year, post-fire water quality impacts will be lessened as the burned watersheds recover. Beneficial uses listed in Tables 1 and 2 could experience temporary impacts post-fire.
b) Hazmat Release Potential from Burned Residential Refuse
The California Integrated Waste Management Board (CIWMB) has stated that ash and debris from residential structures consumed by wildfires may contain concentrated amounts of heavy metals, such as arsenic, barium, beryllium, copper, chromium, cadmium, lead and zinc (CIWMB, 2007). Further, according to the CIWMB, the occurrence of these metals in burned residential debris has been demonstrated in the “Assessment of Burned Debris Report for the Cedar and Paradise Fires, San Diego County, CA” dated December 2003. It is also known that asbestos remains are found in burned debris and poses a threat when disturbed and airborne. Common household products found in burned structures are usually present such as pesticides, fertilizers, paints and thinner, automobile products and other petroleum based products.
Up to 104 residences and outbuilding burned during the Blue Cut Fire. It is known that the fine debris of burned residential refuse contains toxic materials such as lead, mercury, arsenic and other metals, along with pesticides, petroleum products and other hazardous substances Without containment or removal of the refuse, there is a potential for off-site migration of hazardous materials to drainages caused by storm runoff, and soil and water contamination could result. Many of the ephemeral channels in the fire area could be impacted by residential refuse if not contained or removed before large storm events mobilize the waste. Several burned residences are located near drainages or in floodplains in braided channel systems. Forest lands downstream may be impacted. Reaches of surface water in Lower Cajon Creek may be contaminated if refuse is not contained or disposed from nearby burned buildings and from tributary sources upstream.
Figure 11: Photo of burned items and infrastructure that could pose risks to water quality if washed off site and into streams.
III. SUMMARY OF TREATMENTS AND MANAGEMENT RECOMMENDATIONS
A. EMERGENCY STABILIZATION TREATMENTS AND MANAGEMENT RECOMMENDATIONS
Watershed specialists identified and surveyed areas of concern containing values at risk (life and safety, property, and resources). Following field evaluations and modeling results, watershed specialists recommended the following treatments and actions to address risks from post-fire flooding, sedimentation, rockfall, and debris flows. See Table 5 for site specific treatment recommendations.
1. National Forest Jurisdiction Facilities, Roads and Trails
Applewhite Campground - Closure The Applewhite Campground is positioned in a very hazardous area with high rockfall, sedimentation and debris flow potential. The campground is located within the deposition zone of an alluvial fan below steep, moderately burned slopes, with loose rock and sediment likely to be delivered into the campground. Although there is a chain link fence near the base of the alluvial fan bordering the campground, this fence is not expected to provide adequate protection to campground users. The campground should be closed to protect life and safety during the vegetation recovery period after the fire. A 1 to 2-year closure is recommended with follow-up evaluation prior to re-opening.
Applewhite Picnic Area – Closure of Lower Half The lower, southeast portion of the Applewhite Picnic Area should be closed during the first 1-2 years of the vegetation recovery period after the fire, due to risk of flooding of Sheep Creek into the lower picnic area. There is high potential for a cascading effect of upstream culvert failure to cause flooding in the picnic area. The Applewhite Picnic Area should be closed east of the Sheep Creek Culvert, to both vehicle and pedestrian access.
Implement BAER Roads Treatments specified by Engineering The road drainage improvements and maintenance specified for roads are critical to protecting life and safety, property, and resources from the effects of increased runoff, sedimentation, and erosion as a result of the fire. Several roads have inadequate drainage control structures to handle the increased post-fire runoff and erosion. There is potential for loss of drainage control on several roads to contribute to cascading failures downslope and catastrophic gully formation. Additionally, several low-water crossings are expected to be at risk of debris flows, and increased sediment and discharge during storm events, increasing life and safety risks for road users. Other roads have increased potential for rockfall, especially in areas with steep cutslopes, bedrock outcrops, and scree slopes. Vegetation in these areas previously helped stabilize hillsides and outcrops; however, with the lack of vegetation, occurrence of rockfall is expected to increase and could result in catastrophic effects for road users.
Close and decommission unauthorized OHV routes Non-system OHV routes concentrate runoff, and this condition is exacerbated by the fire. Decommissioning unauthorized OHV routes will reduce the risk of flooding, erosion and sedimentation.
Recap burned well at Keenbrook dam Well near Keenbrook dam was burned, removing the cap and posing a safety hazard. Well needs to be re-capped or decommissioned.
Mormon Rocks – Enhance Erosion and Drainage Control Structures Mormon Rocks Fire Station main building and storage shed behind the main building (to the north) are positioned adjacent to a moderately steep, moderately burned slope. Increased runoff and sedimentation is expected to affect these structures that may cause moderate damage. The existing berm that surrounds the Fire Station at Mormon Rocks needs to be enlarged, the ditch capacity enhanced, and culvert cleaned out. Sandbags need to be placed around outbuilding for erosion control of nuisance sediment. These measures are intended to deflect runoff around these structures, and to prevent sediment from damaging these structures. The drainage ditch that directs slope runoff away from the facility is not expected to be adequately sized to handle post-fire runoff and sediment. Culvert that drains ditches and adjacent slopes is plugged. See Appendix E for treatment specs and site specific information.
Figure 11: Mormon Rocks Fire Station Engine Bay. Site is at risk of increased sediment delivery from steep, burned, sediment charged swales and drainages. Current erosion and drainage control measures are insufficient.
2. Non-National Forest Jurisdiction Facilities, Roads, Infrastructure, Private Property
Watershed specialists evaluated the issues of concern to determine values at risk (VARs), both on and off National Forest Lands,that may be affected by the change in watershed conditions as a result of the Blue Cut Fire. In addition to values at risk on National Forest lands, other values at risk as a result of the fire were identified on other jurisdictions beyond the National Forest, and recommendations for those values at risk made by watershed specialists are listed below (and Table 5):
Utilities, railroads, counties, CalTrans evaluate in detail the integrity of their infrastructure with consideration of predicted change in conditions identified in BAER Assessment Infrastructure and resources associated with the following entities were identified to be at risk from the effects of flooding, debris flows, rockfall, sedimentation and erosion. The BAER team was not able to conduct a detailed analysis of all the locations at risk of these post-fire effects. Additionally, not all of the information about some of the infrastructure was available to the team. It is strongly recommended that these entities closely consider debris flows, peak stream flows, erosion and sedimentation predictions made in the rapid BAER assessment and conduct a more detailed analysis of potential risks to their infrastructure: Southern California Edison (SCE), Los Angeles Department of Water and Power (LADWP), Union Pacific Railroad (UP), Burlington Northern Santa Fe Railroad (BNSF), San Bernadino, County – departments: Roads, Flood Control, Health, Los Angeles County- Roads department, Kinder Morgan petroleum lines, Southern California Gas, AT&T, CalTrans, State of California Department of Water Resources, California Regional Water Quality Control Board, Communities of Lytle Creek and West Cajon.
Railroads are particularly at risk from rockfall, debris flows, and peak stream flows, in the Cajon Canyon area, where high and moderate burn severity occurred.
Maintenance and/or improvement is recommended for stream crossings of roads and railroads in watersheds affected by high and moderate soil burn severity that show increased flows in the peak flow and sedimentation modeling as well as any roads located near, within, or downstream of the burn area. Examples of these roads include county roads, Highway 2 and Highway 138, and Interstate 15.
It is recommended that gas and petroleum pipeline entities evaluate the areas of high and moderate debris flow and erosion hazard rating, as well as the crossing of Cajon Wash. The crossing of Cajon Wash by the Kinder Morgan pipeline is in a segment of the stream channel where increased channel incision is predicted. The Kinder Morgan and Southern California Gas pipelines cross areas of very high erosion and debris flow hazard. Buried lines should be evaluated for risk from damage by erosion.
LADWP and SCE power infrastructure, including towers, poles and roads, was identified to be in areas of high and very high erosion, debris flow, sedimentation, and flooding hazards, and should be evaluated by these utilities for strategies to protect from damage.
Coordination of NRCS and other community entities to inform the affected private lands and public, and address private lands and structures at risk. Homes and other properties were observed to be at risk from flooding, sedimentation, erosion, and impact from debris flows. At extreme risk are properties adjacent to the burned area and steep slopes in the Lytle Creek area, properties adjacent to steep slopes in the West Cajon area as well as those located throughout the West Cajon vicinity, and on the west side of Cajon Wash in the Blue Cut area.
Installation of warning signs about flood and rock fall hazard on roads of their jurisdictions Risk of flash flooding and increased rockfall affecting the safety of main roads is a result of loss of vegetation from fire, particularly in watersheds that experienced high and moderate soil burn severity. Roads that should have warning signs about flash flood hazard are the Lytle Creek Road swale (near FS boundary) and stream crossings, and the Lone Pine and Swarthout Canyon Road at each point where the road crosses the main Lone Pine Canyon channel. Rock fall warning signs are also recommended were applicable.
Coordination of emergency warning system for flash floods The likelihood of flash flooding has increased as a result of the fire, and coordination of an emergency warning system is recommended to protect life and safety of residents and occupants of the Lytle Creek, West Cajon, and Lone Pine areas and any private residence located within the burn area on alluvial fans or in floodplains.
Removal of hazardous material from all runoff areas: especially stream channels, floodplains Debris remaining from burned structures in runoff areas presents risk of contamination of surface and groundwater, as hazardous materials are mobilized. It is recommended that coordination of the San Bernardino County Department of Health be conducted to address the threat of hazardous materials to be mobilized in runoff areas. Of particular concern are remnants of burned structures located in stream channels and floodplains.
Domestic, commercial, and municipal uses of water should anticipate a potential effect to water quality Increased sedimentation and ash may affect quality of water utilized by homes, business, and communities in the Lytle Creek watershed. The greatest effect will be in the Lytle Creek community, and minor effect is expected for the City of Fontana’s water intake in Lytle Creek. Runoff from burned infrastructure that may contain hazmat should also be considered for affects to water quality.
IV. REFERENCES
California Integrated Waste Management Board, 2007 “Pre-and Post-Removal Activity Results, Angora Fire, South Lake Tahoe, California” (document 003-09285-00)
Cannon, Susan H. et.al., DOI, 2011. Rainfall intensity-duration thresholds for postfire debris-flow emergency-response planning. Natural Hazards (2011). 59:209-236. DOI 10.1007/s11069-11- 9747-2.
DRI, 2013. Desert Research Institute, Western Regional Climate Center website - annual precipitation maps of southern California.
Foltz, R.B. et al. A Synthesis of Post-Fire Road Treatments for BAER Teams: Methods, Treatment Effectiveness, and Decision-making Tools for Rehabilitation.
Hubbert, K.R. et al. 2012. Effects of hydromulch on post-fire erosion and plant recovery in chaparral shrublands of southern California. International Journal of Wildland Fire, 21, 155-167. http://dx.doi.org/10.1071/WR10050
Kinoshita, A.M. et al. 2014. Evaluating Pre- and Post-Fire Peak Discharge Predictions Across Western U.S. Watersheds. Journal of the American Water Resources Association (JAWRA). 1-18. DOI: 10.1111/jawr.12226
National Oceanic and Atmospheric Administration (NOAA), 2014. Application listed in NOAA Atlas 2, Volume XI, Precipitation-Frequency Atlas of the United States, Volume XI---California. http://hdsc.nws.noaa.gov/hdsc/pfds/other/nca_pfds.html
Rowe, P.B., Countryman, C.M., and Storey, H.C. 1949. Probable Peak Discharges and Erosion Rates From Southern California Watersheds as Influenced by Fire. USDA Forest Service, California Forest and Range Experiment Station.
U.S. Army Corps of Engineers. 2000. Los Angeles District Method for Prediction of Debris Yield. 166 pp. http://www.spl.usace.army.mil/resreg/htdocs/DebrisMethod.pdf
USDA Forest Service, Old Grand Prix Fire BAER Assessment
U.S. Geological Survey. 2005. Southern California – Wildfires and Debris Flows. Fact Sheet 2005-3106. http://pubs.usgs.gov/fs/2005/3106/
USDA Forest Service, 2006. Burned Area Emergency Response Treatment Catalog. Watershed, Soils, Air Management 0625 1801—SDTDC.
USDI, USGS, 2013. USGS California StreamStats. http://water.usgs.gov/osw/streamstats/
Waananen and Crippen USGS, 1977, USGS Water-Resources Investigations 77-21: Magnitude and Frequency of Flooding in California.
Wohlgemuth, Peter M., Jan L. Beyers, and Peter R. Robichaud, 2011. The effectiveness of Aerial Hydromulch as an Erosion Control Treatment in Burned Chaparral Watersheds, Southern California. The Fourth Interagency Conference on Research in the Watersheds, 26-30 September 2011, Fairbanks, AK.
Consultations
Alex Tardy, National Weather Service, Warning Coordination Meteorologist, San Diego, CA
Jayme Laber, National Weather Service, Senior Service Hydrologist, Oxnard, CA
V. APPENDICES
A. MAPS OF POUR POINTS FOR EROSION AND DISCHARGE MODELING 1) Map of Pour Points for Erosion and Discharge Modeling: Overview 2) Map of Pour Points for Erosion and Discharge Modeling: Railroad Area 3) Map of Pour Points for Erosion and Discharge Modeling: Lytle Creek Area 4) Map of Pour Points for Erosion and Discharge Modeling: West Cajon Valley B. PRECIPITATION DATA USED FOR DESIGN STORM C. COMPARISON CHARTS OF PRE AND POST-FIRE DISCHARGE. D. MAPS OF POUR POINTS AND EROSION HAZARD RATINGS 1) Map of Pour Points and Erosion Hazard Ratings: Overview 2) Map of Pour Points and Erosion Hazard Ratings: Railroad Area 3) Map of Pour Points and Erosion Hazard Ratings: Lytle Creek Area 4) Map of Pour Points and Erosion Hazard Ratings: West Cajon Valley E. TREATMENT SPECS FOR MORMON ROCKS FIRE STATION
APPENDIX A: MAPS OF POUR POINTS FOR EROSION AND DISCHARGE MODELING MAP 1: OVERVIEW MAP 2: RAILROAD AREA
MAP 3: LYTLE CREEK AREA MAP 4: WEST CAJON VALLEY
APPENDIX B: PRECIPITATION DATA USED FOR DESIGN STORM
Blue Cut Fire 2016: Selection of storms for hydrologic modeling
APPENDIX C: COMPARISON CHARTS OF PRE AND POST-FIRE DISCHARGE
Charts have been divided into groupings based on basin size (large vs small) or by area of concern (example: Railroad pour points). Smaller sized basins
Comparison of Pre and Post-Fire Discharge (Part 1)
30 25 20 15 10 5 0 Discharge in cubic feet per second (cfs)
Modeled Subwatersheds
Pre-Fire Peak Flows Post-Fire Peak Flows
Moderately sized basins Comparison of Pre and Post-Fire Discharge (Part 2)
350 300 250 200 150 100 50 0 Hwy 138 Xing 1 PCT RR xing Pioneer & Hwy Sheep Can. / West Cajon Discharge in cubic feet per second (cfs) 138 Lytle Cr Rd Modeled Subwatersheds
Pre-Fire Peak Flows Post-Fire Peak Flows
Area of Special Interest
Comparison of Pre and Post-Fire Discharge (Part 3)
160
140
120
100
80
60
40
20
Discharge in cubic feet per second (cfs) 0 Railroad1 Railroad2 Railroad3 Railroad4 Railroad5 Railroad6 Railroad7 Modeled Subwatersheds
Pre-Fire Peak Flows Post-Fire Peak Flows
Larger sized basins
Comparison of Pre and Post-Fire Discharge (Part 4)
8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 Discharge in cubic feet per second (cfs)
Modeled Subwatersheds
Pre-Fire Peak Flows Post-Fire Peak Flows
APPENDIX D: MAPS OF POUR POINTS AND EROSION HAZARD RATINGS MAP 1: OVERVIEW
MAP 2: RAILROAD AREA
MAP 3: LYTLE CREEK AREA
MAP 4: WEST CAJON VALLEY
APPENDIX E: TREATMENT SPECS FOR MORMON ROCKS FIRE STATION
TREATMENT/ACTIVITY Mormon Rocks Fire Station PART E
NAME Structure Protection Spec-# NFPORS SPEC FISCAL YEAR(S) TREATMENT CATEGORY* Facility & Infrastructure (list each year): 2016, 2017 NFPORS SPEC WUI? Y / N TREATMENT TYPE * Protect Structures Y IMPACTED IMPACTED T&E COMMUNITIES AT RISK Yes SPECIES No * See NFPORS Restoration & Rehabilitation module - Edit Treatment screen for applicable entries.
WORK TO BE DONE (describe or attach exact specifications of work to be done):
A. General Description: Mormon Rocks Fire Station main building and storage shed behind the main building (to the north) are positioned adjacent to a moderately steep, moderately burned slope. Increased runoff and sedimentation is expected to affect these structures that may cause moderate damage.
Enhancement of an existing flood control berm is specified for the main building of the Mormon Rock Fire Station, and sandbags are specified to be placed on the upslope side of the storage shed located behind the main building. These measures are intended to deflect runoff around these structures, and to prevent sediment from damaging these structures.
B. Location/(Suitable) Sites: Mormon Rocks Fire Station
1. Berm: Enhancement of existing berm on the west side of the main fire station building
2. Sandbags: Placing sandbags upslope on the west side of the storage shed behind the main fire station building
C. Design/Construction Specifications: 1. Berm: Build up existing berm by 2 vertical feet and extend length by 30 feet around upslope side of building. Berm construction/enhancement should be done to achieve compaction of the soil material. Berm should be constructed in 2-inch deep lifts of material and slightly wetting lifts of material, then compacting with equipment to obtain optimal compaction.
2. Sandbags: Filled sandbags should be placed in an L-shape alignment on the back side (north and west sides) of the storage shed behind the main fire station building, sufficient to deflect runoff around the structure and prevent sediment from being deposited against structure. The sandbag barrier should be at least 2-3 sandbags high.
D. Purpose of Treatment Specifications (relate to damage/change caused by fire): To protect structures from flooding and sedimentation as a result of the Blue Cut Fire
E. Treatment consistent with Agency Land Management Plan (identify which plan): San Bernardino National Forest Plan
F. Treatment Effectiveness Monitoring Proposed: Inspect berm and sandbags after every significant rain event and areas behind structures affected by runoff upslope.
Blue Cut Fire BAER Specialist Report OHV Roads/ Trails & OHV Incursions Report Final Resource Specialty: Off Highway Vehicle Impacts & OHV Trails and Roads Fire Name: Blue Cut Month and Year: August, 2016 Author(s) Name and Home Unit Name: Travis Mason, [email protected], (909)382-2716 (San Bernardino National Forest, Front Country Ranger District) Updated by Todd Ellsworth, BAER team leader (Inyo National Forest) (760)937-2033
I. Potential Values at Risk (identified prior to the on-the-ground survey)
A. Resource Condition Assessment
(a) Resource Setting
There is current heavy OHV use in the Baldy Mesa and Summit/ Cleghorn OHV Areas. Within the Blue Cut Fire area there multiple use recreation impacts, including OHV incursions on off-system roads and trails which are likely to increase following the fire due to removal of vegetation.
Front Country Ranger District is highly visited due to the close proximity to Los Angeles and Inland Empire regions of Southern California. These populations are mostly day visitors looking for year round OHV riding opportunities close to home. Baldy Mesa and the Summit/ Cleghorn areas provide an easy and well developed trail system.
OHV trails and impacts traverses high desert terrain ranging across flood plains to arid, hot, steep ridgelines, rocky hillsides that susceptible to flash flooding and debris flows that historically have impacted Crowder Canyon, Swarthout Canyon, Lone Pine Canyon, Baldy Mesa and the Cajon Wash from high intensity thunderstorm activity during monsoon season and heavier winter events. Vegetation types include: Mixed Chaparral, Chamise chaparral, Big Cone Douglas-Fir Forest, Singleleaf Pinyon Woodland, Joshua Tree Woodland, Canyon Live Oak Woodland, Desert Transition Scrub Oak, Alluvial Scrub, Cottonwood Willow Sycamore Riparian Woodland. Storms of concern include high intensity thunderstorms and longer duration winter storms. “Pineapple express” a warm winter storm event have caused severe flooding in this area in the past. Winter storms can also include several inches of snow accumulation at higher elevations.
Post-fire OHV Impacts on Critical Natural and Cultural Values at Risk Threats to soil productivity, recovery of native vegetation, endangered species and cultural resources were identified by OHV specialists and a soil scientist. Expansion of OHV impacts is very likely to impact recovery of native vegetation
Appendix E: Survey Team Specialist Report Format – Page 1 and long term soil productivity. These impacts are associated with increased risk for establishment of noxious weeds in the burned area and chronic (long term) soil disturbance and sedimentation associated with increased post fire OHV trespass off system roads and trails. Increased chronic sedimentation is likely to impact occupied Arroyo Toad habitat (listed species), Desert Tortoise habitat in Baldy Mesa, Southwestern Willow Flycatcher in Cajon Wash and Sheep Creek, Least Bell’s Vicro in Cajon Wash, along with water quality downstream. Expansion of OHV impacts is very likely to occur on National Forest Lands adjacent to State Highway 138, Swarthout Cyn Rd, FSR 3N22, 3N29, 3N31 and 3N49 relevant to the Pacific Crest National Recreation Trail (PCT). Additionally, removal of vegetation has increased potential for illegal OHV incursion along 2N49, 2N88 (Lost Lake Day Use), 3N21 (Baldy Mesa Staging Area), 3N22 (Summit Staging Area), 3N24, 3N31, 3N31y, 3N49, 3N53, 3W24, 3W25, 3W26. Before the fire, vegetation played a major role in limiting OHV activity to system roads and trails. It is very likely that, following removal of vegetation by the fire, expansion of OHV use will expand beyond system roads and trails.
Impacts from off-highway vehicle use include mortality of tortoises on the surface and below ground, collapsing old desert tortoise burrows, damage or destruction of annual and perennial plant and soil crusts, soil erosion and compaction, and proliferation of weeds. Grazing and other disturbances have resulted in loss of native vegetation and type conversion of native vegetation. Another threat that has come to the forefront is the increased frequency of wildfire due to the invasion of habitats by non-native plant species. Changes in plant communities caused by non-native plants and recurrent fire can negatively affect the desert tortoise by altering habitat structure and species available as food plants.
