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Hydrology Resource Report CANYON CREEK/BOULDER CREEK LAKES TRAIL REROUTE PROJECT USDA FOREST SERVICE, TRINITY RIVER MANAGEMENT UNIT SHASTA-TRINITY NATIONAL FOREST, REGION 5

Prepared by: 08/16/2012 [Stephen Bachmann]

Hydrologist Date

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Canyon Creek/Boulder Creek Lakes Trail Re-route Project Hydrology Resource Report - 08-16-2012

2 - Shasta-Trinity National Forest, Trinity River Management Unit

Report Summary: This report evaluates the effects of proposed activities on water quality and aquatic and riparian environments associated with the proposed action on the Canyon Creek and Boulder Creek Lakes Trails. The proposed action and alternatives are described in the context of the Canyon Creek Watershed hydrologic setting. The environmental consequences of the proposed action and alternatives as they pertain to water resources are described within the context of direct, indirect, cumulative effects and the Aquatic Conservation Strategy. Water resource protection measures are identified for project activities. This analysis finds that with proper adherence to the design criteria that the proposed action will improve water quality and aquatic/riparian habitats and will not result in adverse effects to water resources in the Canyon Creek Watershed.

1. Regulatory Framework

1a. Forest Plan Direction for Water Resources Management The Shasta-Trinity National Forest Land and Resource Management Plan (LRMP) directs management of water resources on the Shasta-Trinity National Forest.1 Plan direction for water resources is provided in the context of Forest Goals, Standards and Guidelines, and more specific Management Area direction, as well as the Aquatic Conservation Strategy (ACS)2, Watershed Analysis3 and guidelines for Riparian Reserve Management.4 These topics are discussed where applicable in this report.

Guidelines for Water Resource Management are described in Chapter 4 – Management Prescriptions under Riparian Reserves and Key Watersheds.5 All of the guidelines in the Shasta-Trinity National Forest Land and Resource Management Plan are based on the Standards and Guidelines from the Record of Decision (ROD) for Amendments to Forest Service and Bureau of Land Management Planning Documents within the Range of the Northern Spotted Owl.6 The 1994-ROD was amended in 2004 in order to clarify provisions related to the Aquatic Conservation Strategy.7 The 2004-ROD automatically amended the Shasta-Trinity Land and Resource Management Plan. In May 2007 further direction on how to implement the Aquatic Conservation Strategy was provided in a memo entitled “Compliance with the Aquatic Conservation Strategy.”8 This direction specifies that each project must be analyzed at the project level for potential effects on the nine ACS objectives.

1 USDA Forest Service, 1995. Land and Resource Management Plan, Shasta-Trinity National Forests. (LRMP) 2 LRMP, p. 4-53. 3 LRMP, p. 4-53. 4 LRMP, p. 4-53 – 4-60. 5 LRMP, p. 4-53 – 4-60. 6 USDA Forest Service and USDI Bureau of Land Management, 1994. Record of Decision for Amendments to Forest Service and Bureau of Land Management Planning Documents within the Range of the Northern Spotted Owl, including Standards and Guidelines for Management of Habitat for Late-Successional and Old-Growth Related Species. 7 USDA-FS; USDI-BLM, Record of Decision Amending Resource Management Plans for Seven Bureau of Land Management Districts and Land and Resource Management Plans for Nineteen National Forests Within the Range of the Northern Spotted Owl (USDA Forest Service and USDI Bureau of Land Management, March 2004). 8 USDA Forest Service, USDI Bureau of Land Management, 2007. Memorandum - Compliance with the Aquatic Conservation Strategy. 3 p.

Canyon Creek/Boulder Creek Lakes Trail Re-Route Project, Hydrology Report, August 16, 2012

Shasta-Trinity National Forest – Trinity River Management Unit - 3

Applicable Forest Goals Water

• Maintain or improve water quality and quantity to meet fish habitat requirements and domestic use needs (LRMP 4-6).

• Maintain water quality to meet or exceed applicable standards and regulations (LRMP 4-6). Riparian Areas

• Maintain or improve riparian habitat (LRMP 4-5).

Applicable Standards and Guidelines Riparian Areas

• The Riparian Reserve Standards and Guidelines, found in the Management Prescription section under Riparian Reserves, apply to all 2.1 million acres of the Shasta-Trinity National Forest (LRMP 4-24).

• Maintain riparian area values, particularly when locating and constructing new roads and trails

(LRMP 4-25). • Identify and treat riparian areas that are in a degraded condition (LRMP 4-25).

