2020 ArchieFire Report FEMA ETART Extended Report.pdf

Archie Creek Fire Erosion Threat Assessment/Reduction Team (ETART) Extended Report

December 2020

ETART Extended Report – Archie Creek Fire

DR-4562-OR | EROSION THREAT ASSESSMENT/REDUCTION TEAM

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DR-4562-OR – December 2020 i

Table of Contents

Executive Summary

1. Overview

1.1. Burned Area Characterization

1.2. Post-fire Watershed Condition

2. Risk Assessment and Recommendations

2.1. Human Life and Safety Summary

2.2. Property Summary

2.3. Natural Resources Summary

2.4. Cultural Resources Summary

3. Monitoring and Management Recommendations

3.1. Watershed Response and Hydrologic Analysis - Monitoring Recommendations

3.2. Geologic Hazards - Management Recommendations

3.3. Road Management Recommendations

3.4. Fish/Aquatic Habitat - Management Recommendations and Monitoring

Resource Reports

1. Weeds Specialist Report

1.1. Summary

1.2. Resource Condition and Setting

1.3. Assessment Methodology - Field Evaluations and Modeling

1.4. Results of Field Work and Modeling

1.5. Risk Assessment

1.6. Recommended Response Actions

1.7. Best Management Practices Recommendations

1.8. Recommended Monitoring

1.9. References

2. Engineering Report

2.1. Objectives

2.2. Values at Risk

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2.3. Observations

2.4. Reconnaissance Methodology and Results

2.5. Findings

2.6. Recommendations

2.7. References

3. Heritage and Cultural Resources

3.1. Setting

3.2. Background

3.3. Critical Values and Proposed Treatment for Cultural Resources on NFS lands under

BAER

3.4. Assessment Methodology

4. Soil Resources

4.1. Summary

4.2. Resource Condition and Setting

4.3. Assessment Methodology

4.4. Findings

4.5. Risk Assessment

4.6. Recommendations

5. Hydrology Resources

5.1. Summary

5.2. Critical Values

5.3. Resource Condition and Setting

5.4. Risk Assessment

5.5. Assessment Methodology – Field and Modeling

5.6. Findings

5.7. Recommendations

5.8. References

6. Geologic Hazards

6.1. Introduction

6.2. Assessment Methodology

6.3. Findings

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6.4. Recommendations

6.5. Mitigation and Further Evaluation

6.6. References

7. Hazard Trees

7.1. Objectives

7.2. Danger/Hazard Trees Described

7.3. Recommendations

7.4. Danger Tree Guidelines

7.5. References

8. Fish and Wildlife Resources

8.1. Objectives

8.2. Assessment Methodology (field and modeling)

8.3. Resource Setting

8.4. Critical Values, Results, Risk Assessment, and Recommended Response Actions

8.5. Recommended Monitoring

9. Archie Creek ETART Members

Appendix A – Road Treatment Cost Estimates

Appendix B – Supporting Weeds Information, Treatment Design, and Cost Estimates

Appendix C – Supporting Soil Information

Appendix D – Supporting Geologic Hazards Information

Appendix E – Supporting Hazard Tree Information

Appendix F – Fish and Wildlife Values at Risk Table

Appendix G - Supporting Hydrology Information

DR-4562-OR – December 2020 1

Executive Summary This report summarizes a rapid characterization of post-fire conditions resulting from the Archie Creek Fire and identifies critical values potentially at risk from threats commonly associated with burned areas. In addition, the ETART assessment of drinking water threats from the Archie Creek Fire and other fires are captured in the ETART Water Quality/Drinking Water Supply Resource Report. The area of interest for this report consists of non-federal lands within and downstream of the Archie Creek Fire perimeter. Critical values include human life and safety; improved properties/assets such as roads, bridges, buildings and water systems; important natural resources (soil productivity, water quality and municipal water sources, habitats for wildlife and fish); and cultural resources. Threats that exist or are recognized to amplify in a post-fire setting include accelerated soil erosion and hillslope water runoff that results in increased sediment transport, high stream flows, floods or debris flows; landslides and rock fall; hazard trees; mobilization of hazardous materials; and expansion of invasive or noxious plants. This report does not include an assessment of water quality and water systems that provide safe, clean drinking water. Refer to the ETART Water Quality/Drinking Water Supply Resource Report for information on post-fire threats and response actions for these values.

The essential findings of this evaluation are: 1) to identify where emergency conditions exist as defined by critical values at unacceptable risk from imminent post-fire threats; and 2) to recommend emergency response actions that reduce risk or minimize impacts to critical values. In addition to the emergency response actions, the data, analysis and conclusions supporting this report can be used to develop restoration opportunities leading to long-term recovery of the fire-damaged landscape. Multiple “Specialist Reports” encompassing soils, hydrology and water quality, engineering, fish and wildlife, botany and cultural were used to complete this assessment.

The 2020 fire season in Oregon State affected lands across all jurisdictions and ownerships: tribal, federal, state, local and private. Fires on federal and tribal lands are assessed through the U.S.

Forest Service (USFS) Burned Area Emergency Response (BAER) or Department of Interior (DOI) Emergency Stabilization and Rehabilitation (ESR) programs. Given the size and severity of the fires’ impacts to state, local and private lands throughout Oregon, the State of Oregon requested the Federal Emergency Management Agency (FEMA) form a multi-jurisdiction assessment team to assess the state, local and private lands of several fires. FEMA coordinated with Oregon Emergency Management (ODF) and Department of Forestry (ODF), National Weather Service (NWS), U.S. Army Corps of Engineers (USACE) and the USFS to staff the Erosion Threat Assessment and Reduction Team (ETART) to evaluate the fire-affected state and private lands.