There are two primary threats to the desert tortoise and its habitat directly tied to the Blue Cut Fire. First, there is increased potential of OHV use within the burn area. Even after the faster recovering species like chamise, scrub oak and buckwheat get re-established, the open nature of the vegetation and the slow recovery of the woody species such as manzanita and Ceanothus species (that would serve as a barrier to illegal OHV activity) allows for an increase in illegal off-road vehicle travel. The second threat is increased potential for type conversion of native vegetation.
(b) Findings of the On-The-Ground Survey
OHV System Roads and Trails After 5 days on the ground survey emergency conditions exist for specific sections of the Baldy Mesa OHV Area within or below burned areas where post fire erosion, flooding and/or debris flows are likely to occur especially on FSR 3N24, 3N21, 3N55 and the Baldy Mesa OHV Staging area. These emergency conditions are based on anticipated post wildfire impacts on roads, trails and forest visitors.
Threats to roads and trails and forest visitors, identified by an OHV, roads and soils scientists include:
Appendix E: Survey Team Specialist Report Format – Page 2 • Excessive erosion of the trail/ road tread caused by interception and diversion of runoff from steep burned hill-slopes • Scouring or deposition where road intersect with several larger drainages, numerous moderate drainages • Illegal OHV use on the Pacific Crest Trail • Illegal OHV use off of Forest System Roads • Increased potential for falling rocks and debris
B. Critical Values
Roads Values at Risk associated with Green Sicker/ OHV Roads in the Blue Cut Fire Burned Area and the PCT along forest service roads are: • Threat to life and safety of forest visitors using the OHV Roads System and BAER Implementation Team Members working on proposed treatments. Road/trail washout, headcuts, debris flows and falling rocks • Threat to property from damage or loss of segments of the trail system. Trail miles within the affected trail system are: o 3N21 Baldy Mesa 2.5 miles o 3N22 Elliot Ranch 1.5 miles. o 3N24 Desert Front 12.0 miles o 2N47 Cleghorn Ridge 7.2 of 15.2 miles o 3N47x Cleghorn Ridge 9 miles o Pacific Crest National Recreation Trail (PCT) With JT’s of FSR’s 3N22, 3N29, 3N31y, 3N31ya, 3N44, 3N47, 3N49, 3N89, & Swarthout Canyon Rd. o NOTE: Only road segments impacted by post fire scouring and/or depositional processes will be treated.
Trails Values at Risk associated with the trails in the Blue Cut Fire Burned Area are: • Threat to life and safety of forest visitors using the OHV trail system in the Baldy Mesa OHV Area and BAER Implementation Team Members working on proposed treatments. Trail washout, headcuts, debris flows and falling rocks. • Threat to property from damage or loss of segments of the trail system. Trail miles within the affected trail system are: o 3W24 5.9 miles o 3W25 Phelan Loop 2.6 miles o 3W26 Manzanita Wash Loop 3.5 miles o NOTE: Only trail segments impacted by post fire scouring and/or depositional processes will be treated.
OHV Staging Areas Values at Risk associated with the OHV Staging Areas in the Blue Cut Fire Burned Area are: • Threat to life and safety of forest visitors using the OHV Staging Areas and BAER Implementation Team Members working on proposed treatments. Road washout, headcuts, debris flows and falling rocks
Appendix E: Survey Team Specialist Report Format – Page 3 • Threat to property from damage or loss of segments of the trail system. Trail miles within the affected trail system are: o Baldy Mesa Staging Area o Summit Staging Area
Developed Recreation Values at Risk associated with the trails in the Blue Cut Fire Burned Area are: • Threat to life and safety of forest visitors using the Lost Lake, Applewhite Campground, Applewhite Picnic Area and BAER Implementation Team Members working on proposed treatments. Road/trail washout, headcuts, debris flows and falling rocks • Threat to property from damage or loss of segments of the trail system. Trail miles within the affected trail system are: o Lost Lake & FSR 2N88 o Applewhite Campground o Applewhite Picnic Area
(c) BAER Risk Assessment
Probability Magnitude of Consequences of Damage Major Moderate Minor or Loss RISK Very Likely Very High Very High Low Likely Very High High Low Possible High Intermediate Low Unlikely Intermediate Low Very Low
The probability that expansion of OHV impacts could impact recovery of native vegetation, long term soil productivity, T&E species and cultural resources is very likely in selected areas along FSR 3N22, 3N24, 3N29, 3N31, 3N31y, 3N49, 2N88 (Lost Lake Day Use), 3N21 (Baldy Mesa Staging Area), 3N22 (Summit Staging Area). Based on the degree and extent of post fire OHV trespass, impacts on soil productivity, water quality and Arroyo Toad habitat and Desert Tortoise habitat in Baldy Mesa are Very likely. The magnitude of consequences is moderate. Therefore, the BAER risk is very high. BAER treatments are recommended.
The probability that increased illegal OHV use on the Pacific Crest Trail could occur is very likely in selected areas where roads and the PCT have crossings, areas outside the OHV Staging areas, and along several FS roads within the burned areas. The magnitude of consequences is moderate. Therefore, the BAER risk is very high. BAER treatments proposed for recovery of native vegetation and long term soil productivity serve to reduce this risk.
C. Treatments
Appendix E: Survey Team Specialist Report Format – Page 4 Fences & Unauthorized Route Decommissioning The objective of these treatments is to reduce expansion of OHV impacts and associated impacts on critical BAER values at risk. These impacts include increased risk for establishment of noxious weeds in the burned area and chronic (long-term) soil disturbance and sedimentation. Increased chronic sedimentation is likely to impact occupied Arroyo Toad habitat (listed species) and water quality downstream. Additionally, post fire OHV disturbance is the primary concern for impacts on cultural resources within the burned area.
The BAER assessment team has proposed an OHV Resource Protection treatment to promote natural vegetative recovery by installing barriers, gates, fencing, and vegetation barriers to try to limit the amount of illegal cross-country vehicle use that is expected due to the lack of vegetation. The OHV Resource Protection treatment will help reduce the risk to desert tortoise from vehicles driving off road and will help speed the rate of habitat recovery by reducing the risk of spreading and establishing non-native plants. As mentioned above, there are sites within the Blue Cut Fire where smooth wire fencing has not been effective due to theft. However, the BAER team was able to identify some sites where use is lower or where wire can be combined with pipe and cable fence to achieve the desired objectives.
Smooth wire fence is proposed in areas where pipe and cable fence is deemed not necessary in order to reinforce the Forest Closure order in order to provide for public safety and protection of Forest Service investments. Smooth wire fences are the preferred method where they can be effective because they are less expensive in terms of materials and installation cost and it is faster to install.
Two miles of pipe and cable fence would be installed at strategic locations along Forest Road 3N24 to protect cultural resource sites from effects of off route driving. After fencing is in place, cultural sites would be seeded and planted to stabilize soils and to disguise sites from looting and vandalism. Container plants specifically grown for this location are available for planting immediately. Planted sites would be watered and maintained for 10 months to ensure vegetation success.
The SCMF crew that would be funded to construct fence will also plant, seed and install Fire Area Recovery signs. A Participating Agreement is currently in place to accommodate this work.
SCMF and USFS will contribute the following:
• SCMF will provide 2 miles of pipe fencing materials to install strategically located barriers along Forest roads 3N24. • 1,286 tall pots of 3 shrub species and 105 tall bullet pots that are available now and were grown from locally collected seed within the Blue Cut Fire. • 1,391 vexar cages for native plant herbivory prevention. • 50 pounds of local native seed. Watering tank and hose for watering crew over 10 months Even though this site is within the boundary of the Forest Closure order, enforcement will be extremely difficult and, without this treatment, these resources are at a very high risk during the planned closure period.
The sites identified in this treatment are on the edges of the Forest Closure area or at some internal sites that will have access via open County roads. These sites include 3N22, 2N88
Appendix E: Survey Team Specialist Report Format – Page 5 (Lost Lake Day Use), 3N21 (Baldy Mesa Staging Area), and 3N22 (Summit Staging Area) where vegetation burned and the areas are at very high risk of OHV incursions that threatened public safety and would slow natural recovery.
*NOTE: Locations along NFSR 3N22, 3N31, 3N31y, 2N88 (Lost Lake Day Use), 3N22 (Summit Staging Area)
In order to reinforce the Forest Closure Treatment, the Blue Cut BAER team is proposing decommissioning of unauthorized routes at two locations (3N24 across the forest boundary and 3N22 at Summit Staging Area) where numerous unauthorized routes connect the closure area with private land and public roads. With the types of recreational use and vegetation types present in the Blue Cut Fire Area, the SBNF has had success at decommissioning to protect resources after a fire when using “chunking” with excavators. Chunking, when combined with fencing/barriers, signs, and (most importantly) increasing patrol presence has been very effective. Any one of these methods without the others, has less success and requires more follow up treatments.
Chunking is described as using the bucket of an excavator or articulating blade on small trail dozer to de-compact unauthorized roads/trails by digging into the compacted area and creating divots (see below). These divots act as mini-catch basins (increasing infiltration), require minimal maintenance, and provide microsites for seed catchment and germination. In addition, container plants planted within the divots have high survival rates.
*NOTE: Locations along NFSR, 3N24, 3N22 (Summit Staging Area)
Monitor closure effectiveness This treatment includes a patrol person dedicated to the closure area, working weekends, holidays, and school vacation periods when use is highest, to enforce the closure maintain the structures, and augment closure structures as needed. The patrol would also help enhance presence during storms. This is an effective way to complete effectiveness monitoring of the closure and related treatments.
II. Discussion/Summary/Recommendations • Threats to soil productivity, recovery of native vegetation, impacts to T&E species and cultural resources were identified by OHV specialists, soil scientist, wildlife, botany and heritage resources specialists. Expansion of OHV impacts is very likely to impact recovery of native vegetation, long term soil productivity, and cultural resources and T&E species. • These impacts are associated with increased risk for establishment of noxious weeds in the burned area and chronic (long term) soil disturbance and sedimentation associated with increased post fire OHV trespass off system roads and trails • Increased chronic sedimentation and other OHV impacts are likely to impact occupied Arroyo Toad habitat (listed species), Desert Tortoise habitat in Baldy Mesa, Southwestern Willow Flycatcher in Cajon Wash and Sheep Creek, Least Bell’s Vicro in Cajon Wash, along with water quality downstream. • Recommend immediate treatment and repair as soon as practical along OHV Staging areas, several FS Roads. • Decommissioning of user created trails in the Baldy Mesa FSR 3N24 area, to reduce impact
Appendix E: Survey Team Specialist Report Format – Page 6 • Fencing of affected areas OHV Staging area junctions of FSR and the PCT • Patrols to monitor affected areas and educate forest visitors of fire recovery efforts. • Repair any unexpected heavy winter damage to ensure the protection and safety of forest visitors.
Appendix E: Survey Team Specialist Report Format – Page 7
Blue Cut BAER
San Bernardino National Forest
Soil Resource Assessment Report
4 September 2016
Kellen Takenaka - Soil Scientist/Geologist, Sierra National Forest Crystal Danheiser – Forester, Lassen National Forest
Page | 1 Soil Resource Setting The Blue Cut Fire started the morning of August 16, 2016 in the Cajon Pass along Old Cajon Blvd. north of Kenwood Avenue, west of Interstate 15. The fire quickly began spotting onto the San Bernardino National Forest and burned a total of 28,980 acres on both the Front Country Ranger District and the Santa Clara/Mojave Rivers Ranger District of the Angeles National Forest. The fire continued to burn for five days before it was declared contained by fire personnel on August 24th and burned a total of 36,240 acres. The Blue Cut Fire impacted the communities of Lytle Creek, Wrightwood, Summit Valley, Baldy Mesa, Phelan, and Oak Hills threatening the lives and property of residents residing within these communities. On national forest lands the fire burned over Joshua trees, chaparral, Pinyon pine, big cone Douglas-fir, and semi- desert riparian vegetation communities. Within the fire perimeter approximately 6,205 acres contained unburned/very low soil burn severity, 12,504 acres of low, 15,678 acres of moderate, and 1,852 acres of high, see Table 1 and Figure 1 in Appendix B.
Table 1: Blue Cut BAER soil burn severity (29/Sept/2015)
Soil Burn Severity Acres % Fire Area Unburned/Very Low 6,205 17% Low 12,505 35% Moderate 15,678 43% High 1,852 5% Total: 36,240
Soil Inventory The San Bernardino is made up of four principle mountain ranges of those, the San Gabriel was effected by the Blue Cut fire. The San Gabriel’s are separated from the San Bernardino range by the San Andreas Fault Zone creating what is known as the “main divide”. The surrounding faults have had tremendous influence on the landforms associated with the San Bernardino National Forest having many landslides, rock falls, and generally unstable areas. The east west trend of the mountain range also drastically influences the precipitation spectrum (2 to 5 inches on the desert side to as high as 40 inches on the mountain crest) which is often bested expressed in the diverse vegetation communities found within this range. This wide range in distribution of rainfall and topography play an intricate role in the development of the soils found within the San Bernardino Mountains. Of the soils analyzed in this report many consist of shallow and moderately deep, weakly consolidated rock material with already naturally erodible tendencies.
Soils surveys are used to analyze various soil characteristics e.g., soil type, texture, and rock content. The San Bernardino National Forest Area Survey (CA777) and the Soil Survey of San Bernardino County (CA671) were used for the soil’s assessment. Within the fire perimeter there are a total of 23 soil map units (SMUs), see Table 7 in Appendix A for a complete list of the soil map units and Figure 1 in Appendix B for a map display of these soils occurring within the fire perimeter. For further information regarding the soils found within the fire perimeter, both the CA777 and CA671 are available online, see Reference section of this report.
The top four dominant soils families within the burn area include Typic Xerothents, Soboba, Springdale, Olete, and Trigo see Table 2. A complete list is in Table 8 available in the Appendix A. Soil survey data was compared with data collected within the fire perimeter and site-specific observations to generate interpretations of fire effects upon known (visited) soils, and extrapolate interpretations for unvisited areas. This information provided basic soil characteristics for predicting post fire effects on soil productivity and erosion potential.
Blue Cut Fire BAER - Soil Resource Assessment Report
Table 2: Blue Cut Fire BAER top five dominant soil families
Soil Family Acres % Fire Area Typic Xerorthents 9,031 25% Soboba 5,846 16% Springdale 4,232 12% Olete 3,623 10% Trigo 3,348 9%
Soil Erosion Hazard Rating In order to assess the potential risk of a given soil to erode, the erosion hazard rating (EHR) system was developed within Region-5 of the United States Forest Service, Soil and Water Conservation Handbook (FSH 2505.22). The EHR system is designed to assess the relative risk of accelerated sheet and rill erosion processes only, and was developed primarily for land use activities such as agriculture or logging. The rating system is based on soil texture, depth, clay content, infiltration, rock fragments, effective surface cover, slope gradient, and climate (USDA Forest Service 1990). Risk ratings range from low to very high, with low ratings meaning low probability of surface erosion occurring. Moderate ratings mean that accelerated erosion is likely to occur in most years and water quality impacts may occur for the upper part of the moderate numerical range. High to very high EHR ratings mean that accelerated erosion is likely to occur in most years and that erosion control measures should be evaluated. For BAER purposes, fire induced changes to soil infiltration, ground cover, and runoff from adjacent areas can be factored in to determine changes in erosion hazard by soil burn severity classes, to produce a customized “post-fire EHR” map displaying erosion hazards on a relative basis.
To develop the EHR ratings for the soils on the Blue Cut Fire soil map units were evaluated using information relevant to texture, rock content, slope gradient, and characteristics relating to infiltration, permeability, and depth of the soil. EHR ratings were calculated for each soil with soil burn severity characteristics also factored in. Ratings thus represent a summary of soil physical characteristics, slope gradient, soil cover present, and level of hydrophobicity (water repellency) as observed in the field. Table 3 displays the EHR’s accessed within the fire perimeter. Appendix B, Figure 3 displays a map of this information.
Table 3: Blue Cut Fire BAER soil erosion hazard ratings (EHRs)
EHRs ACRES % of the Fire Area Low 10,882 30% Moderate 5,576 15% High 7,236 20% Very High 12,546 35%
Estimated Erosion Response Hydrologic soil groups are a standard soil-survey index of potential runoff response and subsequent erosion, this grouping is designated regardless of fire effects of soil characteristic used to classify each group. The associated value is used to determine the associated runoff curve number and is used to make direct estimates of runoff from rainfall (see Hydrology Report for more information). Hydrologic soil Group A have high infiltration rates even when thoroughly wetted, consisting chiefly of deep, well to excessively drained sands and/or gravel. Group B soils have moderate infiltration rates when thoroughly wetted, consisting chiefly of moderately deep to deep, moderately well to well drained soils, with moderately fine to moderately coarse textures. Group C soils have slow infiltration rates when thoroughly wetted, consisting chiefly of soils with a layer that impedes the downward movement of water or soils with moderately
Page | 3 fine to fine textures a slow infiltration rate. Group D soils have very slow infiltrations rates when thoroughly wetted, consisting chiefly of shallow soils over nearly impervious materials. Determinations are not made for miscellaneous land types such as riverwash or rock outcrop. Table 4 displays the total number of acres for each group. Appendix B, Figure 4 displays a map of each soil hydrologic group found within the fire perimeter.
Table 4: Blue Cut Fire BAER hydrologic soil groups
Soil Hydrologic Group Acres % of Fire Area A 7,897 22% B 22,993 63% C 3,996 11% D - - Riverwash (N/A) 1.009 3% Rock Outcrop (N/A) 4,400 1%
Post-Fire Condition Assessment The need for rapid assessment and mapping of soil burn severity (SBS) is essential to identifying areas of potential hazards caused by flooding or erosion to human and biological resources. Factors such as soil type, slope, and hydrologic
characteristics are important components in identifying risk and risk management.
It should be understood that soil burn severity is NOT vegetative burn severity or mortality; vegetative burn severity is but one component taken into consideration. Soil burn severity goes beyond aboveground vegetation impacts to belowground soil heating effects and associated impacts to soil. Hydrologic function, runoff, and erosion potential are influenced by pre-fire, fire, and post-fire environments. Soil burn severity includes careful consideration of factors such as, amount and condition of residual ground cover, viability of native seed banks, condition of residual fine roots, degree of fire-induced water-repellency, soil physical factors (texture, structural stability, porosity, restricted drainage), soil chemical factors (oxidation, altered nutrient status), and topography (slope gradient, length, and profile), and the length of time heat from the fire has been in contact with the soil (residence time). This differs from above-ground vegetation impacts as it is, more related to peak temperatures and fire behavior during the fire.
Understanding these factors that influence soil burn severity is an integral part in meeting the objectives of the BAER assessment. A high intensity fire (high flame lengths, rapid rate of spread, crown fire, etc.) in a stand-replacement event can result in a moderate (or even low) soil burn severity, if the residence time is short and soil characteristics are not altered significantly. Conversely, a slow-moving fire with long residence times and complete consumption of accumulated surface fuels can have negative consequences to soils and streams. Soil burn severity, used in this context, is a much better index of soil productivity, vegetative recovery, and overall watershed response in the post-fire environment.
Soil Burn Severity Soil burn severity indicators (Parsons et al 2010) were used to characterize the soil burn severity at field data points. These field points were then used to modify the BARC to better reflect the on-ground conditions and the final soil burn severity map was produced.
Blue Cut Fire BAER - Soil Resource Assessment Report
A total of 1,852 acres were identified as high soil burn severity (5% of the fire area) common characteristics of both a high and moderate soil burn severities are present, representative of the natural variability on the landscape. Very few areas observed within the fire perimeter were found displaying a “true” high soil burn severity. Ash color varied from gray to white with the ash layer ranging from less than 1” to 3” depending on landscape position and wind exposure. It was not uncommon to see deeper ash layers within low laying areas and flat topography. Soil organic matter consumption was often completely consumed destroying effective soil structure needed for slope stability, vegetative regeneration, and
moderation of runoff potential. The remaining ground cover Photo 1: Strong soil water repellency (hydrophobicity) was regularly completely consumed leaving only burned skeletons of the pre-existing vegetation. Soil water repellency (hydrophobicity) was variable down to three inches; included areas of weak (<10 seconds) too strong (>40 seconds) water repellency, see Photo 1 for a visual representation of strong hydrophobicity. Areas identified as high soil burn severity displayed common fire effects associated with dry fuels, deep litter layers, and longer residence times. These cumulative effects will like result in the higher likelihood of hillslope erosion and negative watershed response.
A total of 15,678 acres were identified with a moderate soil burn severity (43% of the area) see Photo 2. Ash color varied from black to white and ash thickness was commonly less than 1”. Minimal consumption of the soil organic matter had occurred and commonly only occurred to ¼ of an inch. Fine roots were frequently present but charred within this same depth range and soil structure varied from slightly too highly altered. Soil water repellency was patchy and included areas of weak (<10 second) too strongly (>40 seconds) hydrophobic soils. Ground cover within the moderate soil burn severity is similar to high soil burn severity with complete consumption of vegetative cover. What distinguish the two classes are often the overall watershed response and the presence of factors that influence the hazardous response. Infiltration of storm precipitation will vary depending on storm intensity and duration, possibly resembling a high watershed response similar to high SBS areas in the event of a severe storm.
Low soil burn severity represents 12,504 acres (35 % of the area), see Photo 3 for a visual representation. Little evidence of significant soil Photo 2: Moderate soil burn severity heating was observed within these areas. Very little vegetative consumption occurred leaving a charred look in patches. Ground cover was recognizable with little to no effective cover loss. Ash was generally white to black in areas of total consumption. Very little organic matter was consumed resulting in an unaltered soil texture. Water repellency was low to non-existent. It is often common for soils to exhibit natural water repellency however, the coarser texture of many of the soils found within the fire perimeter only slightly displayed this natural condition. The seed source within these areas would still be present in most of the topsoil and natural understory revegetation is expected to progress without delay. Areas of
Page | 5 unburned/very low constituted for the remaining 6,205 acres within the fire (17% of the area). These areas are likely to recovery quickly if left undisturbed with little acceleration of erosion and runoff potential outside of natural variability.
Estimated Erosion Response Quantitative erosion figures were estimated using the Erosion Risk Management Tool (ERMiT) batch model. ERMiT is a Water Erosion Prediction Project (WEPP-based application developed by USFS Rocky Mountain Research Station USFS, RMRS-GTR-188, 2007) specifically for use with post-fire erosion modeling. The model estimates only sheet and rill erosion, which occurs when rainfall exceeds infiltration rates, and surface runoff entrains surface soil particles. The model does not account for shallow landslides or gullying, stream-bank erosion, road effects, or fire-line erosion and gullying, which could present large additional sources of sediment entering the fluvial systems.
