Environmental Assessmenta123.g.akamai.net/7/123/11558/abc123/forestservic...Hilton Lakes and Hilton...

Environmental Assessment

Hilton Lakes and Hilton Creek Trail Project

USDA Forest Service, Inyo National Forest

White Mountain Ranger District

Inyo and Mono Counties, California

January, 2012

Hilton Lakes and Hilton Creek Trail Project Environmental Assessment

Table of contents

Chapter 1 Purpose and Need for Action .................................................................................................... 1

1.1 Summary of proposed action .......................................................................................... 1

1.2 Document Structure ........................................................................................................ 1

1.3 Description of project area .............................................................................................. 2

1.4 Purpose and need ............................................................................................................ 4

1.5 Decision to be made ........................................................................................................ 7

1.6 Public Involvement and Native American Consultation .................................................. 7

1.7 Lahontan Regional Water Quality Control Board Requirement ...................................... 7

Chapter 2 Description of Alternatives ........................................................................................................ 8

2.1 Introduction ..................................................................................................................... 8

2.2 Alternatives: No Action and Proposed Action ................................................................. 8

2.3 Comparison of Alternatives ........................................................................................... 15

Chapter 3 Environmental Consequences ................................................................................................. 17

3.1 Introduction ................................................................................................................... 17

3.2 Effects to Water Quality: No Action and Proposed Action ............................................ 22

3.3 Effects to Soils: No Action and Proposed Action ........................................................... 26

3.4 Effects to Wilderness Character: No Action and Proposed Action ................................ 27

3.5 Effects Relative to Significance Factors ......................................................................... 31

Chapter 4 List of Persons Consulted ........................................................................................................ 36

4.1 Environmental Assessment Preparers ........................................................................... 36

4.2 References cited ............................................................................................................ 36

Chapter 5 Appendices .............................................................................................................................. 38

Appendix A: Description of Trail Prescriptions.................................................................................. 38

Appendix B: Project Site Prescriptions ............................................................................................... 39


List of Tables

Table 1. Trail Fundamentals: The Proposed Action’s Trail Fundamentals: management

guidelines for trail design, construction, maintenance, and use.

Table 2. Comparison of Alternatives: The No Action’s and Proposed Action’s effectiveness at

meeting project objectives.

List of Figures

Figure 1. Project Area Map

Figure 2. Watershed Boundary Map

Figure 3. Hilton Lakes Trail: project sites 1-22

Figure 4. Hilton Creek Trail: project sites 23-27

Figure 5. Hilton Creek Trail: project sites 28-44; Hilton Lake #2 Spur Trail: project sites 45-47


Chapter 1 Purpose and Need for Action

1.1 Summary of proposed action

The Inyo National Forest, White Mountain Ranger District, proposes to conduct a trails project

in the Hilton Creek and Rock Creek watersheds. The proposed project area encompasses the

trail corridor of four Forest System Trails: the Hilton Creek Trail (trail #2942); the Hilton Lakes

Trail (trail #2904); the Hilton Cut-off Trail (trail #2904B); and the Hilton Lake #2 Spur Trail

(trail #2942B). Most of the project area is located within the John Muir Wilderness, with a short

section of the Hilton Lakes Trail located outside of wilderness.

The Forest Service has determined that the wilderness character in the project area could be

enhanced by reducing trail-related impacts to natural resources. The project is intended to reduce

these impacts through five types of activities: 1) install stream channel protection treatments to

prevent trail erosion at stream crossings; 2) reroute a section of the Hilton Lakes Trail to a more

sustainable alignment and rehabilitate the abandoned section of trail; 3) install trail stabilizing

structures on incised or eroding sections of trail; 4) reconstruct deteriorating section of trail

causeway to protect meadows and seasonally wet areas; 5) reduce the width of over-widened

trail sections to protect vegetation and soils. Trail prescriptions are described in more detail in

Appendix A.

The proposed project is consistent with the trail management direction of the 2001 Ansel Adams,

John Muir, and Dinkey Lakes Wilderness Management Plan. The constructed trail features and

structures would be the minimum necessary to improve water drainage from trails, and protect

stream crossings and meadows from trail-related impacts. All aspects of this project would be

implemented with traditional (non-motorized) hand tools.

The Forest would have to secure funding before project implementation could begin. The

earliest starting date for the project would be July 2012. Depending on available funding, the

project would be completed over the course of several summer seasons.

1.2 Document Structure

This document is a project level Environmental Assessment. The Forest Service has prepared

this Environmental Assessment in compliance with the National Environmental Policy Act

(NEPA) and other relevant Federal and State laws and regulations. This Environmental

Assessment discloses the direct, indirect, and cumulative environmental impacts that would

result from the Proposed Action and No Action alternatives. The document is organized into four

Chapters:

1. Purpose and Need for Action: This section includes information on the project proposal, the

purpose of and need for the project, and the agency’s proposal for achieving that purpose and

need. This section also details how the Forest Service informed the public of the proposal and

how the public responded.