The team used the USFS BAER and DOI Emergency Stabilization & Rehabilitation (ESR) assessments for several fires, which established the foundation for the ETART and allowed for comprehensive evaluation of all lands burned within the fires.

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2020 Oregon ETART is comprised of personnel from Clackamas County Soil and Water Conservation District (SWCD), Lane County, Linn County, Marion County SWCD, West Multnomah SWCD, OR Department of Environmental Quality (DEQ), OR Department of Fish & Wildlife (ODFW), ODF, OR Department of Geology and Mineral Industries (DOGAMI), OR Department of Transportation (ODOT), OR Water Resources Department (OWRD), Bureau of Land Management (BLM), Environmental Protection Agency (EPA), FEMA, USFS, U.S. Geological Survey (USGS), NWS and the Natural Resources Conservation Service (NRCS). These resource specialists completed the assessments while safely managing COVID-related protections, navigating interagency data sharing barriers, operating in a hazardous post-fire field environment and working across a broad geographic area.

ETART members went above and beyond the demands of their normal duties to carry out critical emergency assessments in service of local communities.

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1. Overview

1.1. Burned Area Characterization

Fire Name: Archie Creek

State: Oregon

Fire Number: OR-UPF-000436

County: Douglas

Date Fire Started: September 8, 2020

Date Fire Contained: November 16, 2020

Suppression Cost: $40,000,000 (estimate, ICS-209 dated 10/22/2020)

Figure 1. Land Ownership - Archie Creek Fire

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The Archie Creek Fire was detected on September 8, 2020, east of Glide, Oregon, in the North Umpqua River drainage during a strong east wind event that passed through the area. The fire merged with the Star Mountain Fire in the Susan Creek area and burned roughly 68,000 acres in one day. On September 9th the fire progressed to 110,000 acres; 109 homes were destroyed, and nine other structures were damage or destroyed over a 2-day burning period. The fire burned across multiple land ownerships, including the Umpqua National Forest, BLM, private timber land, and through the communities of Rock Creek and Steamboat along both sides of the North Umpqua River and the Rogue-Umpqua Scenic Highway. (Figure 1 and Table 1.)

Table 1. Archie Fire Total Acres Burned – 131,596a (based on post-fire analysis perimeter)

Ownership Acres Sq.Mi. Percent

Private 64,676 101 49%

State 39 <1 <1%

Federal 66,881 105 51%

Total 131,596 206 a: the burned area lies entirely within Douglas County, Oregon.

1.1.1. CLIMATE

The burned area is a region that experiences precipitation patterns of frontal rain/snowstorms and occasional summer convective thunderstorms. Precipitation in the area primarily occurs between October and April as multiple day frontal storms, averaging between 40 and 100 inches annually.

The upper regions of the burned area are within the transient snow zone (2,000-5,000 feet elevation). The North Umpqua River gorge and its tributary valleys are below 2000 feet and within the rain zone. Late winter rain-on-snow events can result in extreme flood events. Peak flows can be much higher in the lower tributaries where rainfall and rain-on-snow events are not moderated by the storage capacity of the underlying bedrock, as is the case with streams in the High Cascades geology within the transient snow zone. Wetting rains fell over the western part of the fire area on September 18th, with some areas receiving about 0.25 inch of precipitation. Field reconnaissance reported no observations of overland flow or erosion concerns.

La Niña conditions are present in the tropical Pacific, with an approximately 85% chance of lasting through the winter. Forecasters predict this La Niña will be on the stronger side and peak November through January, with higher than normal precipitation and snowpack.

1.1.2. GEOLOGIC TYPES

The burned area lies within the Western Cascade province of the Oregon Cascade Range, which is characterized by older volcanic rocks, generally steep slopes, and large ancient landslide deposits.

The bedrock geology is primarily comprised of Pliocene to Quaternary igneous extrusive rocks:

basalt, basaltic andesite, dacite, and rhyolite. In general, the landscape shape and surficial deposits consist of unconsolidated alluvium, terrace deposits, fluvial glacial, glacial till, rockslide, landslide

DR-4562-OR – December 2020 5 and debris flow deposits. Weathered rocks in this province support relatively high rates of runoff and erosion. Consequently, mass wasting processes associated with steep mountain slopes include rapidly moving, shallow-seated debris avalanches, debris slides and debris flows. Landslides have been mapped by the State of Oregon Department of Geology and Minerals Industries (DOGAMI), with these features occurring primarily in a tuff and sedimentary geology that is a minor component along the western border of the area.

1.1.3. DOMINANT SOILS

Dominant soils originate from andesites to basalts, as well as minor areas of weathered red breccia, highly weathered breccias, tuffs, and welded tuffs. Outcrops with exposed rocks are common throughout the area. Soils tend to be shallow to moderately deep, depth to bedrock less than 3 feet up to 8 feet. Surface soil textures range from loamy sands, sandy loams, loams and clay loams with varying amounts of gravel and rock content, generally increasing with depth. These soils are moderately well to well drained with rapid to moderate permeability and minimal water-holding (retention). One-quarter (25%) of the fire area has very steep slopes of 60 to 100 percent or more.