ERMiT models erosion potential based on single hillslopes, single-storm “runoff events,” and post-fire soil burn severity. Hillslopes include soil Photo 3: Low soil burn severity and topography inputs. Soil inputs include texture and matrix rock content, which was based upon soil map unit information and field verified in many areas of the fire as part of the assessment. Generalized hillslope gradients and profiles were developed in GIS by soil map unit, and soil burn severity class to account for fairly site specific differences in topography. Various storm runoff-event magnitudes may be chosen in ERMiT for erosion response estimates; 2-year, 5-year, and 10-year events were run for this analysis. ERMiT uses the PRISM module to generate climatic input parameters; a customized climate interpolated for San Bernardino, CA was generated for the fire area to account for the variations in precipitation across the fire perimeter.
Results of soil erosion modeling are reported by watershed name and only references watersheds within the fire perimeter both as burned and unburned (Table 5 and Table 6). The reported values are in total tons and tons per acre for the entire fire as a whole and each individual watershed within the fire. To help picture what a 1,000 tons of sediment might look like consider roughly 120 standard 10 cubic yard dump trucks filled up.
A 2-year storm event was modeled in ERMiT to determine if the estimated soil erosion for the fire area would affect soil productivity. The modeled 2-year event (50% probability) produced 192,805 tons of sediment equivalent to 4.7 tons per acre or 2,522 cubic yards per square mile (using a conversion factor of 1.35 tons per cubic yard). Increased hillslope erosion is expected to occur throughout the fire area. This increase in erosion is expect to be exasperated throughout the high and moderate soil burn severity areas, as soils within the fire perimeter are naturally erodible; which is reflected in the geomorphology of the area. The unburned, pre-fire conditions 2 year storm modeled a total of 2,090 tons of sediment equivalent to 0.06 tons per acre or 27 cubic yards per square mile. The stated accuracy of the model is +/- 50%.
Table 5: Blue Cut ERMiT batch unburned results
50% (2 Year) 20% (5 Year) 10% (10 Year) Area Tons/Acre Tons Tons/Acre Tons Tons/Acre Tons Blue Cut Fire 0.06 2,098 0.16 7,006 5.25 192,402 180902080502 0.02 9 0.10 41 1.76 70
Blue Cut Fire BAER - Soil Resource Assessment Report
50% (2 Year) 20% (5 Year) 10% (10 Year) Area Tons/Acre Tons Tons/Acre Tons Tons/Acre Tons Cajon Wash-Lytle Creek 0.10 3 0.21 6 8.10 245 Grass Valley Creek-West Fork Mojave 0.03 47 0.14 138 1.16 1,625 River Horse Canyon-Fremont Wash 0.02 53 0.12 242 2.32 5,935 Lower Cajon Wash 0.10 1,209 0.21 2,549 9.69 109,854 Manzanita Wash 0.02 10 0.09 111 1.32 821 North Fork Lytle Creek 0.06 85 0.13 169 4.55 6,461 Oro Grande Wash 0.02 22 0.10 171 1.13 1,801 Sheep Creek 0.04 19 0.14 74 3.86 1,893 Upper Cajon Wash 0.03 487 0.14 3,144 2.89 48,636
Table 6: Blue Cut Fire ERMiT batch burned results
50% (2 Year) 20% (5 Year) 10% (10 Year) Area Tons/Acre Tons Tons/Acre Tons Tons/Acre Tons Blue Cut Fire 4.7 192,805 11.9 537419. 19.2 862,442 180902080502 1.3 542 4.2 1,933 8.1 3,433 Cajon Wash-Lytle Creek 12.7 183 28.4 535 40.9 824 Grass Valley Creek-West Fork Mojave 1.8 1,503 5.4 4,256 9.2 7,503 River Horse Canyon-Fremont Wash 2.6 5,706 6.7 16,009 11.7 27,251 Lower Cajon Wash 8.3 93,784 20 252,477 30.6 379,260 Manzanita Wash 1.4 2,018 4.3 6,450 7.7 11,793 North Fork Lytle Creek 9.1 17,156 21.3 47,517 31.8 70,829 Oro Grande Wash 1.5 1,670 4.4 5,094 7.7 10,052 Sheep Creek 4.6 3,920 11.7 9,380 19.3 14,325 Upper Cajon Wash 3.5 67,834 9.3 197,157 16 339,616
Values at Risk – Threats to Life, Property, and Cultural & Natural Resources Based on the analysis done in this assessment the probability of damage or loss is considered to be likely, occurrence >50% to < 90%. The magnitude of consequence is considered moderate; injury or illness to humans, moderate property damage, and damage to critical natural or cultural resources resulting in considerable or long term effects. The combined probability of damage or loss and magnitude of consequence, results in a high risk for soil productivity. See the BAER Risk Assessment matrix within Appendix C.
Soil quality and hydrologic function throughout the fire was assessed by determining soil burn severity, soil erosion hazard, and evaluating the potential of on- and off-site effects to soil productivity, soil loss, and sedimentation. The combined effects of soil type, steep slopes, and lack of vegetative soil cover will create a watershed response with elevated erosion, sedimentation, and the potential for debris flows. Risks downstream of the fire will be elevated considering the close proximity of homes, roads, and utility infrastructure.
The degree of threat to the soil resource will be determined over the coming winter months and throughout the next 3- 5 years as soils and vegetation recovery stabilize. Potential impacts can be categorized into both on-site and off-site
Page | 7 effects. Unauthorized Off Highway Vehicle (OHV) use can increase soil loss and recovery times as well as damage or destroy cultural heritage and other natural resources such as threatened and endangered species. Natural re- establishment of cover can take many years to reach natural pre-burn cover conditions resulting in excess runoff and erosion until adequate cover is achieved. If extreme rainfall events occur within a five year period, high runoff and erosional events could occur resulting in a further loss of soil productivity, affects to water quality, or an increase in the potential for damage or loss of resource values downstream on and off Forest Service lands.
Natural hillslope erosion rates are rather low (< .5 tons/acre) when vegetated and covered with liter/duff; vegetation mortality and lack of cover in moderate and high SBS areas will certainly accelerate runoff and erosion processes in the post-fire environment, to what degree depends on the magnitude and intensity of coming storm events.
Emergency Determination and Treatments to Mitigate the Emergency Specific to soil productivity for a 2-Year (50% probability storm), fire wide average erosion rates of 4.7tons/acre were predicted. There is a threat of sedimentation and potential debris flows affecting downstream values at risk considering the close proximity this fire had to homes, roads, and utility infrastructure. Risks to roads exist throughout the fire area which are necessary to the transportation system (see Engineering Report) and represent valuable infrastructure investments; these are generally more effectively protected by road “hardening” treatments than land treatments. Regardless of the risk level or emergency determination, topography significantly limits the possibility for land treatments that would effectively reduce this risk (considered ‘untreatable’ with land treatments on slopes >60%), Thus the places where treatments would not effectively reduce the risks. For the life and safety Values At Risk (VARs), communicating and coordinating with Natural Resource Conservation Service (NRCS) is the only feasible option, to develop point-protection treatments in lieu of upslope treatments on private lands.
Blue Cut Fire BAER - Soil Resource Assessment Report
References
Tugel, A.J., Woodruff, G.A., 1978. Soil Survey of San Bernardino, California. Mojave River Area U.S. Department of Agriculture, Soil Conservation Service.
Cohn, B.R., Retelas, J.G., 1979. Soil Survey of San Bernardino National Forest Area, California, U.S. Department of Agriculture, Forest Service, and Soil Conservation Service in cooperation with The Regents of the University of California.
Parsons, A., Robichaud, P.R., Lewis, S.A., Napper, C., Clark, J.T, 2010. Field Guide for Mapping Post-Fire Soil Burn Severity. USDA Forest Service General Technical Report RMRS-GTR-243, 2010.
U.S. Department of Agriculture, Forest Service. 1995. Forest Service Handbook 2509.13 Burned-Area
Emergency Rehabilitation Handbook. Amendment No. 2509.13-95-7. pp 23.
U.S. Department of Agriculture, Forest Service. 2015. Remote Sensing Applications Center. Salt Lake City, UT. BARC map data is available at: http://www.fs.fed.us/eng/rsac/baer/barc.html.
U.S. Department of Agriculture, Natural Resources Conservation Service. National Soil Survey Handbook, title 430- VI. Available online at http://soils.usda.gov/technical/handbook/. Accessed 08/28/2016.
U.S. Department of Agriculture, Natural Resource Conservation Service (USDA-NRCS). 2015. Web Soil Survey Application. Available online at: http://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm.
Soil Survey data http://www.nrcs.usda.gov/wps/portal/nrcs/surveylist/soils/survey/state/?stateId=CA. Accessed 08/28/2016.
USDA Forest Service. Effective 2/5/2016. Ch. 50 Soil Erosion Hazard Rating. Soil and Water Conservation Handbook
Page | 9 Appendix A Table 7: Blue Cut Fire soil map units
Soil Map Soil Map Unit Name Acres % Fire Area Unit 102 Avawatz-Oak Glen Association, Gently Sloping* 170 0.47% 111 Bull Trail-Typic Xerorthents Association, Moderately Steep* 676 1.86% 121 Crafton-Sheephead-Rock Outcrop Association, Steep* 1 0.00% 126 Gullied Land-Haploxeralfs Association 790 2.18% 175 Wrightwood-Bull Trail Association, Sloping* 4 0.01% 175 Wrightwood-Bull Trail Association, Sloping* 505 1.39% AbD Soboba-Hanford Families Association, 2 To 15 Percent Slopes 5846 16.13% BeDE Wrightwood-Morical, Dry Families, Association 2 To 30 Percent Slopes 2180 6.02% BgEF Morical Family, Dry-Badland Association, 15 To 50 Percent Slopes 1953 5.39% ChFG Typic Xerorthents, Warm-Typic Haploxeralfs-Badland Complex, 30 To 100 Percent Slopes 7518 20.74% CmE Modesto-Osito Families Association, 15 To 30 Percent Slopes 68 0.19% CmF Osito-Modesto Families Association, 30 To 50 Percent Slopes 579 1.60% DnF Trigo Family-Lithic Xerorthents, Warm Complex, 30 To 50 Percent Slopes 485 1.34% DnG Trigo Family-Lithic Xerorthents, Warm Complex, 50 To 75 Percent Slopes 2863 7.90% EsD Riverwash-Soboba Families Association, 2 To 15 Percent Slopes 997 2.75% FLG Springdale Family-Lithic Xerorthents Association, Dry, 50 To 75 Percent Slopes 4049 11.17% FsD Wilshire-Oak Glen, Dry Families Association, 2 To 15 Percent Slopes 1568 4.33% JoG Springdale, Dry-Olete Families Complex, 50 To 75 Percent Slopes 183 0.50% MoFG Typic Xerorthents-Morical Family, Dry Association, 30 To 75 Percent Slopes 1514 4.18% PsD Avawatz-Oak Glen, Dry Families Association, 2 To 15 Percent Slopes 314 0.87% Rs Rock Outcrop, 30 To 100 Percent Slopes 345 0.95% Rw Riverwash 12 0.03% SgF Olete-Kilburn-Goulding Families Complex, 30 To 50 Percent Slopes 1 0.00% SgG Olete-Goulding Families-Rubble Land Association, 50 To 100 Percent Slopes 3622 10.00%
Blue Cut Fire BAER - Soil Resource Assessment Report
Table 8: Blue Cut Fire soil families
Soil Family Acres % Fire Area Typic Xerorthents 9,031 25% Soboba 5,846 16% Springdale 4,232 12% Olete 3,623 10% Trigo 3,348 9% Wrightwood 2,689 7% Morical 1,953 5% Wilshire 1,568 4% Riverwash 1,009 3% Gullied Land 790 2% Bull Trail 676 2% Osito 579 2% Avawatz 484 1% Rock Outcrop 345 1% Modesto 68 <1% Crafton 1 <1%
Page | 11
Appendix B
Figure 1: Blue Cut Fire soil burn severity map
Blue Cut Fire BAER - Soil Resource Assessment Report
Figure 2: Blue Cut Fire soil map units
Page | 13
Figure 3: Blue Cut Fire soil erosion hazard rating (EHR) map
Blue Cut Fire BAER - Soil Resource Assessment Report
Figure 4: Blue Cut Fire hydrologic soil group
Page | 15 Appendix C Table 9: BAER risk assessment
Magnitude of Consequences Probability of Damage or Major Moderate Minor Loss Risk Very Likely Very High High Low Likely Very High High Low Possible High Intermediate Low Unlikely Intermediate Low Very Low
Probability of Damage or Loss The following descriptions provide a framework to estimate the relative probability that damage or loss would occur within one to three years (depending on the resource):
• Very likely- nearly certain occurrence (>90%) • Likely- likely occurrence (>50% to < 90%) • Possible- possible occurrence (>10% to <50%) • Unlikely- unlikely occurrence (<10%)
Magnitude of Consequences • Major- Loss of life or injury to humans; substantial property damage; irreversible damage to critical natural or cultural resources. • Moderate- Injury or illness to humans; moderate property damage; damage to critical natural or cultural resources resulting in considerable or long term effects. • Minor- Property damage is limited in economic value and/or to few investments; damage to natural or cultural resources resulting in minimal, recoverable, or localized effects.
Blue Cut Fire BAER - Soil Resource Assessment Report Blue Cut Fire BAER Specialist Report Hiking Trails and OHV Incursions Report
Resource Specialty: Hiking Trails and Off Highway Vehicle Impacts Fire Name: Blue Cut Month and Year: August, 2016 Author(s) Name and Home Unit Name: Jeannette Granger (San Bernardino National Forest)
I. Potential Values at Risk (identified prior to the on-the-ground survey)
A. Critical Values
Trails Values at Risk associated with the trails in the Blue Cut Fire Burned Area are: • Threat to life and safety of forest visitors using the Pacific Crest and Mormon Rock Trails and BAER Implementation Team Members working on proposed treatments. • Threat to property from damage or loss of segments of the trail system. Trail miles within the affected trail system are: o Pacific Crest National Recreation Trail (PCT) 18.5m o Trail Segments: 2000.3, 2000.4, 2000.5, 2000.6 o Mormon Rocks Interpretive Trail #6W04 1.04m o TOTAL TRAIL MILES: 19.5 miles o NOTE: Only trail segments impacted by post fire scouring and/or depositional processes will be treated.
Post-fire OHV Impacts on Critical Natural and Cultural Values at Risk Off highway vehicle (OHV) use within and around the burned area is very high. Before the fire, vegetation played a major role in limiting OHV activity to system roads and trails. It is very likely that, following removal of vegetation by the fire, expansion of illegal OHV trespass will expand beyond system roads and trails.
B. Resource Condition Assessment
(a) Resource Setting
The PCT traverses high desert terrain ranging across flood plains to arid, hot, steep ridgelines, rocky hillsides and deep ravines susceptible to flash flooding and debris flows that historically have impacted Crowder Canyon, Swarthout Canyon, Lone Pine Canyon and the Cajon Wash from high intensity thunderstorm activity during monsoon season and heavier winter events. Vegetation includes typical sparsely wooded, heavy chaparral brush fields at all elevations with old growth Oak, Sycamore and Poison Oak drainages below the ridgelines. Small pockets of conifers and Big Cone Fir survive at the far northern edge of the fire.
Appendix E: Survey Team Specialist Report Format – Page 1
Storms of concern include high intensity thunderstorms and longer duration winter storms. “Pineapple express” rainfall events have historically caused severe flash flooding in this area. Winter storms can also include several inches of snow accumulation at higher elevations along the PCT corridor.
There is heavy OHV use in the general area and within the burn area. With the exception of the PCT and the Mormon Rocks Interpretive Trail there are no vehicle use prohibitions on authorized roads and OHV trails within the burn area. However, multiple use recreation impacts, especially OHV incursions, on off-system roads and trails, are likely to increase following the fire due to removal of vegetation.
(b) Findings of the On-The-Ground Survey
Pacific Crest Trail and Mormon Rocks Interpretive Trail Emergency conditions exist for specific sections of the Pacific Crest Trail within or below burned areas where post fire erosion, flooding and/or debris flows are likely to occur, especially at the Cajon Wash/Crowder Canyon confluence. These emergency conditions are based on anticipated post wildfire impacts on trails and trail users.
Threats to trails and trail users, identified by a trail specialist and soils scientists include: • Excessive erosion of the trail tread caused by interception and diversion of runoff from steep burned hill-slopes • Scouring or deposition where trails intersect with several larger drainages, numerous moderate drainages and crenulations • Illegal OHV use on the Pacific Crest Trail • Increased potential for falling rocks, debris and hazard tree damage
Post-fire OHV Impacts on Critical Natural and Cultural Values at Risk Threats to soil productivity and recovery of native vegetation were identified by rec. OHV specialists and a soil scientist. Expansion of OHV impacts is very likely to impact recovery of native vegetation and long term soil productivity. These impacts are associated with increased risk for establishment of noxious weeds in the burned area and chronic (long term) soil disturbance and sedimentation associated with increased post fire OHV trespass off system roads and trails. Increased chronic sedimentation is likely to impact occupied Arroyo Toad habitat (listed species) and water quality downstream. Expansion of OHV impacts from trespass is very likely to occur on NFS lands adjacent to the I-15, State Highway 138, Swarthout Canyon Rd, FSR’s 3N22, 3N44, 3N47, 3N49, 3N89, 3N29, 3N31Y and 3N31YA relevant to the PCT. Additionally, removal of vegetation has increased potential for illegal OHV incursion on the Pacific Crest Trail.
Appendix E: Survey Team Specialist Report Format – Page 2
(c) BAER Risk Assessment
Probability Magnitude of Consequences Tof Damage Major Moderate Minor hor Loss RISK eVery Likely Very High Very High Low Likely Very High High Low p Possible High Intermediate Low r oUnlikely Intermediate Low Very Low The probability of damage to the Pacific Crest Trail is very likely based on anticipated post fire scour and deposition processes (runoff, erosion, debris- flows). The magnitude of consequences is moderate. Therefore, the magnitude of consequences is very high. BAER treatments are recommended.
The probability that Pacific Crest Trail users could be impacted by falling rocks or trail failure is possible. The magnitude of consequences is major. Therefore, the BAER risk is high. BAER treatments are recommended.
The probability of damage to the Mormon Rocks Interpretive Trail is likely based on anticipated post fire scour and deposition processes (runoff, erosion, debris-flows). The magnitude of consequences is moderate. Therefore, the BAER risk is high. BAER treatments are recommended.
The probability that Mormon Rocks trail users could be impacted by falling rock, debris or trail failure is possible. The magnitude of consequences is major. Therefore, the BAER risk is high. BAER treatments are recommended.
The probability that expansion of OHV impacts could impact recovery of native vegetation and long term soil productivity is very likely in selected areas along FSRs 3N22, 3N44, 3N47, 3N49, 3N89, Swarthout Canyon Rd, 3N29, 3N31Y and 3N31YA. Based on the degree and extent of post fire OHV trespass, impacts on soil productivity, water quality and Arroyo Toad habitat are likely. The magnitude of consequences is moderate. Therefore, the BAER risk is high. BAER treatments are recommended.
The probability that increased illegal OHV use on the Pacific Crest Trail could occur is likely in selected areas. The magnitude of consequences is moderate. Therefore, the BAER risk is high. BAER treatments proposed for recovery of native vegetation and long term soil productivity serve to reduce this risk.
Appendix E: Survey Team Specialist Report Format – Page 3 Emergency Determination Based on the preceding risk assessments, emergency conditions for property (Pacific Crest Trail and Mormon Rocks Interpretive Trail) and critical natural resources (soil productivity, water quality, Arroyo Toad habitat) exist within the burned area. Increased risk for life and safety of Pacific Crest Trail and Mormon Rocks Trail users is also an emergency for which BAER treatments are proposed.
C. Treatments to Mitigate the Emergency
Trail Storm Proofing Prior to the first damaging rain events and within the first year following the fire, storm proofing is recommended to minimize erosion or removal of trail tread. Storm proofing treatments, implemented with hand-tools, would include out-sloping, de-berming, rolling dips, armored crossings at ephemeral drainages, and other suitable treatments outlined in the BAER Treatments Catalog to protect the trail from accelerated post fire flows and soil erosion.
Pre Winter projects would include 5-6 days of storm proofing treatments. Following winter storms and before spring opening, it is likely additional repairs would be needed requiring another 5-6 days of crew time. NOTE: This schedule will ensure the trail will be in good repair for 2017 Through Hikers.
Treatments are recommended for 18.5 miles of the Pacific Crest Trail (Sections 3-6) and 1.04 mile of The Mormon Rocks Trail. Treatments would only be applied where post fire scouring and/or depositional processes are likely to impact the trail.
Storm Inspection and Response The inspectors would repair and maintain storm proofing treatments by correcting expected problems prior to spring trail opening. Information gathered during these site visits may also be used to submit an interim funding request to the region. This treatment would be applied in the same zones of concern identified in the trail storm proofing section, above.
Warning Signs for the Pacific Crest Trail: Closure of the PCT is “to be determined”. There is strong public interest in the trail as a recreational opportunity. Some “hazard tree” risks exist for approximately one mile at the north edge of the fire. Signs to warn users of hazardous conditions will be installed as soon as practical if the trail remains open, or appropriate Forest Closure signage will be posted otherwise. Ongoing trail and watershed conditions will be evaluated, especially after the first winter following the fire. Early spring monitoring and repair of trail and watershed conditions will be scheduled to ensure the safety of heavy, annual “through hiker traffic”. Note: PCT Hikers using Hwy 138 or Lone Pine Canyon Rd as an alternate would risk extremely hazardous traffic conditions.
NOTES: -The proposal is subject to Heritage Review and Approval before Implementation -The probability of completing treatment in the first year prior to damaging storms or events is very likely (90%).
Appendix E: Survey Team Specialist Report Format – Page 4 -The probability of treatment success is likely to very likely (80%) although it is recognized that extreme precipitation events could impact the trail regardless of trail stabilization measures. -It may be necessary to prioritize the schedule of recommended treatments in two phases. Some preliminary treatments will be completed, (initial storm proofing i.e. rolling dips, berm removal etc.) prior to Monsoon or winter storms. -It is recommended we consider final treatment be delayed to coincide with Spring “Trail Opening” to ensure the safety and backpacking experience for 2017 PCT thru hikers.