Water

• Implement Best Management Practices for protection or improvement of water quality, as described in “Water Quality Management for National Forest System Lands in California,” for applicable management activities. Determine specific practices or techniques during project level planning using information obtained from on-site soil, water, and geology investigations (LRMP 4-25).

• Identify and treat areas with a degraded watershed condition in a cost-effective manner and

according to beneficial use priorities. High priority items include domestic use, anadromous fish habitat, and sensitive species habitat. Improvement activities will be designed to meet Management Area objectives (LRMP 4-25).

• Give full recognition to the tendency for erosion, mass land movement, and severe watershed

damage potential when implementing vegetation management and related land management activities (LRMP 4-25).



1b. State and Federal Direction for Water Resources Management – Best Management Practices

Management direction comes from the Shasta-Trinity National Forest Land and Resource Management Plan (LRMP) as well as State of California Water Quality Control Board, both of which have best management practices to guide implementation of activities to be in compliance with the Clean Water Act. The State of California has agreements with the U.S. Forest Service to control non-point source discharges by implementing control actions certified by the state Water Board as Best Management Practices (BMPs).

Best Management Practices are designed to protect the beneficial uses of water and will be implemented for each management practice. Because of these measures, no irreversible or irretrievable impacts to water quality are expected to occur, thus meeting Clean Water Act requirements. The proposed action complies with the Clean Water Act by following the best Management Practices outlined in the management agency agreement with the State of California.9

2. Description of Proposed Action Project Summary: The Trinity River Management Unit of the Shasta-Trinity National Forest is proposing to reroute 2 segments of trail to reduce impacts to riparian and aquatic habitats and provide improved access for recreation users (see Map 1 for segment locations at end of document). The purpose and need for the projects is to design, construct, and maintain the Canyon Creek and Boulder Creek Lakes trails to withstand the normal traffic and reasonable user behavior during the managed season of use in order to have minimal negative effects on adjacent resources. Trail Segment 1 - Canyon Creek Trail: The proposal is to reroute approximately 2,000 feet of the Canyon Creek trail from an area that receives high amounts of sheet flow during the annual snow melt season (see photo 1). This section of trail currently crosses approximately five small seasonal streams just below their points of origin. This section of trail has captured the flow of the five streams and channelized causing erosion. Users now detour around this section of trail during wet conditions, causing the trail to widen every season. The proposed reroute will travel above the springs that are the starting points for much of the water that is currently impacting the trail system. This reroute will move the trail from a relatively flat section that provides little opportunity for water removal to a drier site that has sufficient side slope to allow water to cross the trail rather than flow down it. The reroute has been laid out and designed with frequent grade reversals in an effort to minimize the capture of sheet flows of water.

Trail Segment 2 – Boulder Creek Lakes Trail: The proposed action is to reroute approximately 800 feet of the Boulder Creek Lakes trail from a wet meadow onto more appropriate ground. This section of trail crosses a relatively flat meadow; little opportunity to remove water from this section of trail exists. This boggy section of trail has several scars as users have detoured round the ankle deep muck over the years in an effort to stay dry and avoid the muddy conditions. The proposed reroute will move the trail out of the sensitive meadow and onto ground with suitable slope and soils to allow cross drainage and provide a more pleasant route for the trail users. This project will eliminate a high impact section of multiple routes with a single route that is less impactful to the resource.

9 USDA Forest Service, Pacific Southwest Region, Sept. 2000. Water Quality Management for Forest System Lands in California, Best Management Practices.



Both trail segments will also include rehabilitation and naturalization of the existing trail tread. This includes constructing check bars/dams and placing vegetation, large woody debris and rocks removed from the new trail segments onto the old trail. Construction and rehabilitation work will take approximately two months to complete, and will begin in spring 2013.10

All trail work for both segments would be accomplished with non-motorized and non-mechanical equipment. The new trail segments will be constructed to standards described in Forest Service handbook 2309.18 - Trail Management Handbook.11 The following design parameters will be used for all new trail segments.

• Design Tread Width: The trail will generally be 24-inches wide; however it may be up to 48-inches wide along steep side slopes and 48-60-inches wide along precipices.12

• Design Surface: Native, with improved sections of borrow or imported material and routine

grading, minor roughness.

• Design Grade: Target grade is 2-10%, short pitches may have a maximum grade of 15%.

• Design Cross Slope: Target cross slope is 0-5% with a maximum of 5%.

• Design Clearing: Height is 10-12 feet; width is 96-inches. Shoulder clearance is 12-18 inches and pack clearance is 36x36 inches.