Primary concerns on the steep slopes are the potential severe surface erosion and for shallow debris slides. Soil textures are mainly very gravelly to extremely gravelly loams and clay loams.

1.1.4. VEGETATION TYPES

Forested areas are primarily Douglas-fir, but with lesser components of incense cedar and western hemlock. Scattered throughout uplands are dry meadows, rock balds and steep rocky slopes dominated by Pacific madrone, Oregon white oak and various grasses. These dry meadows provide habitat for several rare and endemic species. Riparian corridors are hardwood-dominated with tree cover provided by alder and bigleaf maple, with various willow species growing along and within streams. Occasional forested wetlands are also present within riparian corridors. The western extent of the fire, both north and south of the river corridor, are comprised of a patchwork of oak woodlands and meadows used for commercial livestock grazing (cattle and sheep). Oak woodlands are Oregon white oak with an understory of poison oak, oceanspray and other drought-tolerant shrubs. Native and nonnative pasture grasses, including California oatgrass, perennial ryegrass and orchard-grass dominate meadows used for livestock grazing. Although relatively small in area, wet meadows and emergent wetlands occur throughout the burned area with a variety of species ranging from common pasture grasses to common cattail, slough sedge and smallfruit bulrush.

There are several known populations of noxious weeds that have been treated with chemical herbicide for decades. These include scotch broom, Himalayan blackberry, English holly, English hawthorn, slender false brome, bull thistle, Canada thistle, St. John’s wort, meadow knapweed, tansy ragwort and medusahead.

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1.1.5. WATERSHEDS AND STREAMS

The Archie Creek Fire burned within 17 subwatersheds, the heaviest impacted being Lower Rock Creek, East Fork Rock Creek and Susan Creek-North Umpqua (Table 2, Figure 2). The fire burned both north and south of the North Umpqua River within the area designated as a National Wild and Scenic River. There are 968 miles of streams, (255 miles perennial and 681 intermittent) within the fire perimeter, including about 17 miles of Designated Critical Habitat for Oregon Coast Coho and 18 miles of suitable occupied habitat for Coho. The North Umpqua and its tributaries are listed on Oregon DEQ’s 303(d) list of impaired streams for water temperature.

Table 1. Affected Watersheds – Archie Creek Fire (6th Level Hydrologic Unit Name)

Watershed Name Total Acres Acres Burned % Burned

Lower Canton Creek 34,601 7,410 21

Lower Steamboat Creek 33,115 61 0

Panther Creek 24,325 3,961 16

Apple Creek-North Umpqua River 23,453 5,515 24

Williams Creek-North Umpqua River 24,799 20,561 83

Thunder Creek-North Unpqua River 33,164 24,861 75

Susan Creek-North Umpqua River 33,978 32,068 94

Upper Rock Creek 47,658 15,548 33

East Fork Rock Creek 28,619 27,407 96

Lower Rock Creek 49,091 49,091 100

Emile Creek 161 26 16

Middle Little River 31 26 84

Lower Little River 15 13 87

Bradley Creek-North Umpqua River 11,352 8,632 76

Headwaters Calapooya Creek 19,428 5,283 27

Hinkle Creek-Calapooya Creek 23,497 11,400 49

Gassy Creek-Calapooya Creek 25,460 2,618 10

Total 412,747 214,481

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Figure 2. Watersheds Percent Area Burned – Archie Creek Fire

Table 3. Road Miles by Ownership Designation within Fire Perimeter

Table 4. Miles of Stream within Fire Perimeter by Type

Owner Designation Milesa Stream Type Miles by Typeb

Bureau of Land Management 295.1 Perennial 255

County Route 5.1 Intermittent 681

Forest Service 109.3 Ephemeral 1

Other State Route (e.g., State Park) 0.8 Other 31

Private Route 511.2

State Highway 16.8

Unknown 1.7

Total Miles 940.0 a: Does not account for priority travel routes below the fire perimeter that may be a “Value” or threatened by flooding or debris flows.

b: Does not account for streams below the fire perimeter that may be a “Value” as domestic or municipal source water, or for aquatic habitat.

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1.2. Post-fire Watershed Condition

1.2.1. SOIL BURN SEVERITY (SBS):

The post-fire watershed conditions are mostly driven by fire behavior, which is largely a function of pre-fire fuel conditions (vegetation types, volumes, arrangement and moisture content) as influenced by weather and topography. Soil Burn Severity (SBS) is the fundamental post-fire factor for evaluating changes in soil processes and hydrologic function, which are used to evaluate watershed response, identify post-fire threats and assess the level of risk to critical values.

Prior to the ETART effort, the Forest Service produced a Soil Burn Severity (SBS) map as part of their Archie Creek BAER Assessment (Figure 3). The Forest Service SBS mapping did not field-validate soil conditions on private or state lands. The ETART soils team completed soil burn severity validation on state and private lands with on-the-ground data collection and visual observations (Table 5).

Table 5. Soil Burn Severity (SBS) Acres.

Soil Burn Severity Class

All Lands Federal Lands Local Lands Private Lands State Lands

Acres % Acres % Acres % Acres % Acres %

High 43,251 33% 22,384 52% 20,867 48% 0 0 43,251 33%

Moderate 57,900 44% 26,535 46% 31,265 54% 10 <1% 57,900 44%

Low 18,681 14% 10,741 58% 7,911 42% 29 <1% 18,681 14%

Unburned 11,692 9% 7,178 61% 4,514 39% 0 <1% 11,692 9%

Total 131,524 66,838 64,557 39 131,524

Though the Archie Creek Fire is dominated by moderate and high burn severities, there was little change to the mineral soil in most instances. Soil structure was generally left intact. Roots were affected in some areas, but 100 percent root mortality was rarely observed. Water repellent soils were variable, but rarely exceeded a medium rating. However, the soils in the area are naturally disposed to erosion risk, and profound loss of vegetation and ground cover will exacerbate soil erosion.