I. Discussion/Summary/Recommendations • Recommend immediate minor treatment and repair as soon as practical along the PCT corridor, reserving ample funding to repair any unexpected heavy winter damage to ensure the protection and safety of spring through hikers.
• Implement the proposed fencing at Pacific Crest Trail junctions with FSR’s
*IN ADDITION: Fencing Treatments
Proposed Post and Cable Fencing and Walk Thrus - # Feet/Mile TBD Consult with OHV Advisor (Travis Mason) on final amount
Appendix E: Survey Team Specialist Report Format – Page 5
Caption: Caption: PCT Eastern aspect approximately 1mile Mormon Rocks Interpretive Trail: South of Gobblers knob. Some Big Cone Fir 5 switchbacks at the north end; 3 at the south populations may regenerate loop require storm proofing. 20 interp posts lost Treatment for structure protection of the Engine Bay directly downhill
Caption: Caption: Destroyed Bridge near the Culvert Trail Crowder Canyon Confluence Underpass in Section 5 near 3N49 High Risk of flash flood, debris flows, loss of tread
Appendix E: Survey Team Specialist Report Format – Page 6 NOXIOUS WEED DETECTION SURVEY and RAPID RESPONSE PLAN Fire Name: Blue Cut Fire Month/Year: August 2016 Author: Emma Williams, Jordan Zylstra Authors Duty Stations: Arapaho-Roosevelt National Forests and Pawnee National Grassland, San Bernardino National Forest
A. Background Forest Service policy mandates the Forest to minimize the establishment of non-native invasive species to prevent unacceptable degradation of the burned area. It is necessary to conduct noxious weed detection surveys to evaluate the potential for spread from both existing populations and from the activities associated with fire suppression. Therefore, noxious and invasive weed detection surveys are proposed for the first year following the fires to verify the suspected infestations and determine the fires’ potential impact on weed populations within the burned area. Giant reed (Arundo donax), wild oaks (Avena spp), cheat grass (Bromus tectorum), rip gut brome (Bromus diandrus), bull thistle (Cirsium vulgare), Uruguayan pampas grass (Cortaderia selloana), sweet fennel (Foeniculum vulgare), shortpod mustard (Hirschfeldia incana), broadleaved pepperweed (Lepidium latifolium), tree tobacco (Nicotiana glauca), Russian thistle (Salsola tragus), tumble mustard (Sisymbrium altissimum), Spanish broom (Spartium junceum), smilo grass (Stipa miliacea), and saltcedar (Tamarix ramosissima) are known to occur within the burn area and along access routes adjacent to the burn. During initial attack, an area occupied by yellow starthistle (Centaurea solstitialis) at Sycamore Station was briefly used as a staging area for suppression crews before being flagged off for avoidance. Many plant dispersal vectors such as Forest roads, high winds, and waterways occur within the fire area. Even though a weed washing station was utilized after two days of suppression activities, seed could have been transported into the burn on suppression vehicles and equipment that arrived on the fire before the washing station was established. Fire is known to enhance the establishment of all weed species present.
B. Management Concerns Noxious weed invasions interfere with habitat recovery and ecosystem health within burned areas and fire suppression sites. In particular, noxious weeds hinder the recovery of native habitat, especially in arid and riparian ecosystems, by aggressive colonization and reduction of water quality and quantity.
C. Objectives To determine if the fire and associated ground disturbing activities have promoted the establishment and spread of noxious weeds to the extent that eradication efforts are necessary. Early detection dramatically increases the likelihood of successful treatment. If weeds are detected, a supplemental request for BAER funds will be made for eradication.
D. Parameters Noxious weed presence, location, density, population size, and persistence.
E. Locations In and along roads, dozerlines, handlines, drop points, safety zones, riparian areas, and adjacent to known invasive plant populations.
Proposed Treatment Areas Dozerlines 31.5 Handlines 6.1 Riparian Corridors 69 Roads 77 Trail 29 212.6
F. Weed Detection Survey Design and Methodology Surveys will begin in 2017 during the flowering periods of weed species. Because of differences in flowering times for all potential species, two visits will be required during the growing season. Many of the species of concern are annual weeds which should be removed in the first year to reduce potential for establishment and persistence. Completion of surveys in roads, dozerlines, riparian areas, staging areas, safety zones, and known invasive plant populations will be the first priority. The second survey priorities will be along hand lines, and drop points. Surveys of the general habitats in the burned area will be the lowest priority. Weed species will be mapped, using the San Bernardino NF, “Invasive Weeds” list (Appendix C).
Early detection surveying will include documentation of new occurrences. Weeds documented in new areas will be pulled to root depth, placed in sealed plastic bags, and properly disposed of or, in approved areas (Appendix B), treated with the appropriate and approved herbicide.
Documentation of new infestations will include: • Mapping perimeter of new infestations • Filling out Weed Element Occurrence Form (Appendix A) • Treatment method required • Incorporating data into local GIS spatial database • Entering data into National Resource Information System (NRIS) database • Entering data into FACTS database • Evaluating success of treatment in subsequent inspections
G. Reporting If weed introduction and spread has occurred to the point that funding provided in the detection cost is not sufficient, an interim BAER report will be completed to request eradication funding. Reporting costs are included in figures below.
H. Weed Detection Surveys for One Year Weed detection surveys to determine whether ground disturbing activities related to the Blue Cut fire have resulted in the expansion of noxious weeds is requested for the first year. Estimated costs are based on the assumption that two visits would be necessary because of the differences in flowering times. If timing is such that all the target species are detectable and treatable in one visit, the actual costs would be lower.
I. Follow-up Actions Design and implement follow-up treatments as needed. Plan for integrated weed management and NEPA analysis using non-BAER funding.
APPENDIX A
USDA Forest Service Weed Occurrence Form Region_5_ Forest: Angeles District: ______
Species:______Date: ______ID confidence % ID Auth:_Hickman et al., 1993 Project Current land use: Surveyor Current/potential threats: Directions to site: Other biota: None Existing EO? Yes No # . Entire extent of pop mapped? Y N Photographer Site descrip: Repository Vouch spec # Repository Look-alike species: None Research needs (circle) Point Polygon Line GPS Unit: XT GeoEx3 Ipaq1 Ipaq2 Conserv/Mngt concerns Mag # Thales Other GPS Staff ID: # individuals, genets est, precise Unique ID #: #____pts/poly4EO Vigor? vfeeble feeble normal vigor exvirg N/A Method: Northing: Easting: (circle) Disease Predation Herbivory None Elevation (feet): Explain Quad name: Distribution/Density: prominent T-R-S: T R S common scattered patchy rare ¼ of ¼ of Gross (Total) area: est, precise Infested (Weed cover only) area : Slope Min. % Max % Cover: Sp. % Grd % Aspect (°): Substrate: Phenology method: est, count Soil text: sand, loam, silt, clay, other % seedlings % leaf % bud Moisture regime: mesic xeric hydric % flwr %immat frt % mature frt Soil moisture: dry moist saturated % dispersing seed % senescent inundated seasonal seepage other Treated before: Y N Horz dist. to H2O vert. Method of treatment: Light expos: full sun part shade full shade Fr suc: Exlt Gd Marg Pr Unkn Fair None Veg series: Germ suc: Exlt Gd Marg Pr Unkn Fair None Ass. tree/shrubs: Repro: Exlt Gd Marg Pr Unkn Fair None Canopy: % Shrub: % Dispersal: Exlt Gd Marg Pr Unkn Fair None Forb: % Assoc plants (include other non-natives): Estab: Exlt Gd Marg Pr Unkn Fair None Veg suc: Exlt Gd Marg Pr Unkn Fair None Fl suc: Exlt Gd Marg Pr Unkn Fair None
General observations Disturbance: Condition: Exlt Gd Marg Pr Unkn Fair None Quality: Exlt Gd Marg Pr Unkn Fair None Defense: Exlt Gd Marg Pr Unkn Fair None Rank: Exlt Gd Marg Pr Unkn Fair None Viability: Exlt Gd Marg Pr Unkn Fair None
APPENDIX B: Map of CalNev Mitigation Project Decision Area Where Herbicide Application Was Approved around Cajon Wash from HWY 138 south to Keenbrook Crossing
APPENDIX C: Invasive plants to watch for on the San Bernardino NF
TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA HIGH Potential to spread explosively
Arundo donax giant reed Washes, riparian High X X Brassica tournefortii African mustard washes, alkaline flats, Sonornan desert High X scrub Bromus madritensis ssp. rubens red brome shrublands, grasslands, desert scrub High X Bromus tectorum Cheat grass sagebrush, pinyon juniper woodlands, High X etc. Centaurea solstitialis yellow star thistle grasslands High X Centaurea stoebe ssp. micranthos spotted knapweed riparian, grassland, meadows, forest High syn. Centaurea maculosa X Cortaderia selloana pampas grass grasslands, wetlands, etc. High X Cortaderia jubata Purple pampas grass Disturbed sites, many habitats, High X especially coastal Cytisus scoparius Scotch broom Disturbed sites, many habitats High X Delairea odorata German ivy coastal shrublands, riparian High X Eichhornia crassipes water hyacinth waterways High ♦ Egeria densa Brazilian waterweed Streams, ponds, sloughs, Lake Fulmor High record Foeniculum vulgare wild fennel grasslands, shrublands High X Hedera helix (A) English ivy coastal and mountain forests, riparian High Hedera helix ssp.canariensis Canary ivy Woodland, chaparral, disturbed areas High Hydrilla verticillata hydrilla, waterthyme Ditches, canals, ponds, reservoirs, lakes High ♦ X Lepidium latifolium Perennial pepper weed Moist, seasonally wet places High X X Myriophyllum aquaticum Parrotfeather wetlands High ♦ Myriophyllum spicatum Eurasian milfoil, Water Ditches, lakes, lake margins, Big Bear L High milfoil, American milfoil, record. spike watermilfoil TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA Rubus discolor Himalayan blackberry riparian, marshes, woodlands High Spartium junceum Spanish broom roadsides, canyons, widespread High X X Tamarix chinensis, T. gallica, T. tamarisk, salt cedar desert washes, riparian, springs. High X parvifolia, T. ramosissima X
MODERATE potential to impact native ecosystems
Acroptilon repens Russian knapwed Fields, roadsides Moderate X Ailanthus altissima tree of heaven riparian, grasslands, oak woodlands Moderate X X Ageratina adenophora eupatory coastal slopes and canyons, riparian Moderate Atriplex semibaccata Australian saltbush grasslands, shrublands, alkali wetlands Moderate X Asphodelus fistulosus asphodel Disturbed areas, fields, highways Moderate ♦ Avena barbata, A. fatua slender wild oat coastal slopes, coastal sage scrub, Moderate X disturbed Brassica nigra black mustard coastal grasslands, disturbed areas Moderate X Bromus diandrus ripgut brome many habitat types Moderate X Carduus nutans Musk thistle Roadsides, pastures, waste areas Moderate Carduus pycnocephalus Italian thistle widespread Moderate X Centaurea melitensis tocolote widespread Moderate X X Cirsium vulgare bull thistle riparian, marshes, meadows Moderate X X Conium maculatum poison hemlock riparian, oak woodlands Moderate Cynodon dactylon Bermuda grass Moderate Dipsacus fullonum, D. sativus Fuller’s teasel roadsides and other disturbed sites Moderate Elaeagnus angustifolia Russian olive interior riparian Moderate Eucalyptus globulus Tasmanian blue gum riparian, grasslands Moderate Festuca arundinacea tall fescue coastal scrub, grasslands Moderate Ficus carica edible fig riparian woodlands Moderate Hirschfeldia incana Short-pod mustard Roadsides, creek bottoms, disturbed Moderate X areas Holcus lanatus velvet grass coastal grasslands, wetlands Moderate Hordeum murinum barley Moist, generally disturbed sites Moderate Kochia scoparia Mex. fireweed, Summer Disturbed places, fields, roadsides, Big Moderate TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA cypress, common red sage Bear L record Syn. Bassia scoparia Linaria genistifolia ssp. dalmatica Dalmatian toad flax mountain meadows, forest floor Moderate X Lepidium chalepensis Lens-pod whitetop Pastures, riverbanks, disturbed areas Moderate ♦ X Lolium multiflorum, L. ryegrass meadows and other wetlands, persistent Moderate perennemultiflorum if sown post-fire Nicotiana glauca Tree tobacco Coastal scrub, washes, roadsides Moderate X Oxalis pes-caprae (A) Bermuda buttercup disturbed grasslands Moderate Pennisetum setaceum (A) fountain grass roadsides, grasslands, etc. Moderate Phalaris aquatica Harding grass coastal, mesic soils Moderate Potamogeton crispus Curly leaf pondweed ponds, lakes, streams Moderate Retama monosperma Bridal broom Disturbed areas, alluvial fans; < 200 Moderate ♦ m Syn. Genista monosperma Schedonorus phoenix Tall fescue Disturbed places. Moderate Syn. Festuca arundinacea, Schedonorus Arundinaceus, Lolium arudinaceum Sisymbrium irio London rocket roadsides, grasslands, etc. Moderate Vinca major periwinkle riparian, oak woodland Moderate X Vulpia myuros Rat tail fescue Common, open places, sandy soils Moderate LIMITED potential to impact native ecosystems
Bassia hyssopifolia Bassia alkaline habitats Limited Bromus hordeaceus Soft brome Open disturbed places Limited Descurainia sophia tansy mustard Mojave desert scrub Limited Erodium sp. Stork’s bill widespread Limited Hypochaeris glabra Smooth cat’s ear Disturbed areas Limited Medicago polymorpha California bur-clover many habitat types Limited Olea europaea olive riparian Limited Picris echioides bristly ox-tongue disturbed sites, known near Lake Limited TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA Silverwood Piptatherum miliaceum Smilo grass creeks and canyons Limited Plantago lanceolata English plantain Waste places, lawns, roadside Limited Polypogon monspeliensis Rabbits foot grass Moist ditches, streams, moist disturbed Limited areas Prunus cerasifera cherry plum oak woodland, riparian Limited Ricinus communis castor bean coastal and interior, widespread Limited Robinia pseudoacacia black locust riparian, canyons Limited Rumex crispus Curley dock Disturbed places Limited Tamarix aphylla Athel tree Washes, roadsides, RR ROWs Limited Salsola tragus Russian thistle many habitats Limited X Salsola paulsenii barbwire Russian thistle Mojave desert scrub, disturbed sites Limited Saponaria officinalis bouncing bet meadows, riparian Limited Schinus molle Peruvian pepper tree riparian, canyons Limited Schismus barbatus Mediterranean grass coastal and desert shrublands Limited Schismus arabicus Arabian schismus Dry open disturbed areas Limited Silybum marianum milk thistle pasturelands, disturbed grasslands Limited Verbascum thapsus woolly mullein widespread Limited
Not listed by Cal-IPC
Aegilops cylindrica Joined goatgrass Dry, disturbed sites X Acacia baileyana Bailey’s acacia Roadsides, disturbed areas Capsella bursa-pastoris Shepard’s purse Disturbed sites, gardens Chenopodium album Lamb’s quarters widespread Centaurea benedicta Blessed thistle Roadsides, disturbed areas X Convolvulus arvensis field bindweed disturbed areas X Dimorphotheca sinuata cape marigold sage scrub, alluvial fan scrub Elytrigia elongata Tall wheatgrass Roadsides, disturbed areas, slopes Elytrigia intermedia Intermediate wheatgrass Open areas, slopes Euphorbia lathyris gopher plant interior sage scrub TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA Lathyrus latifolius Sweet pea many habitat types Lactuca serriola Prickly lettuce disturbed areas Lepidium perfoliatum clasping pepperweed Roadsides, fields X Lunaria annua dollar plant riparian, forest, woodland Malva neglecta Common mallow disturbed sites, roadsides Malva parviflora Cheeseweed mallow disturbed sites, roadsides Medicago sativa alfalfa roadsides Melilotus albus, M.officinalis sweet-clover many habitat types, invading rapidly in Bear X Valley, and along road between Lone pine canyon and Rt. 138 Mentha spicata v. spicata spearmint streamside Nerium oleander oleander persists/naturalizes in riparian Pennisetum clandestinum Kikuyu grass disturbed sites, roadsides Poa bulbosa bulbous bluegrass conifer forest and grassy mountain areas Ranunculus testiculatus Curveseed butterwort Waste areas, overgrazed pastures, scrub, canyons, washes, creek banks Senecio vulgaris groundsel Gardens, farmlands, other disturbed sites Silene gallica Common catchfly disturbed sites, roadsides Solanum triflorum Cutleaf nightshade Dry scrub, juniper woodland Sonchus oleraceus Sow thistle disturbed sites, roadsides, field Sisymbrium altissimum Tumble mustard disturbed sites, roadsides X Tanacetum parthenium Feverfew Known & being treated in grass valley Taraxacum officinale dandelion Lawns, fields, problem in T. californicum habitat Tragopogon dubius Goat’s beard disturbed sites, roadsides, field Tribulus terrestris puncture vine dry disturbed areas X X Not Listed by Cal-IPC - Plants for which current information does not adequately describe nature of threat to wildlands, distribution, or invasiveness. Further information is requested from knowledgeable observers. ♦ = Cal-IPC Alert
** = noted as a problem invasive in at least one area of SBNF. TABLE 1. INVASIVE / NON-NATIVE PLANT SPECIES OF THE SBNF Cal IPC rating for CDFA OCCURRENCE potential impact on Noxious DOCUMENTED IN SPECIES NAME COMMON NAME HABITATS weed list BLUE CUT BURN native ecosystems AREA *** = noted as a problem invasive in T&E habitat, important to manage in sensitive habitats
CDFA= California Department of Food and Agriculture. Noxious weed = any species of plant that is, or is liable to be, troublesome, aggressive, intrusive, detrimental, or destructive to agriculture, silviculture, or important native species, and difficult to control or eradicate, which the director, by regulation, designates to be a noxious weed. In determining whether or not a species shall be designated a noxious weed for the purposes of protecting silviculture or important native plant species, the director shall not make that designation if the designation will be detrimental to agriculture.
BLUE CUT FIRE FISH and WILDLIFE BAER REPORT
Resource Specialty Fish and Wildlife Fire Name Blue Cut Fire
Month and Year August 2016
Prepared By Robin Eliason, Drew Farr, and Kim Boss (Wildlife Biologists on the San Bernardino National Forest – Mountaintop and Front Country Districts) /s/ Robin Eliason September 8, 2016
Page 1 I. INTRODUCTION Objectives This Resource Assessment has two primary purposes: • Assess the post-fire effects of the Blue Cut Fire on federally-listed wildlife species and their habitats. • Develop treatments for species at risk to prevent permanent impairment of ecosystem structure and function or loss of population viability.
In some instances, direct effects of the fire on wildlife are documented, but they do not necessarily meet the purpose of BAER and so a detailed analysis is not provided. This report also includes an assessment of post-fire watershed response effects to several additional locally- important wildlife species as well as wildlife water sources (spring developments and guzzlers).
Resource Setting/ Fire Summary The Blue Cut fire burned 36,240 acres, the majority of the fire within the lower and upper Cajon Wash watersheds on the San Bernardino National Forest (SBNF). The Blue Cut Fire started on August 16, 2016 at 10:36 AM in the Cajon Pass along Old Cajon Blvd. north of Kenwood Avenue west of Interstate 15. The fire quickly spotted across Cajon Creek and grew into a large wildland fire. During the course of the fire fight, railroad lines, local roads, highway 138 and Interstate 15 were closed along with a large evacuation area that included Lytle Creek, Wrightwood, Summit Valley, Baldy Mesa, Phelan and Oak Hills. The fire was declared contained on August 23rd at 6:00 am.
The fire burned in surrounding watersheds such as North Fork Lytle Creek along the southern perimeter and Manzanita Creek along the northern perimeter, and burned into the high desert regions to the north. The fire burned between 2400 feet elevation at Cajon Wash to 6955 feet elevation on Lytle Creek Ridge in the San Gabriel Mountains. The Cajon Wash and tributaries dominate the watershed setting of the fire, and the San Gabriel Mountain Range to the west have elevations reaching 10,000 feet at the head of North Fork Lytle Creek. The drainage headwaters are steep and confined, flowing into extended and anastomosed low gradient channels and washes (alluvial fans and plains) with wide valleys such as Cajon Canyon, Lone Pine Canyon and Lower Cajon Wash. Lytle Creek and Cajon Wash merge below the mountains and flow into the Santa Ana River near San Bernardino.
Most of the streams have seasonal flow, usually from large storm events or during wet winter rain seasons and typically turn dry during the summer. Cajon Wash and Lytle Creek have sections of perennial stream flow. Primary streams can flow for extended periods during wet winters further down reaches and reach the Santa Ana River to the Pacific Ocean, the northern streams beyond the Cajon watershed flow into the Mojave River system to sinks. Streams can flood during storms and flow at high rates during the winter. In 1938 and 1969 when significant storms occurred, Lytle Creek near the mouth of the canyon had peak flows estimated to be 26,000 and 35,900 cubic feet per second, respectively.
The majority of precipitation in the area occurs from October through April, with the bulk coming from December through March. Summers are warm and Occasional summer convective storms, or monsoon storms can produce sudden and heavy rainfall that can cause flooding.
Page 2 Snowfall occurs in elevations above 5000 feet in winter and high elevation snowpack can develop. Annual precipitation is greatest within the upper Lytle Creek watershed along the south facing front of the San Gabriel range. The upper reaches of the Cajon watershed tend to have lower annual precipitation due to rain shadowing as storms release the bulk of precipitation on the San Gabriel Range before reaching the upper Cajon watershed.
The San Gabriel range rises abruptly from coastal valleys in an east to west orientation, where moisture from Pacific frontal systems is directed from the south to southwest. Storms tend to build along the range causing an orographic lift effect that can lead to significant amounts of precipitation if storm dynamics are in place. Average annual precipitation in Upper Lytle watershed is near 40 inches, 20 inches in the lower Cajon Wash, and 15 inches in the northern area of the fire near Baldy Mesa and Manzanita Creek. Powerful winter storms that tap into deep sub-tropical moisture can create high, intense rainfall rates on mountain slopes and are the storms that can cause significant flooding and debris flows in the major drainages. Although not common, these storms tend to be warmer with high snow levels, and warm heavy rain on existing snowpack can cause even larger floods that have historically caused damage to roads and infrastructure along the major streams and alluvial fans.