3. Affected Environment Location and Geographic Boundary: The Canyon Creek and Boulder Creek Lakes Trails are located in the Trinity Alps Wilderness in northwestern Trinity County, California, on the Trinity River Management Unit of the Shasta-Trinity National Forest. Both trails are within the Canyon Creek Watershed. Canyon Creek drains a watershed area of 40,890 acres and is a tributary to the Trinity River. The Canyon Creek Watershed is one of the most popular and heavily traveled destination areas in the Trinity Alps Wilderness. Thirty-two percent of the total user days for the entire Wilderness Area are recorded in the main arm of the Canyon Creek Watershed.13 Climate: The Canyon Creek Watershed has a Mediterranean climate characterized by hot, dry summers and cold, wet winters. Snow frequently accumulates above 4,000 feet elevation during the winter months. Elevations between 3,000 feet to 4,000 feet are frequently subjected to rain on snow events. Mean annual precipitation varies between 70 inches in the upper portions of the watershed to nearly 40 inches at the lower end. About 90 percent of the precipitation falls between October and April, with snow usually remaining at higher elevations through May or June.14 Land Management Allocations: The Canyon Creek Watershed has been designated as a Tier 1 Key Watershed in the Shasta-Trinity Land and resource Management Plan (LRMP). Tier 1 Key Watersheds 10 USDA Forest Service, 2012. Draft Recreation Resource Wilderness Report for Canyon Creek Boulder Creek Trail Reroute Project. 11 USDA Forest Service, 2008. FSM 2309.18 – Trails Management Handbook. 12 USDA Forest Service, 2008, FSM 2309.18 – Trails Management Handbook, Chapter 20, Section 23.12. 13 USDA Forest Service, 2003. North Fork Trinity River, East Fork North Fork Trinity River and Canyon Creek Watershed Analysis. 14 USDA Forest Service, 2003. North Fork Trinity River, East Fork North Fork Trinity River and Canyon Creek Watershed Analysis.



contribute directly to conservation of at-risk anadromous salmonids, bull trout, and resident fish species.15 Canyon Creek has also been identified as Critical Habitat for SONCC16 coho salmon. Both trail segments occur within the Wilderness and Riparian Reserve land allocations. The majority of the Canyon Creek trail is located within Riparian Reserves. Riparian Reserves are managed to maintain or enhance riparian area, wildlife and fisheries habitat, and water quality by emphasizing streamside and wetland management.17

Photo 1: Existing section of Canyon Creek Trail showing concentrated surface flow on trail prism (2012).

4. Environmental Consequences The environmental consequences of the proposed action and alternatives are discussed within the context of direct effects, indirect effects and cumulative watershed effects for each alternative. Effects are also discussed within the context of the Aquatic Conservation Strategy Objectives.

4a. Direct and Indirect Effects

a) Direct Effects to Water Quality and Riparian/Aquatic Habitats Proposed Action

• Ground disturbance would occur as a result of clearing vegetation on new trail alignments and would be restricted to the width of the prism. Small amounts of vegetation would be removed from Riparian Reserves at one intermittent stream crossing on the realigned segment of the Canyon Creek Trail. The remainder of vegetation removed will be associated with the Riparian Reserve buffer outside of actual riparian and aquatic habitats.

15 LRMP, 4-58. 16 Southern Oregon/Northern California Coast. 17 LRMP, 4-59.



• For the lower realignment on Canyon Creek: Creation of a new trail alignment that crosses one intermittent stream course and decommissioning of a trail segment that currently crosses 5 intermittent stream courses.

• Small amounts of ground disturbance would occur on rehabilitated trail segments. Ground disturbance would be associated with the construction of small check dams designed to dissipate trail surface flow and restore the trail prism.

No Action

• No direct effects would occur from the proposed action. • Continued impacts to water quality, and aquatic/riparian habitats from hikers and stock use on

wet trail segments.

b) Indirect Effects to Water Quality and Riparian/Aquatic Habitats Proposed Action

• Gradual vegetative recovery of rehabilitated trail segments due to placement of check dams/bars and increased roughness from spreading rock and vegetation from new trail segment on rehabilitated trail prism. Vegetative recovery is expected to commence immediately upon cessation of use and should occur relatively rapidly (est. 1-5 years) in wet areas.

• Rapid improvement in water quality resulting from discontinued use of eroding trail segments and rehabilitation activities.

No Action

• No indirect effects would occur from the proposed action. • Trail condition would continue to deteriorate as hikers and stock animals continue to travel

through wet reaches. Wet meadow habitats would continue to be degraded. The impact area would likely be expanded as trail users continued to attempt to hike around wet, rutted areas further damaging adjacent areas.