1.2.2. WATER-REPELLENT SOIL (ACRES)

Water repellent soils are present across all SBS classes. Based on field assessments and knowledge of local soil types, some degree of water-repellence is expected to exist on all upland acres. Natural repellency is common in ash-influenced soils in the Cascades. When ground cover and organic soil layers are removed by fire, runoff related to naturally occurring repellency is commonly more pronounced or more efficient. In some locations it is likely longer fire residence time has exacerbated inherent water repellency by increasing areal extent and repellency class, however it is not possible to make reliable predictions without extensive, intensive data collection.

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1.2.3. SOIL EROSION INDEX

The soil erosion index (SEI) describes the sensitivity for soil loss after disturbance removes the protective vegetation and litter cover. The SEI is primarily a function of hillslope soil processes and hydrologic function, as influenced by disturbance, such as fire, and slope. The SEI is described as “low”, “moderate”, “high” or “very high”. Low SEI indicates soil erosion is unlikely. Moderate SEI indicates soil erosion is likely with a potential decrease in soil productivity. High SEI indicates soil erosion is very likely to decrease in soil productivity. Very high SEI indicates a high probability for soil loss and decreased soil productivity, where erosion control measures are impractical and cost prohibitive.

Figure 3. Soil Burn Severity – Archie Creek Fire

Figure 4. displays the spatial distribution and acres by SEI for the area burned by Archie Creek Fire.

The matrix values in the map table represent combinations of inherent SEI with SBS. The analysis estimates 76% of the burned area has increased potential for accelerated soil erosion. The very high SEI is generally attributed to over-steepened slopes where SBS has minor influence to change soil erosion.

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Figure 4. Soil Erosion Index – Archie Creek Fire

1.2.4. EROSION POTENTIAL

This analysis identifies hillslopes where post-fire accelerated erosion elevates the level of threat to downslope critical values. Estimates for hillslope soil loss were generated using the Water Erosion Prediction Project Cloud -Disturbed (WEPPCloud - Disturbed) Model (Robichaud and others 2019). A total of 8 drainages across 4 subwatersheds (HUC12) were evaluated. Each drainage was modeled for post-fire response using the SBS data and compared to unburned conditions. The estimated increase in soil loss per watershed unit area ranges from 0.1 to no change up to 4 tons/acre the first year after the fire, averaging about 2 tons/acre increase across the burned watersheds of interest. On average there is roughly an estimated 10-times increase in potential soil erosion post-fire over undisturbed conditions. The magnitude of increase for post-fire erosion was largest across the Rock Creek tributary near the Rock Creek Fish Hatchery, Harrington Creek, Kelly Creek and McComas Creek. with Hinkle, Beaty and Honey Creek have smaller predicted increases.

1.2.5. ESTIMATED VEGETATIVE RECOVERY PERIOD (YEARS)

This is the estimated period of time (years) for the burned area to develop vegetation sufficient to reduce runoff and erosion potential to essentially pre-fire conditions. Vegetation recovery varies

DR-4562-OR – December 2020 11 depending on plant association group, soil type, aspect, and soil burn severity. Areas burned at low severity will generally recover within two years. Areas impacted by moderate SBS may recover the understory and shrub layers in 3-5 years. For areas having high SBS and stand-replacement fire with loss of overhead canopy from conifer tree species, ecosystem recovery will take up to 2-3 decades.

Figure 5. Watershed Response in Runoff Magnitude Increase – Archie Creek Fire

1.2.6. ESTIMATED HYDROLOGIC RESPONSE

Regional regression equations were used to estimate pre- and post-fire peak flows. The relative increase in 5-year post-fire peak flows is expected to be largest in Lone Rock Road, Rock Creek and Honey Creek basins. These drainages are predicted to be roughly 1.4 to 1.6 times greater than the pre-fire peak flow magnitude at the 5-year recurrence interval. The elevated peak flow response is due to greater percentage of area having moderate or high SBS. In contrast, the estimated increase in magnitude for post-fire peak flows in the other basins is 1.1 times the pre-fire peak flow (Figure 5). The 2020 ETART Archie Creek Hydrology Report provides the detailed analysis for post-fire hydrologic response.

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These basins were created to estimate watershed characteristics, estimate post-fire response for runoff and assess the need for treatment actions. This analysis of relative stream response should only be used as a tool to better understand varying levels of risk presented by post-fire peak flows in context of downstream values. Post-fire stream response in smaller watersheds tends to be much greater than those in large watersheds. This is because of the relative volume of water it takes to show an amplified increase from pre-fire flow and the spatial scale of continuous high-severity fire patches in relation to the extent of a storm event in the Cascades.

2. Risk Assessment and Recommendations The ETART resource groups identified numerous values having varying degrees and types of threats, which are listed in the ETART Archie Creek Fire Values Table. The post-fire watershed conditions determined through field assessment and data analysis were used by the ETART to validate post-fire threats and, subsequently, using the risk assessment matrix assign each specific value a level of “Risk” defined by the probability of damage or loss coupled with the magnitude of consequences (Figure 6). A burned area emergency exists when a value has a risk rating of “very high” or “high” for all values and an “intermediate” risk for life and safety. These values are prioritized for emergency response or stabilization actions known to mitigate potential threats or minimize expected damage.