Potential Wildlife Values at Risk (Identified Prior to on-the-Ground Surveys) Critical Values: Threatened and Endangered Species There are five federally-listed endangered species are known from within and downstream of the fire area: southwestern willow flycatcher, least Bell’s vireo, arroyo toad, San Bernardino kangaroo rat, and desert tortoise. Critical Habitat occurs for San Bernardino kangaroo rat and arroyo toad within and downstream of the fire area.
One other endangered species, California red-legged frog, has historic habitat within and downstream/downslope from the fire but are considered extirpated from this portion of the San Gabriel and San Bernardino Mountains. This species will not be further addressed in this document.
The areas within the Blue Cut fire that are known to support T/E species are displayed in Table 1.
Table 1. Areas of Concern for Threatened/Endangered Species within the Blue Cut Fire area Location Species ARTO SBKR SWWF LBVI Occupied Critical Occupied Critical Occupied Occupied Habitat Habitat Habitat Habitat Cajon Creek/Wash X X X X X X Sheep Creek X Lost Lake X X Lytle Creek X X Little Horsethief Canyon X Lone Pine Canyon X* Crowder Canyon X ARTO=Arroyo Toad; SBKR=San Bernardino Kangaroo Rat; SWWF=Southwestern Willow Flycatcher; LBVI=Least Bell’s Vireo * Has not had suitable riparian habitat since the early 1990s.
Page 3
Post-Fire Soil Survey Results The BAER soils scientists field-verified the Burn Area Reflectance Classification (BARC) map, which is used to estimate soil burn severity (SBS). Description of methods (both development of the BARC and field verification methods) to determine SBS are described in detail in the Blue Cut Fire Soils Report. Soil burn severity ratings includes careful consideration of factors such as, amount and condition of residual ground cover, viability of native seed banks, condition of residual fine roots, degree of fire-induced water-repellency, soil physical factors (texture, structural stability, porosity, restricted drainage), soil chemical factors (oxidation, altered nutrient status), and topography (slope gradient, length, and profile), and the length of time heat from the fire has been in contact with the soil (residence time). Hydrologic function, runoff, and erosion potential are influenced by pre-fire, fire, and post-fire environments. Final ratings for SBS of the Blue Cut Fire are listed in Table 2. The map packet included at the end of this report displays the soil burn severity within key areas in the Blue Cut Fire.
Table 2. Blue Cut BAER Soil Burn Severity (2/Sept/2016) Soil Burn Severity Acres % Fire Area Unburned/Very Low 6,205 17% Low 12,505 35% Moderate 15,678 43% High 1,852 5% Total 36,240
Predicted Post-Fire Watershed Response Blue Cut BAER team hydrologists and soil scientists evaluated and modeled the predicted post- fire watershed response. The Blue Cut BAER Hydrology Report summarized the predictions as shown in Table 3, Table 4, Figure 1, Figure 2, Figure 3, and Figure 4. The yellow highlighted rows correspond to sites with rare species that are discussed in this analysis.
The analysis for pre- and post- fire hydrologic response and probability of flows is based on the probability of a 2-year storm occurring in the fire area. The 2-year design storm has a 50% chance of occurring in any given year, and a 97% chance of occurring in the next five years. Conversely, there is a 3% chance that the 2 year storm event will not occur in the next 5 years (during the recovery period). A damaging storm expected to occur within the fire burned area is a short duration, high intensity storm, such as the 2 year recurrence interval, 30 minute duration storm with approximately 0.54 inches of precipitation.
It is important to note that any “Value At Risk” found to be at risk during the 2 year event will still be at risk during greater events. Several locations within the analyzed area have an inherent risk of flooding and debris flows in greater recurrence interval storms. Information for recurrence interval storms for both ~5 year and ~10 year peak flows and erosion rates are also included in the analysis.
Page 4 Table 3. Comparison of Pre and Post-Fire Discharge at Selected Sites (pour points) intended to provide general trends of flooding risk. Percent increase in discharge represents the percent above normal. All pour points exhibit increases in flows compared to pre-fire discharge. Source: Blue Cut BAER Hydrology Report Post-Fire Discharge Compared % Increase in Pre-Fire Discharge Post-Fire Discharge Pour Point to Pre-Fire Discharge Discharge* ~Q2 Q5-6 Q10-12 ~Q2 Q5-6 Q10-12 ~Q2 Q5-6 ~Q10-12 Q2 Cajon Junction (near McDonalds) 6 9 13 10 16 22 ~Q10 ~Q25 ~Q80 67% Cajon Wash 1 (Below fire area) 3,130 5,376 7,819 4,354 7,096 10,045 ~Q4 ~Q11 ~Q26 39% Cajon Wash 2 (above community) 9 16 22 18 27 37 ~Q8 ~Q25 ~Q80 100% Hwy 138 Xing 1 (above wildlife habitat)–Crowder 46 77 110 68 109 149 ~Q4 ~Q12 ~Q28 48% Canyon Hwy 2 (basin near HWY) 7 13 19 11 18 24 ~Q4 ~Q9 ~Q20 57% Lone Pine Canyon (hillside wash) 3 6 10 8 14 21 ~Q10 ~Q25 ~Q75 167% Lone Pine Canyon at LADWP Rd Xing 407 772 1270 625 1092 1729 ~Q4 ~Q10 ~Q25 54% Lost Lake 2 4 7 3 6 9 ~Q3 ~Q8 ~Q25 50% Lytle Creek above community 875 1754 2823 900 1795 2880 ~Q2 ~Q5 ~Q10 3% Lytle Resort 1 (swale) 1 2 3 2 3 4 ~Q5 ~Q12 ~Q40 100% Lytle Resort 2 (swale) 0 1 1 1 1 2 ~Q5 ~Q12 ~Q40 150% Manzanita Wash 10 57 143 12 68 171 ~Q3 ~Q6 ~Q12 20% Middle Fork Lytle Cr Bridge 981 1966 3163 1033 2050 3282 ~Q3 ~Q6 ~Q13 5% PCT at RR Culvert Xing 70 119 169 117 184 251 ~Q5 ~Q20 ~Q40 67% Pioneer & Hwy 138 Xing 126 214 304 201 317 435 ~Q4 ~Q13 ~Q30 60% Railroad1 19 36 59 43 72 111 ~Q8 ~Q20 ~Q50 126% Railroad2 13 25 41 34 55 84 ~Q10 ~Q24 ~Q80 162% Railroad3 6 11 18 15 24 37 ~Q10 ~Q25 ~Q80 150% Railroad4 38 68 98 109 167 218 ~Q13 ~Q90 >Q100 187% Railroad5 8 14 21 23 35 46 ~Q15 ~Q100 >Q100 188% Railroad6 3 6 8 9 14 18 ~Q25 ~Q100 >Q100 200% Railroad7 15 25 35 25 39 53 ~Q5 ~Q20 ~Q50 67% Sheep Creek and Lytle Cr Rd Xing 23 46 73 39 71 110 ~Q4 ~Q12 ~Q30 70% Sheep Creek Wildlife Habitat 9 17 29 16 27 43 ~Q5 ~Q12 ~Q26 78% West Cajon Valley wash 37 63 89 60 94 129 ~Q5 ~Q15 ~Q40 62% *All percentages are increases above normal.
Page 5 Table 4. Comparison of Pre and Post-Fire Erosion at Selected Sites (pour points) intended to provide general trends of post-fire erosion potential. Source: Blue Cut BAER Hydrology Report Erosion in Cubic Yards Per Year (RCS model) Erosion Hazard Pour Point Pre-Fire Post-Fire % Increase Rating Cajon Junction (near McDonalds) 185 3,859 1986% Very High Cajon Wash 1 (Below fire area) 108,749 1,050,385 866% -- Cajon Wash 2 (above community) 307 6,585 2045% Very High Hwy 138 Xing 1 (above wildlife habitat) – Crowder Canyon 2,323 36,212 1459% High Hwy 2 (basin near HWY) 138 1,364 888% Very High Lone Pine Canyon (hillside wash) 144 4,301 2887% Very High Lone Pine Canyon at LADWP Rd Xing 18,488 196,457 963% Very High* Lost Lake 129 2,080 1512% Low Lytle Creek above community 49,396 76,632 55% Very High* Lytle Resort 1 (swale) 53 745 1306% Very High Lytle Resort 2 (swale) 14 194 1286% Very High Manzanita Wash ------Moderate Middle Fork Lytle Cr Bridge 55,359 111,609 102% Very High* PCT at RR Culvert Xing 2,342 37,634 1507% Very High Pioneer & Hwy 138 Xing 4,206 60,758 1345% High Railroad1 850 20,720 2338% Very High Railroad2 584 17,437 2886% Very High Railroad3 258 7,686 2879% Very High Railroad4 1,333 29,072 2081% Very High Railroad5 281 6,119 2078% Very High Railroad6 72 1,569 2079% Very High Railroad7 486 8,181 1583% High Sheep Creek and Lytle Cr Rd Xing 1,282 18,590 1350% Very High Sheep Creek Wildlife Habitat 408 5,998 1370% Very High West Cajon Valley Wash 1,237 18,225 1373% Very High * Estimated for within the burned area only.
Page 6 Figure 1. Smaller sized basins Comparison of Pre and Post-Fire Discharge (Part 1)
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Figure 2. Moderately sized basins Comparison of Pre and Post-Fire Discharge (Part 2)
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Page 7 Figure 3. Area of Special Interest Comparison of Pre and Post-Fire Discharge (Part 3)
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Figure 4. Larger sized basins Comparison of Pre and Post-Fire Discharge (Part 4)
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Page 8 Threats to Water Quality and Beneficial Uses of Water The Blue Cut BAER Hydrology Report summarized the threats as follows. Peak flow increases from the fire will also be bulked by ash, debris and other floatable and transportable material within stream channel areas of the fire. Temporary episodes of water quality degradation and fine siltation is likely during the first year after the fire to Cajon Canyon Creek and major tributaries. Less severe and localized water quality impacts to North Fork Lytle Creek below burned tributaries upstream and adjacent to the Lytle Creek residential area and downstream could occur. Beyond the first year, post-fire water quality impacts will be lessened as the burned watersheds recover. Beneficial uses, including wildlife/TE species habitat in Cajon Creek Canyon and Lytle Creek could experience temporary impacts post-fire.
Erosion Threats All the modeled subwatersheds will experience increases in erosion with the greatest increases occurring in subwatersheds with the most burned acres and the steepest slopes. Subwatersheds with a large percentage of unburned acres or flatter terrain exhibit less increases; however, areas within these subwatersheds that are in close proximity to the burn may still have increased sediment beyond that which resulted in modeling. The Blue Cut BAER Hydrology Report summarizes the predicted changes in the Erosion Hazard Ratings (EHRs) for different areas in the fire, including in T/E habitat.
Debris Flows The Blue Cut Fire occurred in a landscape characterized by debris flow and landslide processes, as indicated by alluvial fan deposits below steep slopes with visible relic and active headscarps. Debris flows can occur in any rock type, but are most common in metamorphic and sedimentary rocks. Debris flows can be initiated on slopes of 20° (36%) and greater and deliver quantities ranging between 100 – 1,000,000 cubic yards of rock, sediment and large woody material, depending on rainfall amounts, slope, and amount of unconsolidated soil, rock and sediment material available. Debris flows most commonly occur in burned areas within the 2-year span of time after the fire, in areas of moderate and high soil burn severity. The Blue Cut BAER Hydrology Report describes debris flow likelihood for different areas in the fire.
II. THREATENED/ENDANGERED SPECIES EVALUATIONS
1. Arroyo Toad (Anaxyrus californicus) A. Resource Condition Assessment – Arroyo Toad a) Resource Setting – Arroyo Toad The arroyo toad was federally-listed as Endangered in 1994 (59 Federal Register 64859). Final Critical Habitat was designated on February 9, 2011 (76 FR 7245 7467). The arroyo toad recovery plan was issued in 1999. It is listed as a Species of Special Concern by the State of California.
The arroyo toad is endemic to the coastal plains, mountains, and desert slopes of central and southern California and northwestern Baja California from near sea level to about 8,000 feet. Within these areas, arroyo toads are found in both perennial and intermittent rivers and streams with shallow, sandy to gravelly pools adjacent to sand or fine gravel terraces. Arroyo toads have
Page 9 evolved in a system that is inherently dynamic, with marked seasonal and annual fluctuations in rainfall and flooding. Breeding habitat requirements are highly specialized. Specifically, arroyo toads require shallow slow-moving stream and riparian habitats that are naturally disturbed on a regular basis, primarily by flooding.
The breeding period occurs from late January or February to early July, although it can be extended in some years depending on weather conditions. Breeding in mountainous habitats may commence later (May–June) and last longer (to August) than in the coastal portion of the range. When water temperatures reach 57° F, adult males advertise with a soft, high whistled trill. Receptive females seek out calling males based on the size of the male and the sound of his call.
Although males may breed with several females in a season, females release their entire clutch of eggs in a single breeding effort and probably do not produce a second clutch during the season. Eggs are deposited and larvae develop in shallow pools with minimal current, little or no emergent vegetation, and sand or pea gravel substrate. Embryos usually hatch in 4–6 days; the larval period lasts approximately 65–85 days.
After metamorphosis from June to August, the juveniles remain on the bordering gravel bars until the pool no longer persists. Sexual maturity is reached in 1-2 years. Little is known about movements or other behavior in the non-breeding season.
Juvenile arroyo toads spend more time exposed on terraces during the daytime than do adults, and are thus vulnerable to diurnal predators. Once juveniles are of sufficient size to dig burrows and bury themselves in sand, they become nocturnal. All age classes of post-metamorphic individuals tend to be active on rainy nights with moderate temperatures (above 45° F). Adults excavate shallow burrows for shelter during the day when the surface is damp or for longer intervals in the dry season.
Larvae feed by inserting their heads into the substrate and ingesting loose organic material such as detritus, interstitial algae, bacteria, and diatoms. Juveniles and adults forage for insects, especially ants and small beetles, on sandy stream terraces or around the drip line of oak trees.
The species has been extirpated from approximately 75 percent of its former range in the United States. Although the arroyo toad occurs mostly along coastal drainages, it has also been recorded at several locations on the desert slopes of the Transverse Ranges. On the SBNF, arroyo toad populations exist on tributaries of the Mojave River including lower Deep Creek, Kinley Creek, West Fork of the Mojave River, Cajon Wash, and Little Horsethief Creek.
On NFS lands, arroyo toad populations are localized and face a variety of threats including loss/degradation of riparian habitats, predatory non-native species, invasive non-native plants, non-native species outcompeting natural prey species, OHV impacts, dispersed and developed recreation impacts, water extractions and diversions, mining, and livestock grazing.
Arroyo toads and Critical Habitat are known to occur in and downstream/downslope of the fire, as listed below and displayed in the map packet.
Page 10 • Cajon Wash (in and downstream of fire) – occupied and Critical Habitat • Little Horsethief Canyon (downstream of fire) – occupied and Critical Habitat
b) Fire Effects – Arroyo Toad (ARTO) No focused surveys for arroyo toad were conducted as part of the BAER assessment. Fire activity was highest during the daytime. During this time of year, toads would be burrowed in the sandy terraces during the daytime. Although fire was less active at night when toads are active above ground, it is possible that toads were killed by the fire. Young metamorphs not able to dig down very deep would have been at the greatest risk of direct loss. Toads burrowed under leaf litter would also have been at risk during the fire since their cover would have been flammable.
Table 4 and the map packet display the amount of breeding and Critical Habitat in the fire by burn severity. The majority of the arroyo toad habitat burned was mapped as unburned or low severity. Direct effects from the fire were probably very minimal or none.
Table 4. Arroyo Toad Habitat (in acres) by Soil Burn Severity Habitat Land Unburned/ Low Moderate High Grand Total Type Ownership Very Low Occupied NFS 58 61 33 10 162 Breeding Non-NFS 75 74 48 5 203 Habitat Upland NFS 94 194 142 3 433 Habitat Non-NFS 104 139 113 2 359 Critical NFS 115 157 113 16 401 Habitat Non-NFS 190 184 121 8 503
c) Post-Fire Watershed Response Effects – Arroyo Toad The BAER hydrologists modeled 2-year storm events for this analysis, using parameters that simulate summer thunderstorms. Table 3 and Table 4 display the expected increases in peak flows and sediment contribution within arroyo toad habitat. Site-specific discussions follow.
Cajon Creek/Wash: Cajon Wash is occupied and Critical Habitat for arroyo toads. Toad breeding areas in Cajon Wash seem to vary with habitat disturbance and annual fluctuations in precipitation and stream morphology. Most of the Cajon Wash habitat area did not burn or experienced a patchy low severity burn.
The Blue Cut BAER Hydrology Report modeled flows for a number of different sites in the Cajon Creek/Wash habitat (Table 3 and Table 4 – Cajon Junction, Cajon Wash 1, and the Railroad Sites). The models indicate that there would be between 48 – 200% increase (depending on specific location) in flow in the arroyo toad occupied and Critical Habitat in Cajon Wash during a 2-year storm event.
Overall, Cajon Wash riparian areas will experience increased flows (a two-year storm will act like a 4-year storm; a 5-year storm will act like an 11-year storm) and localized effects from increased sediment and debris delivery. Under a two-year storm, the post-fire watershed
Page 11 response is not expected to scour the riparian vegetation. Deposition of sediment will be localized where side drainages come in to Cajon Wash/Creek. Erosion Hazard Ratings (EHRs) for sites in/leading to Cajon Wash are Very High.
Little Horsethief Canyon: The lower part of Little Horsethief Canyon has had the densest population of arroyo toad on the SBNF in the past; however recent surveys are lacking. The upper portion of the mapped habitat (the part within the Blue Cut Fire) is not suitable for breeding but is considered suitable as upland habitat. The fire just barely reached the mapped upland habitat in Little Horsethief. Burn severity was low in that area. Expected post-fire watershed response is expected to be minimal in the arroyo toad habitat.
Post-Fire Watershed Response Effects in Arroyo Toad Habitat: The greatest impacts to aquatic ecosystems within the fire area and immediately downstream will be higher water flows and higher levels of sediment delivery to stream channels resulting in greater scouring and deposition. There is also a much higher likelihood of debris flows that could result in rocks, boulders, soil, and vegetation flowing into and through the habitat in a fast-moving slurry.
Water quality is often affected for a short duration during the first post-fire heavy storm events occur as introduced ash and fine sediment are carried into aquatic systems. This can increase turbidity, change the pH and temperatures, and affect stream substrates. In some cases, water quality can be affected enough to affect toad health, especially when water quality if affected during the breeding season.
The level of effects to arroyo toads would depend on the size of the storm event. Adult arroyo toads would not be expected to be negatively affected by small or moderate levels of increased flows and sediments. In less severe storms, individual toads would likely survive and not be displaced; habitat may be enhanced due to sediment deposition and vegetation removal. A larger storm event would have higher levels of effects. A large storm that results in debris flows carrying boulders, rocks, and large woody debris would be expected to have more severe effects to individual toads. If storm events result in high sediment loading or debris flows, egg masses, tadpoles, and toads could be washed downstream, crushed by rocks and boulders moving through the system, or buried under debris/sediment.
The severity of effects would also vary with timing. Flooding or debris flows occurring when toads are closely associated to the water during the breeding season would be more likely to result in eggs, tadpoles, and young toads being flushed downstream, suffocated by debris, or killed in churning flows. Events during other times of year when toads are farther upland would generally have fewer effects unless debris flows and sediment occurred over burrowing sites smothering/burying individuals.
Since arroyo toads favor wide alluvial terraces, the results of debris flows, sediment delivery, and scouring of some vegetation may result in improved habitat over time. Or it may simply re- organize the habitat on the landscape as a result of channels and terraces moving.
The greatest post-fire risk to arroyo toads is lack of cover and forage where vegetation burned. Lack of cover increases predation and collection by people. Additionally, lack of vegetation
Page 12 increases the off-road cross-county vehicle traffic that puts arroyo toads at more risk and results in continued/additional habitat degradation. Non-native plants may also become established (without treatment) within burned areas, further degrading the habitat. Off-highway vehicle (OHV) use also promotes spread of non-native plants that degrade habitat quality.
B. Emergency Determination – Arroyo Toad The risk assessment matrix in Table 5 (from Chapter 2520 - Watershed Protection and Management) was used to determine the probability of damage/loss for arroyo toad.
Table 5. Risk Assessment Matrix Probability of Magnitude of Consequences Damage or Loss Major Moderate Minor RISK Very Likely Very High Very High Low Likely Very High High Low Possible High Intermediate Low Unlikely Intermediate Low Very Low Probability of Damage or Loss The following descriptions provide a framework to estimate the relative probability that damage or loss would occur within one to three years (depending on the resource): Very likely=nearly certain occurrence (>90%) Likely=likely occurrence (>50% to < 90%) Possible=possible occurrence (>10% to <50%) Unlikely=unlikely occurrence (<10%)
Magnitude of Consequences Major=Loss of life or injury to humans; substantial property damage; irreversible damage to critical natural or cultural resources. Moderate=Injury or illness to humans; moderate property damage; damage to critical natural or cultural resources resulting in considerable or long term effects. Minor=Property damage is limited in economic value and/or to few investments; damage to natural or cultural resources resulting in minimal, recoverable or localized effects.
Based on the likelihood of habitat damage due to increased OHV access/disturbance, increased non-native invasive plants, and debris flows during breeding season, the risk determinations for arroyo toad are: • Cajon Wash (within the fire) – VERY HIGH (Very likely probability with Major consequences) • Little Horsethief Canyon: VERY LOW (Unlikely probability with Minor consequences)
The BAER assessment team has determined that an emergency condition exists for the critical natural value of the federally endangered arroyo toad.
C. Treatments to Mitigate the Emergency – Arroyo Toad One of the threats to arroyo toad following the fire is debris flows during the breeding season that could kill individual toads or egg masses. However, no treatments are feasible to stabilize slopes and effectively reduce that risk. Other post-fire threats are the potential for increased
Page 13 OHV use and non-native invasive plants within occupied, suitable, and Critical Habitat for arroyo toads.
The BAER assessment team has proposed Forest Closure Treatments that includes installation of barriers, gates, fencing, and vegetation barriers to limit the amount of illegal cross-country vehicle use that is expected due to the loss of vegetation. The Forest Closure Treatments will help reduce the risk of death/injury to arroyo toads from vehicles driving off road. It will also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non- native invasive plants.
In addition, the BAER assessment team has proposed a Weed Detection and Rapid Response treatment will reduce the risk of arroyo toad habitat degradation from non-native invasive plants.