• The trail prism will continue to widen over time. If allowed to continue it is possible that the channelized flow could eventually reach Canyon Creek and effectively create a new point source for the introduction of fine sediments.

• Continued trail erosion during rainfall and snowmelt events.

c) Cumulative Effects to Water Quality and Riparian/Aquatic Habitats A cumulative impact is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions. The direct and indirect effects discussed above when combined with other past, present, and reasonably forseeable actions can be cumulative in nature and have impacts to aquatic resources at varying scales. The proposed action will not cause adverse cumulative effects to water quality and riparian/aquatic habitats. While direct and indirect effects from the project exist they are too small to have an incremental effect on water resources and aquatic/riparian habitats. Furthermore the proposed action is located in the Trinity-Alps Wilderness Area in the Canyon Creek Watershed in an unroaded area with no vegetation management activities. All proposed actions are restorative in nature and will have a positive effect on aquatic and riparian habitats at the project scale by removing and rehabilitating trail segments located in sensitive areas.



4d. Effects of Proposed Management Activities on the Aquatic Conservation Strategy (Project and Watershed Scales) The Forest Plan contains the components, objectives and standards and guidelines for the Aquatic Conservation Strategy. The four components of the Aquatic Conservation Strategy are: 1) establishment and management of Riparian Reserves, 2) Key Watersheds, 3) Watershed Analysis and 4) Watershed Restoration. The action alternatives for the Canyon Creek/Boulder Creek Lakes Trail Reroute Project are consistent with recommendations in the watershed analysis associated with the assessment area and Forest Plan direction. The project is occurring in a key watershed and is designed to restore aquatic and riparian habitats in Riparian Reserves and improve local water quality by reducing trail erosion. A watershed analysis has been completed for the Canyon Creek Watershed.18 The proposed action is restorative in nature. Watershed restoration, including fish passage improvement, decommissioning, and storm damage repair, is an ongoing program on the Forest. The Forest Plan also provides nine objectives that are evaluated to determine that a project or management action “meets” or “does not prevent attainment” of the Aquatic Conservation Strategy objectives.19

Objective 1. Maintain and restore the distribution, diversity, and complexity of watershed and landscape-scale features to ensure protection of the aquatic systems to which species, populations and communities are uniquely adapted.

Proposed Action: The proposed action will meet objective 1 at the project scale and not prevent the attainment of objective 1 at the watershed scale. Rehabilitation of trail segments within aquatic and riparian habitats will restore and eliminate impacts to these habitats. The realigned trail segments will avoid nearly all intermittent streams and all wet meadow habitats.

Objective 2. Maintain and restore spatial and temporal connectivity within and between watersheds. Lateral, longitudinal, and drainage network connections include floodplains, wetlands, upslope areas, headwater tributaries, and intact refugia. These network connections must provide chemically and physically unobstructed routes to areas critical for fulfilling life history requirements of aquatic and riparian-dependent species.

Proposed Action: The proposed action will meet objective 2 at the project scale and not prevent the attainment of objective 2 at the watershed scale. At the project scale, rehabilitation of trail segments that are currently channeling runoff will restore natural flow patterns and connectivity within wet meadow habitats and seasonal streams.

Objective 3. Maintain and restore the physical integrity of the aquatic system, including shorelines, banks, and bottom configurations.

Proposed Action: The proposed action will meet objective 3 at the project scale and not prevent the attainment of objective 3 at the watershed scale. The abandonment and

18 USDA Forest Service, 2003. North Fork Trinity River, East Fork North Fork Trinity River and Canyon Creek Watershed Analysis. 19 LRMP, 4-53)



rehabilitation of trail segments located within wet meadows will allow for restoration of wet meadow habitats. Relocating the trail will also eliminate and allow for the rehabilitation of four intermittent stream crossings.

Objective 4. Maintain and restore water quality necessary to support healthy riparian, aquatic, and wetland ecosystems. Water quality must remain within the range that maintains the biological, physical, and chemical integrity of the system and benefits survival, growth, reproduction, and migration of individuals composing aquatic and riparian communities.

Proposed Action: The proposed action will meet objective 4 at the project scale and not prevent the attainment of objective 4 at the watershed scale. Local water quality will be improved by abandoning and rehabilitating trail segments that are currently channeling water and eroding the trail prism in Riparian Reserves. Rehabilitation activities will increase roughness and disperse flow off the abandoned trail segments resulting in improved water quality.

Objective 5. Maintain and restore the sediment regime under which aquatic ecosystems evolved. Elements of the sediment regime include the timing, volume, rate, and character of sediment input, storage, and transport.