Probability of Damage or Loss

Magnitude of Consequences

Major Moderate Minor

Very Likely Very High Risk Very High Risk Low Risk

Likely Very High Risk High Risk Low Risk

Possible High Risk Intermediate Risk Low Risk

Unlikely Intermediate Risk Low Risk Very Low Risk

Figure 6. Risk Matrix

2.1. Human Life and Safety Summary

2.1.1. HAZARD TREES

Very High risk to motorists along roadways, people near structures, and visitors and employees at recreation areas from falling of hazardous trees killed or damaged by fire. These locations have large numbers of dead and fire damaged trees (>75% basal area (BA) mortality). There is “Very High” risk (likely, major) in areas having 1-75% BA mortality, as well. Although there are generally lower numbers of dead and fire damaged trees, the threat will result in major consequences to human life and safety (and property). An estimated 340 road miles have moderate to high levels of basal area mortality, where fire-killed or damaged trees are within falling distance to reach a road

DR-4562-OR – December 2020 13 on state and private lands. There are over 263 acres of hazard trees within the 100’ buffer surrounding all structures. There are 180 structures in areas that suffered 50% or greater basal area mortality. Another 76 structures are in areas that suffered less than 50% basal area mortality.

Specific areas of concern noted by the ETART include all the Rock Creek Fish Hatchery and the Rock-ed Outdoor Education Center.

Recommendation: Temporary road and sites closures until hazard trees are mitigated, minimize exposure to buildings, fell danger trees within striking distance of roadways and structures. Post hazard warning signs. Inform county emergency management, stakeholders and private landowners. Complete site-specific assessments for specific treatment recommendations.

Available resources for on-the-ground assessment of danger/hazard trees

OSU Fire Extension has recorded several post-fire webinars. Link to webinars and an extensive summary of available resources: https://extension.oregonstate.edu/fire-program.

ODF post-fire resources, including information on locating stewardship foresters:

(https://www.oregon.gov/odf/fire/Pages/afterafire.aspx).

Field Guide for Danger Tree Identification and Response along Forest Roads and Work Sites in Oregon and Washington:

http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd512960.pdf).

Post-fire tree mortality assessment and marking guidelines:

https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd814664.pdf).

To arrange for on-the-ground training contact ODF or OSU Extension Services. USFS State and Private Forestry also has experts on staff to help with post-fire trainings at the request of ODF.

2.1.2. DEBRIS FLOW, ROCK FALL, AND LANDSLIDES

Very High risk to life and safety Rock Creek Fish Hatchery and at Rock-ed Outdoor Education Center from debris flows and landslides. Facilities and structures located on values located in floodplains, debris flow paths or depositional zones. Steep slopes directly adjacent to hatchery; and outdoor education center property and the hatchery is located on toe of active landslide and within in deposition zone of debris flows.

https://extension.oregonstate.edu/fire-program https://extension.oregonstate.edu/fire-program https://www.oregon.gov/odf/fire/Pages/afterafire.aspx http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd512960.pdf https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd814664.pdf

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Recommendation: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations. Information sharing with County Emergency Management, communities, and property owners on needs for further evaluation or assessment. Facility closures, education, install hazard warning signs, use weather alert systems or monitoring.

High risk to life and safety at Annabell Road and Kelly Creek (private homes), Evergreen Lane and Dogwood Hotel, Hogback Creek, Honey Creek, Moore Hill Lane, OR138, Rock Creek Road, Susan Creek Campground, and Idywild Park from debris flows, rock fall or landslides. Properties and communities are located in floodplains, at the mouth of channels, and within debris flow deposition zones.

Recommendation: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations. Information sharing with County Emergency Management, Low risk to life and safety at Richard Baker Memorial Park, Smith Springs County Park, the Narrows Day Use Area, and Nonpareil Road from debris flows, rock fall or landslides.

Recommendation: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations.

2.1.3. POST-FIRE FLOODING, FLOATING DEBRIS, AND OTHERS

Intermediate risk to visitors and employees at Rock Creek Fish Hatchery and at Rock-ed Outdoor Education Center from logs, debris and sediment flow into fish hatchery. High mortality of trees upstream, steeps slopes with debris flow hazard.

Recommendations: Close facilities, clean debris and logs as needed and consider berms/debris diversion structures. Inform county Emergency Management, use hazard warning signs and early warning system/weather alerts.

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2.2. Property Summary

Very High risk to property at Rock Creek Fish Hatchery and at Rock-ed Outdoor Education Center from debris flows and landslides, as well as logs, debris and sediment flow into hatchery. Facilities and structures located on values located in floodplains, debris flow paths or depositional zones.

Steep slopes directly adjacent to hatchery; and outdoor education center property and the hatchery is located on toe of active landslide and within in deposition zone of debris flows. There is a high mortality of trees mortality upstream, steep slopes with debris flow hazard increases potential for damage, but unlikely to be total loss. A potential threat is clogging of water intakes from increased loading of sediment and large wood (e.g., Rock Creek Fish Hatchery).

Recommendation: For protection of water intakes, increase frequency of inspection and debris removal, and outreach to the private landowners with water intake systems to increase awareness of the potential threats and recommended mitigations. Clean debris and logs as needed; consider berms/debris diversion structures.

Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations for geologic hazards. Information sharing with County Emergency Management, High risk to properties at Annabell Road and Kelly Creek, Evergreen Lane and Dogwood Hotel, Hogback Creek, Honey Creek, Moore Hill Lane, OR138, Rock Creek Road, Susan Creek Campground, and Idywild Park from debris flows, rock fall or landslides. Properties and communities are located in floodplains, at the mouth of channels, and within debris flow deposition zones.

Recommendation: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations. Information sharing with County Emergency Management, Resources for private landowners

The Natural Resources Conservation Service (NRCS) provides information about actions that can be take on your private property. Please see this list of fact sheets (click here) for details different treatment options that can be taken to combat erosion risks.

https://www.nrcs.usda.gov/wps/portal/nrcs/detail/or/programs/financial/eqip/?cid=stelprdb1261654#:%7E:text=Post%2Dfire%20Soil%20Conservation%20Measures,bales%20and%20wattles%2C%20mulching

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High risk to private home and access road at mouth of Honey Creek from debris and hillslope slump blocking and redirecting flow into floodplain. Narrow channel with adjacent steep slopes and no understory increases potential for channel diversion and overbank flows, depositing sediment on property and impacting water quality.

Recommendation: Property acquisition. Inform stakeholders of risks and advise on threat mitigation recommendations (e.g. engineering teams to inspect culverts and other road infrastructure) and storm alert systems. For hillslope stabilization there are multiple proven treatments effective against low degrees of hillslope erosion: mulching, slash spreading, erosion barriers, wattles, silt fences, debris deflectors, and protective fences.

High risk to privately-owned land near Honey Creek from hillslope erosion and sediment bulked flows depositing sediment onto private property/burned homesite. Property is located at the bottom of a confined drainage within the floodplain. There are no structures on the property, but deposited sediment may impede access and use of the site.

Recommendation: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations. Inform stakeholders of risks and advise on threat mitigation recommendations (e.g. engineering teams to inspect culverts and other road infrastructure) and storm alert systems. For hillslope stabilization there are multiple proven treatments effective against low degrees of hillslope erosion: mulching, slash spreading, erosion barriers, wattles, silt fences, debris deflectors, and protective fences.

High risk to private residences along Evergreen Loop Road and Evergreen Road from debris, sediment and clogged culverts. Hazard trees with debris in road ditches and culvert inlet basins increasing threat for water diversion to plug culverts and damage road surface.

Recommendations: Hazard tree removal and road maintenance. Inform stakeholders of risks and advise on threat mitigation recommendations (e.g. engineering teams to inspect culverts and other road infrastructure) and storm alert systems. For hillslope stabilization there are multiple proven treatments effective against low degrees of hillslope erosion: mulching, slash spreading, erosion barriers, wattles, silt fences, debris deflectors, and protective fences.

High risk to Winchester Dam from woody debris and sediment deposition. Structure is designed to have flow overtop the dam. Steep slopes having high mortality of trees upstream increase potential for mobilized debris; debris will stack up against the dam but should flow over during high water.

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Recommendations: Update the Emergency Action Plan to account for woody debris. Remove any logs that threaten the water intake structure or the fish ladder at the ends of the dam.

Intermediate risk to Quarry on BLM Road 25-2-11 (private property/infrastructure) because of high probability for debris flow.

Low risk to property at Richard Baker Memorial Park, Smith Springs County Park, the Narrows Day Use Area, Nonpareil Road, and power transmission lines (south side of the fire and along OR193) from debris flows, rock fall or landslides.

Low risk was found for Douglas County and private roads from debris flow and plugging potential causing culvert failure. The roads at risk within the Archie Creek Fire burned areas are located primarily within or below areas of high and moderate SBS. There is a future threat to travelers along the roads within the burned area due to the increased potential for culverts plugging with sediment or debris which could washout sections of the roads. With the loss of vegetation, normal storm frequencies and magnitudes can more easily initiate erosion on the slopes, and it is likely that this runoff will cover the roads or cause washouts at drainage facilities (culverts) or stream crossings.

These events make for hazardous access to forest roads and put the safety of users at risk. These roads will require minimal action to maintain open and safe to all traffic. See Appendix A for Road Treatment Cost Estimates.

Recommendations: Storm proofing and Storm Inspection and Response

Bar-L Ranch Road (County). Hillslope and road ditch debris diverting runoff and crossing failures from burned culverts increase potential for road damage. One culvert was burned in fire resulting in collapsed road surface (isolated occurrence). Replace burned culvert.

Evergreen Loop Road (County) for road surface damage. Hillslope and road ditch debris diverting runoff and debris in culvert basin increase potential for road damage. Evidence of pre-existing culvert plugging which will likely be exacerbated by increased runoff from burned drainages (isolated occurrences).

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Recommendations: Coordination with landowner on storm patrol and hillslope stabilization

Beaty Creek crossing at Road 24-3-33.7 (Federal/Private Industrial). Debris and sediment in culvert basin plugging culvert and impacting surrounding road fill. Small drainage area with gravelly soils and low SBS above crossing. Road primarily accesses private and BLM timberlands.

Hinkle Creek crossing at Road 24-3-31.1 (Federal/Private Industrial). Debris and sediment in culvert basin plugging culvert and impacting surrounding road fill. Small drainage area with gravelly soils and low SBS above crossing. Road primarily accesses private and BLM timberlands.