2. San Bernardino Kangaroo Rat (Dipodomys merriami parvus) A. Resource Condition Assessment – San Bernardino Kangaroo Rat The San Bernardino kangaroo rat was listed as Endangered by USFWS in January 1998 (FR 63 (185): 51005 - 51017). Critical habitat designated April 23, 2002 (67 Federal Register 19812). No recovery plan has been written for this species.
San Bernardino kangaroo rat is one of 19 subspecies of Merriam's kangaroo rat (Dipodomys merriami). San Bernardino kangaroo rat is distinguished from the other southern California subspecies by its darker body fur, smaller size and occurrence of four toes on its hind feet. This subspecies is one of the most highly differentiated of Merriam's kangaroo rats, possibly because of its complete geographic isolation from the other subspecies.
San Bernardino kangaroo rats are found primarily on sandy loam substrates, characteristic of alluvial fans and floodplains, where they are able to dig shallow burrows. They are always associated with alluvial fans. San Bernardino kangaroo rats can be found in all phases of alluvial fan sage scrub, as well as coastal sage scrub and even chaparral habitats within the species historical range. Soil texture plays an important role in habitat preference. Like other kangaroo rats, the San Bernardino kangaroo rat avoids rocky soils. The SBKR reaches its highest densities in early and intermediate seral stages. Early successional habitat provides the relatively open vegetation structure preferred by this subspecies.
The breeding season of Merriam's kangaroo rat lasts from mid-winter until spring depending on environmental conditions. In years with heavy winter rains and abundant herbaceous annuals, breeding activities may increase. Gestation is 33 days, and litter size averages 2.4 young. Weaning occurs 24–33 days after birth. In favorable years, females are capable of breeding shortly after weaning. They may breed twice in one year if conditions allow. Herbaceous material or free water is believed to be necessary for successful reproduction. Adult survivorship in San Bernardino kangaroo rat is high, and there is no difference in survivorship between the sexes. Individuals live approximately 5 years in the wild and 7 years in captivity.
Like other kangaroo rats, San Bernardino kangaroo rat is primarily nocturnal. It exhibits crepuscular activity, emerging from burrows at dusk to forage and returning to the day burrow
Page 14 before dawn. Individuals reduce surface activity in areas with less vegetation cover and on nights with high levels of moonlight.
San Bernardino kangaroo rat diet primarily consists of seeds, herbaceous material and insects, when available. D. merriami collects seeds in cheek pouches and stores them in scattered surface caches in the vicinity of home burrows. Green vegetation and insects are also important seasonal food sources. Insects, when available, have been documented to constitute as much as 50 percent of a kangaroo rat's diet. San Bernardino kangaroo rats are known for their ability to live indefinitely without water on a diet consisting entirely of dry seeds.
In the winters of 2004 and 2005, there was substantial flooding in Lytle Creek, Cajon Wash, and Bautista Canyon. San Bernardino kangaroo rats are adapted to periodic flooding, but the habitat has been severely altered by flood control measures primarily downstream of the SBNF. In addition, a large amount of emergency flood control work is conducted during and immediately after storm events. It is not clear what effect these emergency measures have had on the populations on and off NFS lands. a) Resource Setting – San Bernardino Kangaroo Rat San Bernardino kangaroo rats and Critical Habitat are known to occur in and downstream/downslope of the fire, as listed below and displayed in the map packet. • Cajon Wash (in and downstream of fire) – occupied and Critical Habitat • Lytle Creek (downstream of fire) - occupied and Critical Habitat b) Fire Effects – San Bernardino kangaroo rat No focused surveys for San Bernardino kangaroo rat were conducted as part of the BAER assessment. Fire activity was highest during the daytime when they would have been in their burrows. Although fire was less active at night when kangaroo rats are active above ground, it is possible that some kangaroo rats were killed by the fire. Since fire severity in the suitable/occupied habitat was mostly unburned/very low/low, the loss of individuals was probably very low.
Table 6 and the map packet display the amount of occupied and Critical Habitat by burn severity. The vast majority of the San Bernardino kangaroo rat habitat burned was mapped as unburned or low severity. Direct effects from the fire were probably very minimal.
Table 6. San Bernardino Kangaroo Rat Habitat (in acres) By Soil Burn Severity Habitat Land Unburned/ Low Moderate High Grand Total Type Ownership Very Low Occupied NFS 18 28 7 0 53 Habitat Non-NFS 64 39 5 0 108 Critical NFS 18 28 7 0 53 Habitat Non-NFS 64 39 5 0 108 c) Post-Fire Watershed Response Effects – San Bernardino Kangaroo Rat The BAER hydrologists and soil scientists modeled 5-year storm events for this analysis, using parameters that simulate summer thunderstorms. Table 3 and Table 4 display the expected
Page 15 increases in peak flows and sediment contribution within San Bernardino kangaroo rat habitat. Site-specific discussions follow.
Cajon Wash: Cajon Wash is occupied and Critical Habitat for San Bernardino kangaroo rat. The population in Cajon Wash is known to extend south of the National Forest boundary. The occupied habitat is described as a pioneer alluvial fan sage scrub community with a sandy substrate. Much of the Cajon Wash habitat area did not burn; the rest was a patchy low burn. The post-fire watershed response discussion above for arroyo toad habitat in Cajon Wash applies to San Bernardino kangaroo rat habitat in Cajon Wash.
Lytle Creek: Lytle Creek is considered occupied and is mapped Critical Habitat for San Bernardino kangaroo rat. Lytle Creek is an alluvial stream course. The stream channel is constantly changing due to flooding events. The creek bed is comprised of primarily sand, gravel, and boulders. Suitable San Bernardino kangaroo rat habitat in the reach of Lytle Creek has been highly modified by flood control activities. Nevertheless, small areas of undisturbed San Bernardino kangaroo rat habitat are scattered along the margins of the creek throughout the reach. The suitable habitat in Lytle Creek is about 2.5 miles downstream from the fire and was not directly affected by fire.
The BAER hydrology and soil models for Lytle Creek (Table 3 and Table 4) indicate that there would be a 5% increase in flow at the Middle Fork Bridge above the San Bernardino kangaroo rat occupied and Critical Habitat in Lytle Creek during a 2-year storm event. The EHR for that area within the fire perimeter is Very High.
Overall, Lytle Creek is expected to experience localized effects where side drainages come in to Lytle Creek. During the first storms, water quality will affected as ash and sediment delivery will be higher than normal and could be substantial in areas. Due to the large portion of the watershed that is outside the fire area, those sediment deliveries will be carried downstream during flood events. Effects will be mitigated by the large amount of the watershed that is outside the fire area.
Post-Fire Watershed Response Effects in San Bernardino Kangaroo Rat: The post-fire watershed response effects for San Bernardino kangaroo rat would be similar to those described above for arroyo toads in Cajon Wash. This species is adapted to and has evolved with periodic flood events and debris flows. For kangaroo rats, increase sediment delivery will enhance habitat. It is unlikely that severe scouring of riparian habitat will occur in Lytle Creek and Cajon Wash under a typical 2-5 year storm event post-fire. Larger storms, obviously, could result in more effects to habitat. Flooding, depending on how fast and how severe, could result in losses of kangaroo rats if they are unable to escape rising waters.
B. Emergency Determination – San Bernardino Kangaroo Rat The risk assessment matrix in Table 5 was used to determine the probability of damage/loss for San Bernardino kangaroo rat. Based on the likelihood of habitat damage due to increased OHV access/disturbance, increased non-native invasive plants, and debris flows, the risk determinations for San Bernardino kangaroo rat are:
Page 16 • Cajon Wash (within and below the fire): VERY HIGH (Very Likely probability and Major magnitude of consequences) • Lytle Creek (below the fire): LOW (Unlikely probability and Moderate magnitude of consequences)
The BAER assessment team has determined that an emergency condition exists for the critical natural value of the federally endangered San Bernardino kangaroo rat.
C. Treatments to Mitigate the Emergency – San Bernardino Kangaroo Rat One of the threats to San Bernardino kangaroo rat following the fire is debris flows during the breeding season that could kill individuals. However, no treatments are feasible to stabilize slopes and effectively reduce that risk. Other post-fire threats are the potential for increased OHV use and non-native invasive plants within occupied, suitable, and Critical Habitat for San Bernardino kangaroo rat.
The BAER assessment team has proposed Forest Closure Treatments that includes installation of barriers, gates, fencing, and vegetation barriers to limit the amount of illegal cross-country vehicle use that is expected due to the loss of vegetation. The Forest Closure Treatments will help reduce the risk of death/injury to San Bernardino kangaroo rats from vehicles driving off road. It will also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non-native invasive plants.
In addition, the BAER assessment team has proposed a Weed Detection and Rapid Response treatment will reduce the risk of San Bernardino kangaroo rat habitat degradation from non- native invasive plants.
3. Southwestern Willow Flycatcher (Empidonax traillii extimus) A. Resource Condition Assessment – Southwestern Willow Flycatcher a) Resource Setting – Southwestern Willow Flycatcher The southwestern willow flycatcher is federally- and state-listed as endangered and has a federal Recovery Plan. Critical Habitat was designated in 2005 and revised in 2013. Currently in California, southwestern willow flycatchers exist only in small disjunct groups and have been extirpated from the lower Colorado River.
Riparian communities provide both nesting and foraging habitat for the southwestern willow flycatcher. They feed primarily on insects and occasionally on seeds and berries. An important habitat component is the dense growth of the lower branches within willow thickets or a dense shrub understory. The nest site plant community is typically even-aged, structurally homogeneous, dense, and near surface water or saturated soil. Other characteristics such as dominant plant species, size and shape of habitat patch, canopy structure, and vegetation height vary widely among sites.
Most returning flycatchers show site fidelity to breeding territories; however, a significant number move within and among sites. Therefore, if a site is surveyed in one year and determined to be unoccupied, that does not mean it will not be occupied in successive years.
Page 17 About 25 nesting territories have been identified in the San Bernardino Mountains. Due to varying survey efforts, it is not known what percentage nest consistently. This paragraph from the San Bernardino County Museum summarizes the current understanding of southwestern willow flycatcher population status in the San Bernardino Mountains:
There is an emerging pattern at the larger scale of overall southwestern willow flycatcher occurrences in the San Bernardino Mountains. Since southwestern willow flycatcher surveys by SBCM began in 1999, the percentage of surveyed sites that had territories gradually increased from 39% in 1999, to 68% in 2000, and to an overall high of 76% in 2001. The following three years saw a steady reduction in the percentage of surveyed sites with territories until in 2004 there were no surveyed sites with territories. The most recent three years have yielded a small but steady increase in the percentage of surveyed sites with territories from 3% in 2005, to 6% in 2006, and 36% in 2007. The reason(s) for these apparent trends are not clear, but there does appear to be a cyclic nature to the occurrence of southwestern willow flycatcher in the San Bernardino Mountains. Ultimate factors driving the cyclic occupancy pattern are unknown at this time, but surveys in subsequent years may help to resolve this question.
The primary cause for the decline of the southwestern willow flycatcher is widespread fragmentation and extensive loss of both structural components and habitat resulting from hydrological changes in low elevation cottonwood-willow riparian habitat across the species' range. Other factors contributing to habitat losses include urban development, road development and maintenance, livestock grazing, high intensity and frequent wildfire, and human recreational activities.
Additional threats include brood parasitism by brown-headed cowbirds, replacement of native riparian vegetation by invasive nonnative species, pesticide contamination, predation, water management, and probable loss of winter habitat due to tropical deforestation. Throughout southern California, another ongoing effect to this species is from encroachment into the riparian zones by recreationists using the area for off-road vehicle use, enjoying nature, cooling off in the water, mountain biking, dog walking, etc. This type of encroachment can be expected to disturb nesting birds, possibly causing displacement, nest abandonment, lowered breeding success, degraded habitat, and individual mortality.
The known nesting territories for southwestern willow flycatcher within/near the Blue Cut fire are: 1. Keenbrook (downstream and downslope of the fire) – in Cajon Wash 2. Cajon Creek 1 (within the fire) 3. Cajon Creek 2 (within the fire) 4. Cajon Creek 3 (within the fire) 5. Cajon Creek 4 (within the fire) 6. Lost Lake (within the fire) 7. Lone Pine (within the fire) 8. Lytle Creek (outside the fire) 9. Sheep Creek (within the fire)
Page 18 Migrant willow flycatchers have been observed in Crowder Canyon (within the fire), indicating the habitat is suitable for breeding there even though nesting has not been recorded. Additional areas of unmapped suitable habitat were likely within the fire.
b) Fire Effects – Southwestern Willow Flycatcher No focused surveys for willow flycatcher were conducted for this BAER effort. It is assumed that southwestern willow flycatchers could be breeding in wherever suitable habitat is present within or downstream from the Blue Cut Fire. Table 7 and the map packet display the amount of occupied by burn severity.
The Blue Cut Fire burned after the peak of breeding season when most or all of this year’s young would be expected to have fledged; impacts to this year’s breeding productivity is anticipated to be little or none. Losses of individuals due to the fire may have occurred where the flame front moved too fast for birds to escape.
Table 7. Southwestern Willow Flycatcher Habitat (in acres) by Soil Burn Severity Habitat Land Unburned/ Low Moderate High Grand Total Type Ownership Very Low Occupied NFS 13 20 30 12 76 Habitat Non-NFS 2 12 16 4 34 TOTALS 15 32 46 16 110
c) Post-Fire Watershed Response Effects – Southwestern Willow Flycatcher The BAER hydrologists and soil scientists modeled 5-year storm events for this analysis, using parameters that simulate summer thunderstorms. Table 3 and Table 4 display the expected increases in peak flows and sediment contribution within southwestern willow flycatcher habitat. Site-specific discussions follow.
Cajon Wash Territories (Cajon Creek 1-4 and Keenbrook): Cajon Wash is occupied habitat for southwestern willow flycatchers. The area contains white alder, with some California sycamore, ash, and arroyo willow. The riparian area includes seepage on the upper benches of the stream course contributing to a dense nettle, wild grape, and poison oak understory. Non-native arundo and tamarisk is also present at places in Cajon Wash.
While the SBNF has mapped five separate territories based on past protocol-level surveys, the habitat in Cajon Wash should be considered an almost dynamic stringer of suitable habitat with nesting occurring at a number of sites within the suitable habitat. Due to the dynamic nature of riparian vegetation, the number and location of nesting territories and suitable habitat varies in any given year. Much of the Cajon Wash habitat area did not burn; the rest was a patchy low burn.
The post-fire watershed response discussion above for arroyo toad habitat in Cajon Wash applies to southwestern willow flycatcher habitat in Cajon Wash.
Lost Lake: Lost Lake is a linear sag pond associated with the San Andreas Fault in Lone Pine Canyon. The lake is approximately 50 feet wide by 250 feet long at full capacity; however, at
Page 19 the time of the Blue Cut fire it was almost completely dry. A perennial creek feeds Lost Lake, which contains a 250 meter long stretch of willows and cattail habitat. Habitat at the site consisted of willows no more than 5 meters tall, less in some areas, and no more than five meters wide. The continuous stand was 80% arroyo willow which was approximately 7 meters in height and 15% sandbar willow which forms a dense canopy to 5 meters. The willow habitat was confined to the eastern and about half of the northern shoreline. The surrounding uplands are covered by dense montane chaparral.
Lost Lake is a developed recreation site with a parking area. It is open to day use only but the use is very concentrated. Water-related dispersed recreation use is high at Lost Lake. The amount of use is believed to be high enough at several locations that it could affect the selection of nest sites for southwestern willow flycatcher. Unauthorized vehicle use sometimes takes place and damages riparian habitat. The drying of Lost Lake in summer 2016 has resulted in substantially reduced recreation use.
When water is present, Lost Lake is commonly used as a source of water for helicopters carrying buckets and using suction devices during wild fires. Tamarisk also occurs around Lost Lake. About ¾ of an acre of the suitable habitat for nesting at Lost Lake burned and became unsuitable during the 2014 Lost Fire. The remaining nesting habitat at Lost Lake was became completely unsuitable during the Blue Cut Fire.
The Blue Cut BAER Hydrology Report summarized the predicted post-fire watershed response for Lost Lake in Table 3 and Table 4, and as follows. Lost Lake is located in flat terrain, with soils that have high infiltration rates, and a small catchment area. Based on site specific field observations, the RCS erosion modeling for this site over-estimates the increase in sediment delivery to Lost Lake. Erosion and sedimentation of the Lost Lake pour point modeled area will experience increases in sediment but not at the level RCS modeled. The EHR model rated this area as Low Erosion Hazard Rating, which is more applicable based on field observations. Because this site is a recreational area, there is potential for increased erosion due to trampling and soil disturbance (OHV and hikers) before vegetation can re-establish. The BAER hydrology models for Lost Lake indicate that there would be a 50% increase in flow and in the southwestern willow flycatcher habitat in Lost Lake during a 2-year storm event.
Overall, Lost Lake is expected to experience an increase in flows and sediment but it is not expected to result in changes to that habitat conditions at the site.
Lone Pine Canyon: There is a record of breeding southwestern willow flycatchers in Lone Pine Canyon from 1993. The Lone Pine nesting territory site has not supported riparian habitat since the early 1990s. This site is no longer considered suitable for this species.
Sheep Creek: Sheep Creek is known to have had two successful nesting pairs of southwestern willow flycatcher in 2007. The suitable habitat was about 0.75 miles long paralleling Forest Road 2N56. Most of the suitable Sheep Creek habitat burned in the 2009 Sheep Fire. The upper portion of the mapped territory did not reburn in the Blue Cut fire and there is still some suitable habitat there. The lower estimated ¾ of the territory did reburn and is no longer suitable for nesting.
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The BAER hydrology and soil models for the Sheep Creek territory (Table 3 and Table 4) indicate that there would be a 78% increase in the southwestern willow flycatcher habitat in Sheep Creek during a 2-year storm event. Expected post-fire erosion potential in Sheep Creek Wildlife Habitat pour point is an increase of 1370% and was rated as a Very High EHR. This site is located in a steeper, transport section of the stream channel and will most likely experience incision and down-cutting; however, most of the riparian area did not burn (including a large stretch of Sheep Creek above the willow flycatcher habitat) and will help minimize erosion potential and effects from increased flows. Scouring of the southwestern willow flycatcher habitat in Sheep Creek is not expected.
Lytle Creek: The occupied/suitable habitat in Lytle Creek is about 2 miles downstream from the fire and was not affected by the fire. While the known nesting willow flycatcher site is about two miles downstream of the fire perimeter, there is suitable nesting habitat in Lytle Creek between that territory and the fire perimeter as well as farther downstream of the nesting territory.
The post-fire watershed response discussion above for San Bernardino kangaroo rat habitat is Lytle Creek applies to southwestern willow flycatcher habitat in Lytle Creek.
Crowder Canyon: Migrant willow flycatchers of unknown subspecies have been detected in the Crowder Canyon riparian habitat, indicating suitability for southwestern willow flycatcher nesting. Nesting is not known from the site but surveys have been limited and nesting may occur in that drainage.
The Blue Cut BAER Hydrology Report modeled potential post-fire watershed response for the Crowder Canyon willow flycatcher site (Table 3 and Table 4) (“Hwy 138 Xing 1 above wildlife habitat” in the models). The model indicates that there would be a 48% increase in flow in the southwestern willow flycatcher habitat in Crowder Canyon during a 2-year storm event. This southwestern willow flycatcher territory will experience increases in sediment delivery (approximately 1500% increase and rated as High EHR). This section of the channel is wider, braided, and more of a depositional area. The stream channel may experience some post-fire effects that are related to increased flows and sediment delivery such as channel migration, filling in of pools, and erosion; however, riparian vegetation is expected to respond/re-establish quickly, which will help stabilize the area. Additionally, leading to the habitat in this area are three tributaries, one of which (modeled) has a large depositional area upstream of the Highway 138 crossing. This depositional area will help minimize post-fire hydrologic and sedimentation effects.
Summary of Post-Fire Effects to Southwestern Willow Flycatcher: The expected post-fire watershed response impact to aquatic and riparian ecosystems within the fire area will be higher water flows and higher levels of sediment delivery to stream channels resulting in greater scour and deposition in some locations. Low debris flows will likely not impact riparian vegetation, but intensive debris flows could completely uproot and destroy riparian vegetation within the flood channel.
Page 21 Scouring of riparian habitat in the known territories may occur post-fire depending on the degree of flooding and debris flows. Complete scouring of nesting habitat is not expected under a 2 or 5 year storm event. If scouring occurs, fragmentation of willow habitat may occur as well as loss of important vegetative structure and cover. While this habitat would recover in several years (or longer if scoured to bedrock), there could be a period during which suitable nesting habitat is not available in the affected drainages. Whether the birds would return to the same area after an absence of several years is unknown.
Since many of the prey species for southwestern willow flycatchers are insects that have aquatic life stages, changes in water quality or introduction of environmental toxins could reduce prey availability (and thus, lower reproductive success or lead to reduced health).
If riparian vegetation is removed as a result of debris flows or flooding, there is an increased risk of non-native plants spreading or becoming established in the area. The establishment of non- native plants would hinder the recovery of the native riparian vegetation and the recovery of suitable southwestern willow flycatcher habitat.
Another significant post-fire risk to southwestern willow flycatchers is lack of cover and forage where vegetation burned off. Lack of vegetation increases the off-road cross-county vehicle traffic that will slow the recovery of habitat for this species by killing plants and spreading non- native plants.
If southwestern willow flycatchers that normally nest within the fire area are not able to relocate for the duration of time it takes for habitat recovery, they may experience increased rates of mortality and decreased reproductive success. If displaced birds relocate to new habitats, it is not known how long it would take for them to return to their previous territories.
B. Emergency Determination – Southwestern Willow Flycatcher The risk assessment matrix in Table 5 was used to determine the probability of damage/loss for southwestern willow flycatcher. Based on the likelihood of habitat damage due to increased OHV access/disturbance, increased non-native invasive plants, and debris flows, the risk determinations for southwestern willow flycatcher are: • Keenbrook and Cajon Creek 1-4 (downslope and in the fire): VERY HIGH (Very Likely probability and Major magnitude of consequences) • Lost Lake (in the fire): HIGH (Likely probability and Major magnitude of consequences) • Lone Pine (in the fire): LOW (Unlikely probability and Moderate magnitude of consequences) • Lytle Creek (outside the fire): LOW (Unlikely probability and Moderate magnitude of consequences) • Crowder Canyon (in the fire): LOW (Unlikely probability and Moderate magnitude of consequences) • Sheep Creek (in the fire): LOW (Unlikely probability and Moderate magnitude of consequences)
Page 22 The BAER assessment team has determined that an emergency condition does exist for the critical natural value of the federally endangered southwestern willow flycatcher due to the increased access to habitat for OHVs.