Proposed Action: The proposed action will meet objective 5 at the project scale and not prevent the attainment of objective 5 at the watershed scale. The trail segments proposed for abandonment and rehabilitation are actively eroding and impacting aquatic and riparian habitats. Soils are being lost from wet meadows and new user trails are being created. Rehabilitation of the abandoned trail segments will stop the erosion and allow for gradual recovery of vegetation on the former trail prisms.

Objective 6. Maintain and restore instream flows sufficient to create and sustain riparian, aquatic, and wetland habitats and to retain patterns of sediment, nutrient, and wood routing. The timing, magnitude, duration, and spatial distribution of peak, high and low flows must be protected.

Proposed Action: The proposed action will meet objective 6 at the project scale and not prevent the attainment of objective 6 at the watershed scale. At the project scale, rehabilitation of abandoned trail segments will allow surface runoff to disperse through the wet meadows, intermittent streams and other habitats instead of being channeled down the trail prism.

Objective 7. Maintain and restore the timing, variability, and duration of floodplain inundation and water table elevation in meadows and wetlands.

Proposed Action: The proposed action will meet objective 7 at the project scale and not prevent the attainment of objective 7 at the watershed scale. Rehabilitation of abandoned trail segments in wet meadows will allow for restoration of natural flow patterns and restore the timing, variability, and duration of floodplain inundation and water table elevations in meadows and wetlands.

Objective 8. Maintain and restore the species composition and structural diversity of plant communities in riparian areas and wetlands to provide adequate summer and winter thermal regulation, nutrient filtering, appropriate rates of surface erosion, bank erosion, and channel



migration and to supply amounts and distributions of coarse woody debris sufficient to sustain physical complexity and stability.

Proposed Action: The proposed action will meet objective 8 at the project scale and not prevent the attainment of objective 8 at the watershed scale. Rehabilitation of abandoned trail segments will allow for the restoration of structural diversity of plant communities in riparian areas and wet meadow habitats.

Objective 9. Maintain and restore habitat to support well-distributed populations of native plant, invertebrate and vertebrate riparian-dependent species.

Proposed Action: The proposed action will meet objective 9 at the project scale and not prevent the attainment of objective 9 at the watershed scale. Rehabilitation of abandoned trail segments will restore riparian and wet meadow habitats and improve overall habitat conditions in Riparian Reserves associated with the Canyon Creek and Boulder Creek Lakes trails.

5. Design Criteria

Design criteria and monitoring necessary for protection of aquatic and riparian resource and water quality are identified below.

1. Implement Best Management Practices applicable to trail construction and decommissioning/rehabilitation. The use of Best Management Practices will enable the implementation of the proposed action or action alternatives in and around Riparian Reserves and prevent negative impacts to aquatic and riparian habitats and water quality. A complete description of each best management practice is provided in the publication 'Water Quality Management for National Forest System Lands in California'.20 BMP 7.1 – Watershed Restoration:21 The objective for BMP 7.1 is to repair degraded watershed conditions, and improve water quality and soil stability. Watershed restoration is a corrective measure to:

a. Improve ground cover density; b. Improve infiltration; c. Prevent excessive overland runoff and conserve the soil resource; d. Stabilize stream banks and stream channels; e. Improve productivity; f. Reduce flood occurrence and flood damage; g. Enhance economic, social and/or aesthetic values of the watershed; and h. Improve overall watershed function

20 USDA Forest Service, Pacific Southwest Region, Sept. 2000. Water Quality Management for Forest System Lands in California Best Management Practices. 21 USDA Forest Service, 2011. R5 FSH 2509.22 – Soil and Water Conservation Handbook, Chapter 10 – Water Quality Management Handbook.



There are many other BMP’s that have information that could be applicable to the proposed action, however these BMP’s are focused on roads and OHV trails and not intended for direct application to trails that are designed for hiker and stock use. Refer to FSH 2509.22 – Soil and Water Conservation Handbook for information on these Best Management Practices. 22

2. In order to avoid damage to wet meadow habitats and impacts to water quality restrict implementation activities to periods when runoff is not occurring on new and existing trail segments.

3. When implementing trail construction activities apply standards described in Forest Service

handbook 2309.18 - Trail Management Handbook.23

22 USDA Forest Service, 2011. R5 FSH 2509.22 – Soil and Water Conservation Handbook, Chapter 10 – Water Quality Management Handbook. 23 USDA Forest Service, 2008. FSM 2309.18 – Trails Management Handbook.



Map 1: Segment Locations