Rock Creek Bridge (Federal/Private Industrial). Large log was anchored under bridge footing, which burned up, resulting in a gap and possible erosion under bridge footing under elevated flows. The stream is large with a wide floodplain, but increased debris and sediment may rise water levels to area of gap in bridge footing. Destabilized bridge footing would require costly repairs; road is a main access route through Rock Creek.

Harrington Creek Bridge (Federal/Private Industrial). Debris and sediment deposition upstream of bridge possibly damaging bridge footings. Very narrow channel and crossing with moderate SBS and abundant hillslope and channel debris above bridge. Mobilized debris may damage bridge resulting in loss of use; bridge provides access to private industrial and BLM lands.

Kelly Creek Culvert (Federal/Private Industrial). Debris and sediment deposition upstream of culvert increases potential for damage to or loss of road crossing. Large diameter culvert has restricted in-flow and moderate SBS above stream channel with large amount of standing dead wood. Armored culvert inlet basin, deep fill and paved road would result in substantial cost to repair damage.

Low risk to private residences along Bar L Ranch Road and Lone Rock Road from debris, sediment and burned culvert. Potential for hillslope and road ditch debris to divert runoff and cause failure of burned culvert, increasing threat for water diversion to damage road surface. Risk for property damage from falling trees.

Recommendations: Hazard tree removal and replace culvert on Bar L Ranch Road.

Low risk to private homes along N. Umpqua River on Smith Springs Drive from increased bank erosion. Existing eddy known to collect debris and logs; expected increase in mobilized debris with potential for bank erosion and nuisance flooding.

Recommendations: Education and outreach with property owners.

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Road Treatments

Storm Proofing. Clean/pull ditches, clean stream crossing culvert inlets/outlets and relief culverts, run out ditches and catchment basins of sediment, debris and rock. Out slope the road prism where appropriate. Replace or repair damaged culverts pending the need of primary maintainers. Slotted riser pipes or culvert end sections could be installed where feasible and appropriate to reduce the potential for sediment and debris plugging of existing culverts.

Storm Inspection and Response. Follow-up to storm proofing to monitor functionality post-storm event. Monitor road conditions after a storm for the first year, deploying personnel to inspect and react as appropriate. Re-storm proof may be needed after a damaging storm to keep ditches, culverts and critical dips in working order.

Storm Patrols. Monitor road drainage structures and debris flow treatment structures after significant storm events to ensure the maximum drainage capacity is maintained until the natural revegetation of the burned area has occurred. Maintain and/or repair any damage to road surfaces. Remove sediment and debris from drainage and treatment structures and stabilize head cutting in streams and drainages to prevent further degradation of channels. Monitor the movement of large woody debris, make a determination to remove material before it contacts bridge piers, abutments or culverts.

If feasible and cost effective, replace culverts to handle the post fire flows. Culverts being replaced should be sized on predicted increase in flows and installed with minimum fill cover and heavy armoring. If culvert is not replaced, proceed with monitoring and ditch cleaning along the roads identified in the Archie Creek Fire Engineering Report.

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2.3. Natural Resources Summary

2.3.1. SOIL AND WATER

High risk to soil productivity from accelerated erosion. High and moderate SBS on steep slopes increase potential for loss of topsoil. Ground cover in clear-cut areas may take longer than 2-5 years to establish and decrease longer term erosion.

Recommendations: Further evaluation is needed to define site-specific threats to values and identify appropriate mitigations. Apply mulch, preferably by chipping existing dead vegetation.

Re-establish vegetation cover.

2.3.2. FISH AND WILDLIFE HABITAT

Very High risk to T&E fisheries habitat from water quality impairments (temperature). Loss of riparian shading leading to increased stream temperatures. A number of stream reaches experienced complete or partial loss of trees in riparian areas. This will result in increased solar radiation entering streams until vegetation regenerates. Temperature increases are likely to last multiple years (potentially 10+ years in high burn severity areas) thereby impacting several generations. In a number of locations, stream temperatures during summer were already close to the thermal tolerance limits for fish species. The actual magnitude will depend on future climatic conditions and pace of regeneration.

Recommendations: Work with partners to encourage natural regeneration and/or reforestation with mixed hardwood conifer.

High risk to water quality that supports T&E habitat in Rock Creek basin from contaminants from burned debris. Runoff from developed lands containing hazardous wastes poses risk to aquatic species. A number of urban areas were subject to fire damage and are in proximity to waterways.

Efforts to remove hazardous wastes are underway but in some instances surface runoff from rains has already occurred or will occur before wastes are removed. Environmentally persistent contaminants introduced to waterways may have multigenerational impacts. Other more transient chemicals will likely impact one to two generations within the area of exposure.

Recommendations: Work with partners to identify and prioritize hazardous waste removal in proximity to waterways.

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High risk for decreased productivity at Rock Creek Hatchery from debris and/or sediment impinging on water intake screens during high flows. A large amount of the Rock Creek watershed experienced high SBS and vegetation mortality. There is increased potential for delivery of sediment, ash and debris to the river this winter. High volumes of sediment and debris that damage intake systems or impact water quality are likely to have considerable impact on future ability to rear fish on site.

Recommendations: Implement increased monitoring and frequent screen regiment.

Low risk to T&E fisheries habitat from water quality impairments (turbidity). Runoff of ash and sediment represents a near-term threat to spawning success for salmonids and lamprey. A large portion of several watersheds containing spawning habitat for salmon, trout and lamprey was burned leaving significant ash deposits. Control measures will not be sufficient to prevent this from entering waterways during rain events. Some areas may experience increased redd failure, but likely there is sufficient alternate spawning habitat to sustain populations.