C. Treatments to Mitigate the Emergency – Southwestern Willow Flycatcher No specific treatment is proposed to treat threats to southwestern willow flycatcher habitat from flooding and debris flows due to the infeasibility and ineffectiveness of treatments to stabilize the amount of watershed affected in the Blue Cut fire. This type of habitat is resilient and expected to recover in a few years. Treatments to effectively reduce the risk of debris flows and flooding are not feasible.
The BAER assessment team has proposed Forest Closure Treatments that includes installation of barriers, gates, fencing, and vegetation barriers to try to limit the amount of illegal cross-country vehicle use that is expected due to the lack of vegetation. The Forest Closure Treatments will help reduce the risk of death/injury to southwestern willow flycatcher from vehicles driving off road. It will also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non-native plants.
In addition, the BAER assessment team has proposed a Weed Detection and Rapid Response treatment will reduce the risk of San Bernardino kangaroo rat habitat degradation from non- native invasive plants.
4. Least Bell’s Vireo (Vireo bellii pusillus) A. Resource Condition Assessment – Least Bell’s Vireo a) Resource Setting – Least Bell’s Vireo The least Bell’s vireo was listed as endangered on May 2, 1986 (FR 51(85): 16474-16481). Critical habitat was designated on February 2, 1994 (FR 59(22): 4845-4867) but there are no critical habitat units on the SBNF. A draft recovery plan was distributed to the public in 1998 but was not finalized.
The least Bell’s vireo is a small, olive-gray, migratory songbird that nests and forages almost exclusively in riparian woodland habitats. All subspecies of Bell’s vireo (Vireo bellii), including the least Bell’s vireo, are almost exclusively insectivorous and highly territorial.
Least Bell’s vireos generally begin to establish breeding territories by mid-March to late March. Most breeding least Bell’s vireos depart their breeding grounds by the third week of September, and only very few are found wintering in the United States. In some areas, they will also use adjacent upland habitats for foraging.
Least Bell’s vireos are apparently more restricted in choice of nesting habitat than other subspecies of Bell’s vireo. Least Bell’s vireo nesting habitat typically consists of well-developed overstories, understories, and low densities of aquatic and herbaceous cover. The understory frequently contains dense subshrub or shrub thickets. These thickets are often dominated by of sandbar willow (Salix hindsiana), mulefat (Baccharis salicifolia), young individuals of other willow species such as arroyo willow (S. lasiolepis) or black willow (S. goodingii), and one or more herbaceous species. Significant overstory species include mature arroyo willows and black
Page 23 willows. Occasional cottonwoods (Populus sp.) and western sycamore (Platanus racemosa) occur in some least Bell’s vireo habitats. Coast live oak (Quercus agrifolia) may also make locally important contributions to the overstory.
As much as 90 percent of the original extent of riparian woodland in California has been eliminated, and most of the remaining 10 percent is in a degraded condition. It appears that least Bell’s vireos nesting in areas containing a high proportion of degraded habitat have lower productivity (e.g., hatching success) than those in areas of high quality riparian woodland. Additionally, widespread habitat losses have fragmented most remaining populations into small, disjunct, widely dispersed subpopulations. Habitat fragmentation negatively affects abundance and distribution of neotropical migratory songbirds, in part by increasing incidence of nest predation and parasitism.
Least Bell’s vireos are sensitive to many forms of human disturbance including noise, night lighting, and consistent human presence in an area. Noise (e.g., bulldozers, OHVs, and hiker travel) can cause vireos to abandon an area. Much of the least Bell’s vireo decline is attributable in part to the combined, perhaps synergistic, effects of the widespread destruction of riparian habitats and brood-parasitism by the brown-headed cowbird (Molothrus ater).
There are ## known nesting territories for least Bell’s vireo within/near the Blue Cut fire: • Cajon Creek 1 (within the fire) • Cajon Creek 2 (below the fire) • Cajon Creek 3 (within the fire) • Cajon Creek 4 (within the fire) • Lost Lake (within the fire) b) Fire Effects – Least Bell’s Vireo No focused surveys for least Bell’s vireo were conducted for this BAER effort. It is assumed that least Bell’s vireo could be breeding in wherever suitable habitat is present in or downstream from the Blue Cut Fire. Table 8 and the map packet display the amount of occupied by burn severity.
The Blue Cut Fire burned after the peak of breeding season when most or all of this year’s young would be expected to have fledged; impacts to this year’s breeding productivity is believed to be little or none. Losses of individuals due to the fire may have occurred where the flame front moved too fast for birds to escape.
Table 8. Least Bell’s Vireo Habitat (in acres) By Soil Burn Severity Habitat Land Unburned/ Low Moderate High Grand Total Type Ownership Very Low Occupied NFS 0 4 10 6 20 Habitat Non-NFS 0 1 3 1 5 TOTALS 0 5 15 7 25
Page 24 c) Post-Fire Watershed Response Effects – Least Bell’s Vireo Cajon Wash Territories (Cajon Creek 1-4): Cajon Wash is occupied habitat for least Bell’s vireo. While the SBNF has mapped four separate territories based on past protocol-level surveys, the habitat in Cajon Wash should be considered a dynamic stringer of suitable habitat with nesting occurring at a number of sites within the suitable habitat. Due to the dynamic nature of riparian vegetation, the number and location of nesting territories and suitable habitat varies in any given year. Much of the Cajon Wash habitat area did not burn; the rest was a patchy low burn.
The post-fire watershed response discussion above for arroyo toad habitat in Cajon Wash applies to least Bell’s vireo habitat in Cajon Wash.
Lost Lake: See the description for Lost Lake under southwestern willow flycatcher. About ¾ of an acre of the suitable habitat for nesting at Lost Lake burned and became unsuitable during the 2014 Lost Fire. The remaining nesting habitat at Lost Lake was became completely unsuitable during the Blue Cut Fire.
The post-fire watershed response discussion above for southwestern willow flycatcher habitat in Lost Lake applies to least Bell’s vireo habitat in Lost Lake.
B. Emergency Determination – Least Bell’s Vireo The risk assessment matrix in Table 5 was used to determine the probability of damage/loss for least Bell’s vireo.
Based on the likelihood of habitat damage due to increased OHV access/disturbance, increased non-native invasive plants, and debris flows, the risk determinations for least Bell’s vireo are: • Cajon Creek 1-4 (in and downstream of the fire) : VERY HIGH (Very Likely probability and Major magnitude of consequences) • Lost Lake (in the fire): HIGH (Likely probability and Major magnitude of consequences)
The BAER assessment team has determined that an emergency condition exist for the critical natural value of the federally endangered least Bell’s vireo.
C. Treatments to Mitigate the Emergency – Least Bell’s Vireo No specific treatment is proposed to treat threats to least Bell’s vireo habitat due to the infeasibility and ineffectiveness of treatments to stabilize the amount of watershed affected in the Blue Cut fire. This type of habitat is resilient and expected to recover. Treatments to effectively reduce the risk of debris flows and flooding are not feasible.
The greatest threat to least Bell’s vireo habitat is the additional loss/degradation of habitat and disturbance caused by off-highway driving due to the loss of vegetative and other barriers. The BAER assessment team has proposed Forest Closure Treatments that includes installation of barriers, gates, fencing, and vegetation barriers to try to limit the amount of illegal cross-country vehicle use that is expected due to the lack of vegetation. The Forest Closure Treatments will help reduce the risk of death/injury to least Bell’s vireo from vehicles driving off road. It will
Page 25 also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non-native plants.
In addition, the BAER assessment team has proposed a Weed Detection and Rapid Response treatment will reduce the risk of San Bernardino kangaroo rat habitat degradation from non- native invasive plants.
5. Desert Tortoise (Gopherus agassizii) A. Resource Condition Assessment – Desert Tortoise a) Resource Setting – Desert Tortoise The desert tortoise is federally-listed as threatened in 1990 (55 FR 12178) and listed as threatened under the California Endangered Species Act in 1989. The desert tortoise has a revised Recovery Plan. Critical habitat for the desert tortoise was designated on February 8, 1994 (59 FR 5820). No designated or proposed Critical Habitat for desert tortoise occurs on or near the SBNF.
The desert tortoise is a large, herbivorous reptile and the only naturally occurring tortoise in the Mojave Desert. Large individuals can reach 15 inches in length. Their shells are generally highly domed and unhinged; some variation in the shape of the shell occurs among individuals, particularly across its range.
Desert tortoises occur in the California desert from below sea level to an elevation of 7,300 feet, but the most typical habitat is below 5,500 feet. The desert tortoise is most commonly found within the desert scrub vegetation type, primarily in creosote bush scrub vegetation, but also in succulent scrub, cheesebush scrub, blackbush scrub, hopsage scrub, shadscale scrub, microphyll woodland, and Mojave saltbush-allscale scrub.
Within these vegetation types, desert tortoises potentially can survive and reproduce where their basic habitat requirements are met. Throughout most of the Mojave Region, tortoises occur most commonly on gently sloping terrain with soils ranging from sand to sandy-gravel and with scattered shrubs, and where there is abundant inter-shrub space for growth of herbaceous plants. Throughout their range, however, tortoises can be found in steeper, rockier areas. This species normally excavates a burrow under bushes, overhanging soil or rock formations, or digs into soil in the open.
Desert tortoises in the Mojave Desert are primarily active between May and June, with a secondary activity period from September through October. During inactive periods, tortoises hibernate, aestivate, or rest in subterranean burrows or caliche caves, spending as much as 98 percent of their time underground. During active periods, they usually spend nights and the hotter portion of the day in their burrow. Tortoises construct and maintain a series of single opening burrows, which may average from 7 to 12 burrows at a given time.
Common ravens, gila monsters (Heloderma suspectum), kit foxes (Vulpes macrotis), badgers (Taxidea taxus), roadrunners (Geococcyx californianus), and coyotes are all natural predators of the desert tortoise. These predators typically prey upon 2- to 3-inch long juveniles, which have a thin, delicate shell. Desert tortoise decline is attributed to destruction and degradation of habitat
Page 26 by urbanization, agriculture, mining, livestock grazing, and off-road vehicle activity; predation; and disease. Upper respiratory tract disease, which prompted the emergency listing of the desert tortoise, has continued to spread. Although some roads have been fenced to prevent entry by desert tortoises, individuals continue to be killed by vehicular traffic.
The Recovery Plan for desert tortoise listed a number of threats for this species, including those that result in mortality and permanent habitat loss across large areas, such as urbanization, and those that fragment and degrade habitats, such as proliferation of roads and highways, off- highway vehicle activity, poor grazing management, and habitat invasion by nonnative invasive species. Indirect impacts to desert tortoise populations and habitat are also known to occur in areas that interface with intense human activity.
Another threat is the increased frequency of wildfire due to the changes in desert plant communities from invasions by non-native plant species. These changes affect fire frequency and can negatively affect the desert tortoise by altering habitat structure and species available as food plants. Off-highway vehicle activity, roads, livestock grazing, agricultural uses, and other activities contribute to the spread of non-native species.
Landfills potentially affect desert tortoises and their habitat through fragmentation/loss of habitat, introduction of toxins/trash, increased road kill of tortoises on access roads, and increased predator populations. Large-scale renewable energy projects have been approved and proposed within desert tortoise habitat, threatening more effects to habitat and tortoises. Additional threats include disease and predation, illegal collections, and climate change.
a) Fire Effects – Desert Tortoise The northern edge of the fire area supports suitable habitat for desert tortoise. All of the area below about ~4500’ in elevation with desert soil and vegetation types (generally north of Highway 138) is considered occupied habitat if suitable soils and habitat components are present.
No focused surveys for desert tortoise were conducted as part of the BAER assessment. The northern edge of the fire area supports suitable habitat for desert tortoise. All of the area below about ~4500’ in elevation with desert soil and vegetation types is considered occupied habitat if suitable soils and habitat components are present. No tortoise sightings were reported to or by the Blue Cut Fire Resource Advisors. In areas where the fire overlapped suitable habitat for tortoise, the fire behavior was very low and spotty due to the sparseness of vegetation to carry fire. That area was mapped as low soil burn severity (see the map packet). Individual tortoises could have been affected by the fire.
Table 4. Desert Tortoise Habitat (in acres) By Soil Burn Severity Habitat Land Unburned/ Low Moderate High Grand Total Type Ownership Very Low Occupied NFS 2,235 4,182 3,062 4 9,484 Habitat Non-NFS 1,238 2,094 446 0 3,777 TOTALS 3,472 6,276 3,508 5 13,261
Page 27 b) Post-Fire Watershed Effects– Desert Tortoise A post-fire risk to desert tortoises is lack of cover and forage plants where vegetation burned off. Lack of cover increases predation and collection by people. Additionally, lack of vegetation increases the off-road cross-county vehicle traffic that puts tortoises at more risk of collection or injury/death from being run over or crushed in burrows. Changes in plant communities caused by non-native plants and recurrent fire can negatively affect the desert tortoise by altering habitat structure and species available as food plants.
There are two primary threats to the desert tortoise and its habitat directly tied to the Blue Cut Fire. First, there is increased potential of OHV use within the burn area. Even after the faster recovering species like chamise, scrub oak and buckwheat get re-established, the open nature of the vegetation and the slow recovery of the woody species such as manzanita and Ceanothus species (that would serve as a barrier to OHV activity) allows for an increase in off-road vehicle travel. The second threat is increased potential for type conversion of native vegetation.
B. Emergency Determination – Desert Tortoise The risk assessment matrix in Table 5 was used to determine the probability of damage/loss to desert tortoise. Based on the likelihood of habitat damage due to increased OHV access/disturbance and type conversion, the desert tortoise risk determination is: • HIGH (Likely Probability and Moderate Magnitude of Consequences)
The BAER assessment team has determined that an emergency condition does exist to desert tortoise.
C. Treatments to Mitigate the Emergency – Desert Tortoise The BAER assessment team has proposed Forest Closure Treatments that includes installation of barriers, gates, fencing, and vegetation barriers to try to limit the amount of illegal cross-country vehicle use that is expected due to the lack of vegetation. The Forest Closure Treatments will help reduce the risk of death/injury to desert tortoises from vehicles driving off road. It will also help speed the rate of habitat recovery by reducing the risk of spreading and establishing non- native plants.
In addition, the BAER assessment team has proposed a Weed Detection and Rapid Response treatment will reduce the risk of San Bernardino kangaroo rat habitat degradation from non- native invasive plants.
6. Summary of Threatened/Endangered Wildlife Four of the species (southwestern willow flycatcher, least Bell’s vireo, San Bernardino kangaroo rat, and arroyo toad) are wash/riparian species that have evolved with periodic habitat disruptions and the dynamic conditions found in that habitat type. Post-fire watershed response events (e.g., flooding, debris flows, sediment delivery, etc.) will likely affect some of the habitat conditions for a few years after the fire. Left alone without other disturbances, the habitat would recover within 5-10 years. However, where vegetative screening and barriers were lost due to fire, those areas may be subjected to additional impacts from OHVs and people. Additionally, OHV incursions encourage and spread disturbance-tolerant non-native invasive species. Those cumulative effects could have long-term negative consequences for the T/E animals and their
Page 28 habitat. The last of the T/E species, desert tortoise, is not expected to be threatened by post-fire watershed response events but the effects from increased OHV access and lack of vegetative cover and forage does pose a threat.
The proposed BAER treatments of Forest Closure, Weed Detection and Rapid Response, interagency coordination with partners and special use permit holders, and monitoring are critical to protecting the habitat and species from additional post-fire impacts. Appendix C includes Design Features that are to be shared with implementation personnel and cooperators for any activities that will occur in T/E habitat.
7. Water Sources A. Resource Condition Assessment – Water Sources There are a number of developed springs, fiberglass guzzlers, and cement guzzlers within the fire perimeter. Function of water sources is critical to provide water for a number of wildlife species in this dry area. The water source infrastructures represent a substantial government investment over many years. Thirteen of the developed springs that were assessed are at risk of filling with sediment (losing function of providing a water source) or loss of infrastructure due to erosion.
B. Emergency Determination – Water Sources The risk assessment matrix in Table 5 (from Chapter 2520 – Watershed Protection and Management) was used to determine the probability of damage/loss from hazardous waste. The risk determination for losing/compromising the integrity of developed water sources is: • HIGH Risk (Likely Probability and Moderate Magnitude of Consequences)
The BAER assessment team has determined that an emergency condition does exist from exposure to the waste presented by burned fiberglass.
C. Treatments to Mitigate the Emergency –Developed Spring/Guzzler Sediment Deflector Treatment A sediment deflector will be used to protect identified wildlife water structures from potential sediment flow. Treatments could include sediment deflectors (wattles, sandbags, logs, or water bars) or traps constructed by hand above the spring development infrastructure to reduce the amount of sediment entering the water tanks and to protect the infrastructure from erosion/flooding. Volunteers will be recruited from Quail Forever to complete the work under the guidance of the GS-6 biological technician.
8. Hazardous Waste A. Resource Condition Assessment – Hazardous Waste from Fiberglass Guzzlers One fiberglass wildlife water guzzler burned in the fire. As a result of the damage, fiberglass pieces will continue to litter the area posing a threat to animals that might gather pieces for nest/den material.
B. Emergency Determination – Hazardous Waste from Fiberglass Guzzlers The risk assessment matrix in Table 5 (from Chapter 2520 – Watershed Protection and Management) was used to determine the probability of damage/loss from hazardous waste. The hazardous waste risk determination is:
Page 29 • VERY HIGH Risk (Very Likely Probability and Moderate Magnitude of Consequences)
The BAER assessment team has determined that an emergency condition does exist from exposure to the waste presented by burned fiberglass.
C. Treatments to Mitigate the Emergency – Hazardous Waste from Fiberglass Guzzler The proposed treatment is to remove the burned fiberglass guzzler for proper disposal. Removal would require a crew with hand tools and appropriate PPE to disassemble the guzzler and truck it to a landfill for disposal.
9. Abandoned Mines A. Resource Condition Assessment – Abandoned Mines The Blue Cut fire increased the safety hazard of three open mine adits and one vertical ventilation shaft along the Sheep Canyon Road. During the Sheep Fire (2009) BAER implementation, the mine adits were closed with bat-friendly gates and the ventilation shaft was fenced. All features were marked with warning signs.
The burning of vegetation during the Blue Cut fire has made these features clearly visible from the Sheep Canyon Road just above the community of Lytle Creek. The Blue Cut fire burned the warning signs and compromised the fence around the vertical shaft, posing an increased threat to public safety.
B. Emergency Determination – Abandoned Mines The risk assessment matrix in Table 5 (from Chapter 2520 – Watershed Protection and Management) was used to determine the probability of threat to public safety due to exposed mines. The hazardous waste risk determination is: • HIGH Risk (Likely Probability and Moderate Magnitude of Consequences)
The BAER assessment team has determined that an emergency condition does exist to public safety from the abandoned mines.
C. Treatments to Mitigate the Emergency – Abandoned Mines The proposed treatment is to fix the burned fence around the vertical ventilation shaft and replace burned signs at all of the mines.
10. Treatment Effectiveness Monitoring Monitoring the effectiveness of the above-described BAER treatments will be used to determine if additional treatments are needed to protect the T/E habitat and species. This includes monitoring the BAER Forest Closure Treatments, mine closure treatment, and spring/guzzler deflection treatment.
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Page 35 APPENDIX A: DEVELOPED WATER SOURCE CONDITION ASSESSMENT
Spring/ Surveyed Condition Assessment Risk from Post- Proposed Trough/ By* Fire Watershed BAER Guzzler Events Treatment 023W trough RE, DF Dry, spring notebook says it is fed No from valve in station. Capt was not there and other engine crew members did not have knowledge of the spring. 05W guzzler DF, EW, clean, dry, wattles installed after sheep Yes - sediment Install JZ fire seemed to have held some sediment sediment. Need to removed burned deflectors wattles and install new ones 11W trough DF, EW, clean, dry, not connected, pipe located Yes - sediment JZ running up canyon toward spring 02W 02W Tank DF, EW, dry, not sure if it was just a tank for No JZ PCT hikers 11W trough DF, EW, clean, dry, not connected, some tubing Yes - sediment (upper) JZ located running up canyon toward spring 02W 02W Spring DF, EW, damp seep, not much flow. Small Yes - sediment JZ trough nearby was not connected to spring, evidence of tubing was present. Steel pipe running from small trough downslope toward other troughs Spring 03W DF, EW, did not visit spring site but looked at No JZ area. Site is outside burned area and is not threatened from post fire events guzzler 21W DF, EW, fiberglass guzzler, destroyed by fire. Yes Removal JZ Needs to be removed valverne DF, EW, did not visit spring site but looked at No spring JZ area. Site is outside burned area and is not threatened from post fire events trough 05W DF, CG UTL, area is overgrown with riparian Yes - debris Install vegetation. In an unburned section of flows sediment the canyon. May be threatened by deflectors debris flows coming from upstream. blue cut DF, CG UTL, area pretty dry No? spring guzzler 03W DF, CG clean, well maintained, water in catch Yes - debris Install basin. Upper edge was above sediment flows sediment level, potential threat from debris flows deflectors guzzler 02W DF, CG filled with sand, next to wash coming Yes - debris Install off of South bound 15 fwy. Channel flows and sediment moved, wattles may help, needs to be sediment deflectors cleaned. High threat due to proximity to north and bluecut fires.