No treatment recommended.

Low risk to T&E fisheries spawning, rearing and refugia habitat access for ESA-listed species.

Increased runoff resulting from lack of vegetative cover may result in higher peak flows leading to increased scour of redds and/or displacement of some species. A number of watersheds experienced high levels of vegetative mortality at mid- to low elevations. Winter forecasts suggest a likelihood of wetter weather. This combination of conditions creates higher likelihood of significant rainstorm/runoff events with impacts are likely to be transient (affect 1-2 generations) and spatially heterogenous.

No treatment recommended.

Low risk for impacts to migration habitats or loss access to rearing and spawning habitats from damage to Rock Creek Fish Ladder. Rock Creek watershed experienced a large percentage of high SBS and vegetation mortality. There is increased potential for debris to be mobilized and delivered to the river this winter (and in subsequent winters). Debris blocking or damaging the fish ladder will impact the ability of fish to move upstream

Recommendations: Implement increased monitoring and frequent ladder cleaning regiment to remove debris blocking fish passage.

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Low risk to T&E fisheries spawning, rearing and refugia habitat access for ESA-listed species.

Increased runoff resulting from lack of vegetative cover may result in higher peak flows leading to increased scour of redds and/or displacement of some species. A number of watersheds experienced high levels of vegetative mortality at mid- to low elevations. Winter forecasts suggest a likelihood of wetter weather. This combination of conditions creates higher likelihood of significant rainstorm/runoff events with impacts are likely to be transient (affect 1-2 generations) and spatially heterogenous.

No treatment recommended.

General Fish and Wildlife Recommendations Early Seral Habitat - Seneca Jones Timberlands. Assist landowners with reseeding to benefit deer and elk, provide soil stability and minimize expansion of invasive plants in areas of moderate to high SBS. Timberlands experienced high vegetation mortality (76-100% BA) over a large area.

Reseeding and stabilizing roadbeds is known to have major benefits to maintain early successional species as well as reduce erosion and decrease susceptibility for invasive plants to occupy disturbed areas.

Maintain or Restore Aquatic Habitat Connectivity. Work with partners to identify priorities and options for fish passage at stream crossings; implement aquatic organism passage options when upsizing or replacing burned/washed out culverts. Given scale of fires and the number of culverts on the landscape, it is likely some culverts were or will be impacted. Restoring passage allows fish to access suitable habitat or refugia if primary habitats are impacted by post-fire events.

Riparian Shade - Rock Creek Basin, lower reaches of Honey Creek, Susan Creek, Cougar Creek, Williams Creek, Wright Creek and Fall Creek. Work with partners to identify artificial revegetation and/or natural regeneration practices that rapidly restore riparian shading. Locations are variable depending on burn severity and extent of active management. Many streams within the burn areas have summer temperatures close to thermal tolerance limits. Allowing a mix of hardwood/conifer in riparian areas promotes more rapid recovery of intermediate shading from hardwoods may be key to ensuring these streams remain suitable during summer in the near term.

Large Woody Debris (LWD) - Rock Creek Basin, Hinkle Creek Basin, lower reaches of Canton Creek, South Fork Calapooya Creek and Engels Creek. Work with partners to encourage alternative salvage harvest practices that retain LWD, to the extent practicable, for recruitment into stream channels.

Locations are variable depending on extent of post-fire salvage harvest occurring within riparian zones. Many of the rivers and streams have historically low levels of LWD. Maintain standing or dead trees within riparian areas could potentially reset the system and provide substantial long-term benefits in terms of creating suitable habitat for aquatic and terrestrial species. As these trees enter streams and rivers, they create high quality habitat for salmonids.

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Keystone species. Work with partners to identify alternative artificial revegetation and/or natural regeneration practices for long-term beaver habitat. Locations are variable depending on management goals. Promoting hardwood regeneration in riparian areas provides conditions for beaver to construct dams that benefit a range of aquatic species. Beaver are ecosystem engineers that create habitats for many aquatic species, including salmonids. To build dams, beavers require suitable plant materials (typically willow, alder, etc.).

Refugia (Intact Ecosites/Ecosystems). Work with partners to encourage natural regeneration and minimize disturbance to the extent practicable to protect intact landscapes with low burn severity, low vegetation mortality and low road/trail disturbance. These areas are important refugia and source areas for species displaced by the fire, particularly late seral obligates. Given large areas of habitat burned at moderate to high SBS, maintaining high quality core habitat is critical to retaining source populations of some species, as loss of late successional forest will have long-term effect on species such as the Northern spotted owl.

Standing Dead Wood. Work with partners and landowners to encourage natural regeneration and limit salvage harvest, to the extent practicable, to retain burned wood on the landscape. Large areas with moderate to high SBS and high vegetation mortality result in a high density of snags and woody debris that are used by a variety of terrestrial species. Use of severely burned forest by late successional species such as Northern spotted owl will depend on patch size and availability of unburned or lightly burned habitat nearby.

Early-successional Ecosystems. Work with partners to prioritize revegetation and reseeding for native plant species to promote habitats for pollinators, high-value forage and minimize expansion of invasive plant species. Appropriate post-fire management of forest and meadow early seral habitats ensures desirable successional pathways that are critical to recovery of early seral plant species, particularly in moderate to high SBS areas.