Page 36 APPENDIX A: DEVELOPED WATER SOURCE CONDITION ASSESSMENT Spring/ Surveyed Condition Assessment Risk from Post- Proposed Trough/ By* Fire Watershed BAER Guzzler Events Treatment guzzler 10W DF, CG clean, in good shape. Fence around it No is coming down, Not sure if fence is needed. No threats from post fire events. Bobcat living in tank. guzzler 25W DF, CG clean, well maintained. No threats No from post fire events guzzler 24W DF, CG clean, well maintained, water in catch No basin. In unburned area. Lots of wildlife sign. No threats from post fire events. guzzler 08W DF, CG clean, well maintained, low threat from Yes - debris and Install debris coming downslope from sediment sediment road/fire above. Wattles may help deflectors keep debris out of guzzler. guzzler 07W not visited, looks like may need wattles Yes - sediment Install based on topo map sediment deflectors guzzler 09W Kim B said this one silts in and wattles Yes - sediment Install may help. Not visited, looks like may sediment need wattles based on topo map deflectors guzzler 18W not visited, looks like may need wattles Yes - sediment Install based on topo map sediment deflectors guzzler 16W not visited, access through private trough 13W not visited, access through private trough 12W Suppressi Spring is in the interior of fire. No Yes - sediment Install and Spring on Repair suppression damage. High fire sediment 1W (Tunnel team intensity has damaged riparian area deflectors fault spring) guzzler 05W Suppressi High severity fire, no suppression Yes - sediment Install (Lone Pine on Repair damage. Wattles up slope of the sediment Guzzler) team guzzler have burned deflectors guzzler 11W Suppressi Undamaged by fire. No suppression No (Crowder) on Repair repair needed. team trough 14W Suppressi Undamaged. Outside the fire. No Lone Pine on Repair Spring team Trough Clyde Spring Suppressi Undamaged. Outside the fire. No on Repair team *DF= Drew Farr, RE= Robin Eliason, EW= Emma Williams, CG= Cesar Garcia
Page 37 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
Summary The following Forest Service Sensitive species are known from or have the potential to occur in/near the fire: two-striped garter snake, northern three-lined boa, southern California legless lizard, San Bernardino mountain kingsnake, San Bernardino ringneck snake, San Gabriel Mountains slender salamander, California spotted owl, migrant willow flycatcher, fringed myotis, pallid bat, Townsend’s big-eared bat, and San Gabriel mountains bighorn sheep. Western pond turtles historically occurred in Lone Pine Canyon.
Watchlist species known from the Blue Cut Fire area include: long-legged myotis, long-eared myotis, silver-haired bat, hoary bat, coast horned lizard, common poorwill, western bonneted bat, western small-footed bat, Cooper’s hawk, osprey, golden eagle, prairie falcon, peregrine falcon, long-eared owl, common yellowthroat, gray flycatcher, hermit thrush, Swainson’s thrush, purple martin, Lawrence’s goldfinch, MacGillivray’s warbler, olive-sided flycatcher, Bell’s sparrow, warbling vireo, solitary vireo, yellow warbler, yellow-headed blackbird, yellow-breasted chat, American badger, mountain lion, and San Diego pocket mouse.
Non-natives known from the Blue Cut fire area include brown-headed cowbirds, bullfrogs, European starling, and red-eared slider. Sport fish existed in Lost Lake where some game fish were stocked. No other sport fish exist in the Blue Cut fire area.
The above-mentioned species and their habitats within the fire perimeter have been affected by the fire and suppression activities. The habitats and species occurrences are at risk to further losses, disturbances, and habitat degradation from post-fire watershed events. For aquatic/riparian species, these impacts include reduced water quality and changes in water chemistry due to ash delivery, hazardous materials, and changes in water temperature from loss of canopy shading; scouring of riparian/aquatic vegetation and changes in streambed/pool habitat due to debris flows and sediment delivery; flushing of species during flood events downstream and the potential for localized extirpations due to barriers that prevent re-colonization.
For all species, there is a concern that until enough vegetative recovery (3-5 years or longer) has occurred to deter off-road vehicle use, habitat degradation may occur. Increased access and visibility due to lack of vegetative cover will result in habitat degradation, disturbance of species, and increased risk of collection for species such as tortoises, tadpoles, fish, etc.
Another concern for all species is the spread of non-native plants and animals into rare species and general wildlife habitat. Post-fire events may facilitate the spread of non-native aquatic species into previously unoccupied habitats. This concern is elevated for streams with special status species where high water flows have the potential for washing non-native aquatic species into downstream reaches beyond their original location.
The greatest risk to all wildlife habitats and species are the cumulative effects of fire, post-fire watershed impacts, and the potential long-term disturbance and habitat impacts from increased access by people and driving off of official system roads/trails. It is expected that a minimum of 3-5 years may be needed for this initial and critical phase of vegetation recovery.
Page 38 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
General Wildlife Habitat Condition Assessment: Situated between urban areas and desert habitat, the San Bernardino Mountains function as an island of wildlife habitat. The fire area supports multiple vegetative communities and a wide range of native wildlife species. As vegetation recovers, wildlife in the fire area will once again recolonize. Species dependent on mixed conifer stands will be affected the longest since it will be decades before timbered areas will be established again. Until vegetation in the area recovers, native wildlife species within the fire area will experience a shortage of shelter and escape. Some species may have difficulty finding adequate food supplies and breeding sites, including many species of neotropical migratory birds that nest in this area.
Stopover riparian habitat for migrating birds continues to decline in availability and quality. Stopover habitat is critical for foraging and resting and when it is not available, survivorship for all species of migrating birds is affected. The fire has affected availability of chaparral, riparian, and conifer habitat for migratory birds. The predicted watershed responses of flooding, debris flows, and sedimentation will likely hinder recovery of riparian vegetation for several years. As watersheds stabilize over the next 3-5 years, riparian vegetation should recover and once again provide suitable habitat for nesting and foraging birds.
Human use of the burn area is one of the primary concerns related to post-fire recovery of habitat and species. In much of the burn area, shrubs and trees that may have once screened areas from public view are now gone. People traveling roads and trails are now able to see areas that were previously undetected. Without dense vegetation to block their access, there is an increased risk of individuals seeking out new areas to explore by foot or by using motorcycles, 4-wheel drives, and bicycles.
Without vegetative screening to block the view and impede access, dispersed recreation activities (e.g., off-road driving and biking, fishing, picnicking, waterplay, camping, hiking, etc.) will increase. Habitats at greatest risk include streams, ponds and wet meadows. Changes in access and dispersed recreation use will hinder vegetative recovery, result in higher disturbance to already-stressed animals, increase the risk of rare animals (such as desert tortoise) being collected for pets, and increase the risk of introduction/spread of non-native plants and animals.
Within the fire area, there are documented occurrences of non-native species with the potential to affect native species, including some of the TES species. Many of these non-native animals are riparian associates (bass, bluegill, mosquitofish, carp, koi, goldfish, bullfrog, and red-eared sliders). Others, like European starling and brown-headed cowbird, compete with or displace native birds. Non-native species compete for resources, displace native animals, modify habitats, and pose predation threats to native fish, amphibians and reptiles.
Sport Fisheries Habitat Condition Assessment The only site in the fire area where fishing occurs was Lost Lake where there were a number of different stocked or dumped non-native fish species. This was a popular recreation fishing site. However, the extended drought had lowered the water level progressively in late 2015. By late- summer 2016, Lost Lake was essentially dry and lacked fish. It is possible that seismic activity or nearby well drilling could have also contributed to Lost Lake going dry but neither of those have been investigated or validated.
Page 39 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
The Blue Cut BAER team predicted some post-fire sediment delivery to Lost Lake. Given the current conditions, no effects to sport fisheries are expected. If Lost Lake fills up and fish are re- introduced, post-fire sediment may affect water quality and fish during/after storm events even for a few years post-fire.
Condition Assessments - Forest Service Sensitive Fish Santa Ana Speckled Dace Condition Assessment: Santa Ana speckled dace (Rhinichthys osculus) is a Sensitive species. This taxon occupies only remnants of its historical range, with a limited distribution in the headwaters of the Santa Ana and San Gabriel Rivers. On the San Bernardino National Forest, small Santa Ana speckled dace populations are reported from the main stem of Lytle Creek, Cajon Wash, Lone Pine Canyon, Strawberry Creek, Plunge Creek, City Creek, Mill Creek (i.e., a population was found just downstream of the San Bernardino National Forest boundary in August 1997, but has not been observed since flash flood event in September 1997 and the South Fork of the San Jacinto River. Flood control structures that do not allow fish migration have isolated forest populations.
Santa Ana speckled dace inhabits a number of stream and channel types, small springs, brooks, and pools in intermittent streams and large rivers. In general, this species requires abundant cover and well-oxygenated clear water flowing over shallow cobble and gravel riffles. The preferred summer water temperature is 63 º F–68 º F. In one study for the San Gabriel River, adult Santa Ana speckled dace show a preference for gravel substrate and a lesser preference for cobble substrate, a preference for flowing habitats (riffle, run, glide), and variability in depth preference. Juveniles show a preference for sand and gravel, pool and riffle habitat. In this same study, fry were found exclusively in edgewater habitat over silt at depths of less than 17 cm where there was no measurable.
Maturation is most likely to occur by two years. Spawning takes place throughout the summer and peaks during June and July. Rising water temperatures and flows in intermittent streams may induce spawning. Spawning occurs over rocks and gravel, where the larvae remain until emerging and moving to warm shallow areas in the stream. Speckled dace appear to be moderately tolerant of high water temperatures and low dissolved oxygen. Recruitment success can be low during high-flow years. Flooding contributes to the downstream dispersal of the species. Santa Ana speckled dace generally feed on small benthic invertebrates such as larvae of hydropsychid caddisflies, baetid mayflies, and chironomid and simuliid midges.
Lytle Creek and Cajon Creek/Wash may experience and loss of water quality (ash, sediment, debris) especially during the first storms, some flooding, and some localized debris, depending on the size of post-fire events. Dace in Cajon Creek/Wash may be more threatened than those in Lytle Creek. See the discussion under San Bernardino kangaroo rat for Lytle Creek and under arroyo toad for Cajon Creek/Wash.
Condition Assessments - Forest Service Sensitive Amphibians San Gabriel Mountain Slender Salamander Condition Assessment: San Gabriel Mountain Slender Salamander (Batrachoseps gabrieli) is known from only a few localities, all in the eastern San Gabriel Mountains including Lytle Creek in the Blue Cut fire area.
Page 40 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
San Gabriel Mountain slender salamander has been found on northwest-facing talus slopes or near water in mixed hardwood-conifer forest habitats containing oaks (Quercus spp.), pines (Pinus spp.), big cone Douglas-fir (Pseudotsuga macrocarpa), white fir (Abies concolor), California laurel (Umbellularia californica), Oregon big-leaf maple (Acer macrophyllum), and incense cedar (Calocedrus decurrens). The known elevational range of this salamander is 3,800–7,780 feet. When active near the surface, San Gabriel Mountain slender salamander typically occurs in talus and under large rocks, rotting logs, downed tree limbs, and bark. Specimens have been collected within 50 feet of a stream.
Surface activity of San Gabriel Mountain slender salamander is probably limited to a few months in the winter and early spring. Individuals are relatively common during February and March near the surface, even when soil surface temperature is just above freezing. Presumably, these salamanders move deep within the talus, where conditions are cooler and moister, during the dry months of summer and early fall.
If San Gabriel Mountain slender salamander conforms to patterns exhibited by Tehachapi slender salamander (Batrachoseps stebbinsi), which resembles it and is also a talus dweller, it forages in leaf litter and under bark and rotten logs for food. The two species' diets may also be similar, consisting of small spiders, mites, and various insects.
Eggs and larval salamanders in the aquatic systems could be affected by high flows, scouring, sediment loading and/or debris torrents. Sediment delivery and debris flows can reduce water quality, silt egg-laying sites and reduce prey availability. Water quality may be affected by increases in sediment delivery, ash deposition, debris flows, and changes in turbidity. Larval salamanders can be killed if buried or suffocated by sediment. Excessive inputs of ash may cause localized changes in water pH and degrade conditions. As adults, this species is found in rocky areas and talas slopes.
Adult salamanders and their habitat may be impacted by rock slides and debris flows. Depending on the size of post-fire events, Lytle Creek may experience some localized debris flows and loss of water quality. Effects to salamanders would vary depending on the life stage and timing of post-fire watershed response events. Adults in the upland will experience less risk than eggs or larval salamanders tied to the aquatic systems.
Condition Assessments - Forest Service Sensitive Reptiles Two-Striped Garter Snake Condition Assessment: The two-striped garter snake is a Forest Service Sensitive species. This species inhabits streams and ponds and preys on aquatic invertebrates, tadpoles, small fish, frogs, and toads. They are expected to occur in all watersheds within the burn area. Two-striped garter snakes are known from the riparian areas within the fire area.
It is likely that individual two-striped garter snakes will be injured or killed during debris flows, rockfalls/landslides, and flooding. The level of direct impacts would vary depending on time of year of the storm event and the location of the snakes in the landscape relative to the flows and slide activity.
Page 41 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
Prior to the fire, some of the areas occupied by two-striped garter snakes were shielded by dense vegetation. The visual and physical barriers created by the dense vegetation helped deter recreation and illegal OHV use in the area. With vegetation along roads, trails and streams now gone in places, the riparian/aquatic habitat is at high risk of increased disturbance associated with waterplay and dispersed recreation. Waterplay and dispersed recreation can result in the following impacts to two-striped garter snakes and their habitat: harassment, injury, death, increased risk of collection, decreased water quality and impacts to streambanks and riparian vegetation. Pedestrian, bicycle and OHV traffic can delay vegetative recovery and stream restoration. Occupied areas are also at risk of loss of habitat quality if non-native plants spread or become established in the riparian/aquatic habitat.
In summary, primary concerns for the two-striped garter snake are associated with the potential for individuals to be injured or killed by debris flows, floods and rock slides. The prey base for this species is compromised and this could result in additional stress to foraging individuals. Occupied areas are also at risk for the introduction of non-native plants and animals that would further degrade habitat quality and impact the snake through predation, competition and disease introduction. The loss of vegetative barriers/screens and the resulting recreation use presents a risk to the two-striped garter snake and its habitat.
Sensitive Terrestrial Reptiles Condition Assessment: Forest Service Sensitive reptiles known from within the fire area include the following: San Bernardino mountain kingsnake, San Bernardino ringneck snake, orange-throated whiptail, and southern California legless lizard.
All of these species are at increased risk of disturbance, injury or mortality. With cover, foraging and reproductive habitat either reduced or completely removed, these species are especially vulnerable to additional environmental stressors. Individuals and their habitat may be impacted by rock slides, debris flows and flooding. Anthropogenic stressors will most likely be associated with recreation activities.
Prior to the fire, many of the areas occupied by these species were shielded by dense vegetation. The visual and physical barriers created by the dense vegetation helped deter recreation and illegal OHV use in the area. With vegetation along roads, trails and streams now gone, suitable habitat is at high risk of increased disturbance associated with dispersed recreation. Dispersed recreation can result in the following impacts to these species and their habitat: harassment, injury, death, increased risk of collection, decreased water quality and impacts to streambanks and riparian vegetation. Pedestrian, bicycle and OHV traffic can delay vegetative recovery and stream restoration.
An increase in the abundance and distribution of non-native plant and wildlife species is anticipated and will negatively impact habitat and populations of sensitive reptile species. Vehicles, bicycles, horses and pedestrian traffic may increase the potential for introduction of non-native plants into previously unoccupied areas.
Page 42 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
Condition Assessments – Forest Service Sensitive Birds California Spotted Owl Condition Assessment: California spotted owls are a Forest Service Sensitive species. Spotted owls are found in mature forests, typically where there is a dense, multi-layered canopy. They use a wide range of wooded and forested habitats and nest stands often have a well-developed hardwood understory. However, some high-elevation territories (above 6,500 feet) consist primarily or solely of conifers and some low-elevation territories (below 3,000 feet) are found in pure hardwood stands. At lower elevations, they occur in coast live oak, alder, and sycamore woodlands along riparian areas. At higher elevations, they occur in mixed conifer/hardwood forests, and are often associated with big cone Douglas-fir and black oak.
California spotted owls are a territorial species with large acreage requirements (at least 300 acres of mature forest per pair), spotted owls in southern California are clustered in disjunct mountain and foothill areas where suitable habitat exists. These clusters are often surrounded by large areas of unsuitable habitat.
Spotted owl response to fire in southern California is not well documented. While early seral habitats may provide suitable foraging habitat, this will be of little benefit to birds if suitable roosting and nesting habitat is not available in close proximity. Understory burns in forested stands may benefit spotted owls by opening up additional foraging habitat. If mortality in the overstory reduces canopy closure, this could decrease the suitability of nesting habitat.
There is one spotted owl territory (Upper Lone Pine Canyon – SB007) that has Protected Activity Center and Home Range Core mapped in the fire perimeter (see the map packet). There is also mapped Suitable habitat within the fire boundary.
Mapped Owl Habitat Soil Burn Severity Acres Upper Lone Pine Canyon (SB007) Outside the Fire Perimeter 288.30 Unburned/Very Low 20.45 Low 48.80 Moderate 107.32 High 56.31 TOTAL for SB007 572.18 Mapped Suitable Habitat Unburned/Very Low 1.85 Low 108.62 Moderate 344.38 High 101.10
The Lone Pine Canyon Nest Stand did not burn; it is outside the fire perimeter. Many of the bigcone Douglas fir trees along 3N31Y had brown needles but did not appear to have had the trunks burned enough to girdle the trees. It is possible that the needles died from heat and the
Page 43 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire trees may not be dead. It is recommended that the trees be re-assessed by a forester next spring to determine if they are alive and not assumed that they are dead.
Page 44 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
Page 45 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
SB007 Nest Stand
Mapped SB007 spotted owl habitat that burned in the 2009 Sheep Fire
Page 46 APPENDIX B: Other Wildlife Species of Interest Affected by the Blue Cut Fire
Condition Assessments - Mammals Sensitive Bat Condition Assessment: The Blue Cut Fire area provides habitat for two Forest Service Sensitive bats: Townsend’s big-eared bat, fringed bat and pallid bat. A number of other bat species not included on the Forest Service Sensitive list are known from the fire area and are as follows: western small-footed myotis, long-eared myotis, little brown myotis, long-legged myotis, Yuma myotis, western red bat, spotted bat, western bonneted bat, hoary bat, and silver- haired bat.
Tree-roosting bats likely experienced injury or mortality as a direct result of the fire. All bat species have experienced a loss of foraging habitat and a modified prey base.
No abandoned mines are recorded in the fire area. Fire can eliminate vegetation that previously concealed mine adits from view or deterred access. In those cases, it takes years for vegetation to recover enough to provide screening for these mines. If there are mine adits with bat habitat that are not known, they could be affected. Other than that, post-fire watershed responses are unlikely to directly affect bats.
Page 47 APPENDIX C: BAER Treatment Design Features
Design Features were developed for BAER treatments that will be implemented in Threatened and Endangered species habitat. These measures will also be given to cooperators (e.g., utilities, railroads, special use permittees, Caltrans, SCE, S. CA gas, County of San Bernardino, Union Pacific Railroad, BNSF railroad, Kinder Morgan, LA DWP, etc.) who propose to implement emergency actions on NFS lands. These measures were included in the Emergency Consultation with U.S. Fish and Wildlife Service initiated by the SBNF for emergency actions related to the Blue Cut fire.
Design Features for Threatened/Endangered Species/Habitat Protection – Slender-horned spineflower, arroyo toad, San Bernardino kangaroo rat, southwestern willow flycatcher, least Bell’s vireo, and desert tortoise
• Where work is conducted in or near T/E habitat or Critical Habitat, a biological monitor will be present. • A biological will be present for work planned in occupied or Critical Habitat for arroyo toad, San Bernardino kangaroo rat, and desert tortoise. To protect animals in burrows, the biologist will work with crews to avoid equipment use and walking in habitat suitable for burrowing by arroyo toad, San Bernardino kangaroo rat, and desert tortoise. Pre-work surveys will look for active burrows and mark them for avoidance. Monitors will be on site to ensure that avoidance happens and to watch for individuals. • Where work is conducted where water is present, a biologist will survey for arroyo toad tadpoles and egg masses. If any are found, those areas will be avoided. • Vehicles will avoid areas that have water present. If crossings are necessary, the biologist will identify a crossing with the least likelihood of affecting aquatic habitat and water quality. The number of vehicles crossing wet crossings should be limited to the greatest extent possible. • Where work is planned in suitable habitat for southwestern willow flycatcher or least Bell’s vireo, a biologist will flag suitable habitat and guide crews to minimize activities that would degrade habitat conditions (riparian vegetation). • Following the Forest Service guidelines, all vehicles and equipment coming on to NFS lands will be washed and inspected to minimize the risk of introducing and transporting non-native species to the site. • Project administrators, inspectors, and personnel will be provided information on rare animals, rare plants, and weeds within project areas and provided direction for what to do if those species are encountered (including notification of a district biologist or botanist). • Observations of any sensitive species or their diagnostic signs during project activities will be conveyed to the project field supervisor the day observed. The field supervisor will convey this information to the District Biologist. • Nighttime (after dusk and before dawn) work (and use of artificial lighting) will not be permitted unless under special permission from the Forest Service. • No side-casting of materials is permitted. • Temporary overburden piles would be stored in road bed or other previously-disturbed site/clearing. Exceptions would require Forest Service approval. • Pursuant to Forest Service Manual (FSM) Section 2081.03 guidelines for weed control, all equipment, vehicles, and tools (e.g., augers, chain saws, hand clippers, pruners, etc.)
Page 48 APPENDIX C: BAER Treatment Design Features
will be washed with a high pressure water/air system before entering the SBNF and before moving to new project sites. A wash log will be kept with the crew at all times. If a biological monitor is present, they will also retain a copy of the wash log. • All material from off-site sources (fill, base material, fill, rock and gravel, straw, mulch, etc.) used for erosion control, rehabilitation of temporary routes/landings, and/or route maintenance must be certified weed-free (S-6, LMP Part 3, p. 5). Fill material will be dry before transporting to the site to minimize the risk of introducing non-native aquatic plants, pathogens, and invertebrates (e.g., snails, mussels, chytrid, etc.). • Project personnel will not bring pets to the work sites. • Feeding of all wildlife is prohibited. • Collecting of any wildlife or plants is prohibited. • Trash and food shall be contained in closed containers and removed from the job site daily to reduce attractiveness to opportunistic wildlife species. All construction debris will be removed at the end of the job. • If bird nests are found during project implementation, activities will cease in the immediate area until the Project/District Biologist is notified. The biologist will determine whether activities may resume or whether to stop activities until young have fledged and the nest is vacant (as determined by the project biologist). • Crews will not intentionally injure or kill wildlife species (including snakes). Instead, animals will be allowed to leave the work area before work resumes. • The project manager will coordinate with the biologist to minimize disturbance of existing downed logs and rock outcrops that are suitable for rare species. If disturbance is unavoidable, a biologist may need to be present to monitor for sensitive species during disturbance of the habitat. Equipment, supplies, materials, and soil/gravel, etc. will not be stored on or against logs or rock outcrops.
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