2. Description of the Two Alternatives: This section provides a description of the agency’s

Proposed Action for achieving the project’s purpose, and the No Action Alternative. This

section also provides a table that summarizes how well each alternative meets project objectives.

3. Environmental Consequences: This section describes the environmental effects of

implementing the Proposed Action and No Action Alternatives. This analysis is organized by

the two alternatives, and discusses each alternative’s effects to water quality, soils, and

wilderness character. The existing conditions in the project area are summarized first, followed

by a description of the effects on the resource under each alternative.

4. List of Persons Consulted: This section provides a list of Forest Service staff who prepared

the environmental assessment.

There are two appendices. Appendix A describes the prescriptions or trail treatments that would

be used if the Proposed Action were selected. Appendix B summarizes the existing condition at

the forty seven project sites, and the prescription proposed for each project site.

Additional documentation, including more detailed analyses of project-area resources, may be

found in the project planning record located at the White Mountain Ranger District Office in

Bishop, California.

1.3 Description of project area

The Hilton Lakes and Hilton Creek Trail Project area is located approximately twenty miles

northwest of Bishop, California in the Sierra Nevada Mountains (see figure 1).

Figure 1. Project Area Map


The project area includes portions of the Hilton Creek and Upper Rock Creek HUC 6 watersheds

(see Figure 2). The project area consists of forty seven separate sites or trail sections along 11.35

miles of four Forest System Trails: the Hilton Creek Trail (trail #2942); the Hilton Lakes Trail

(trail #2904); the Hilton Cut-off Trail (trail #2904B); and the Hilton Lake #2 Spur Trail (trail

#2942B). Most of the project sites (forty one) are within the Hilton Analysis Unit of the John

Muir Wilderness. Six project sites are in non-wilderness lands within the Rock Creek-Pine

Creek Management Area. In general, the project area boundary is a 150 feet wide corridor (75

feet on each side of the trail) at trail stream crossings or along trail sections proposed for project

work. The causeways and several of the perennial crossings would have a 600 feet wide corridor

because these treatments require a larger source area for materials.

Figure. 2 Hilton Creek and Upper Rock Creek Watersheds

This project area was chosen because the Forest would like to address trail-related effects to

watershed conditions throughout the Hilton Creek and the Upper Rock Creek watersheds. The

proposed project will address Forest System Trail conditions throughout the Hilton Analysis

Unit.


1.4 Purpose and need

The overall goal of the project is to protect watershed conditions in the project area. The purpose

is to minimize the impacts of the wilderness visitor on the immediate environment to protect the

natural qualities of wilderness character. This project would not change the existing types and

level of use in the Hilton Analysis Unit.

1.4.1 Need

The need for this project was established through a Forest Service interdisciplinary team

evaluation of trail conditions in the two watersheds during 2009-2011. The interdisciplinary

team concluded there are four types of existing resource conditions that do not meet Forest

standards and guidelines for trails in wilderness.

1. Trails in the project area cross a perennial stream at ten locations and an intermittent stream

at nine locations. Each crossing has some degree of stream bank erosion, stream channel

widening, and diminished riparian vegetation. The trails currently lack the type of structures

that would protect the trail and stream banks from further erosion and widening.

2. Trail conditions are affecting hydrologic connectivity in three ways. First, there are four

sections of causeway over meadows and wet areas on the Hilton Creek Trail that are

deteriorating after a 30 year life span. The causeways, totaling 1,050 feet in length, require

replacement to maintain their effectiveness at allowing surface water to flow past the trail.

Second, between Lake #3 and Lake #4, a section of the Hilton Creek Trail 250 feet in length

is aligned through a wet meadow, which may disrupt natural water flow paths. Third, the

Hilton Lakes Trail is intercepting stream flows at three stream crossings.

3. Sections of the Hilton Lakes and Hilton Creek Trails totaling 9,750 feet have become over-

widened over time. The widening process has damaged vegetation along the trail corridor

margins, and the soils have become susceptible to erosion.

4. Sections of the Hilton Lakes, Hilton Creek and Hilton Lakes #2 Spur Trail totaling 7,000 feet

in length are either on steep grades or are incised. These sections, which lack trail stabilizing

structures, have had soils eroded from their tread and are susceptible to further erosion.

1.4.2 Project objectives

Objectives: The Forest has identified four project objectives that will serve as the criteria to

compare how well the two alternatives meet the overall project purposes. The management

direction that is the source for each objective is referenced as “Direction” below. For each

objective, an indicator has been chosen to measure how well the alternatives meet the project

objectives.


Objective 1: Protect water quality by improving stream bank conditions at trail stream crossings.

Direction: Design (stream crossings) to maintain width:depth ratio of the stream (source: Inyo

National Forest Land and Resource Management Plan [LRMP], Watershed

Management Direction, pg.96).

Indicator: Over-widened stream banks at stream crossings.

Measure: Area of over-widened stream banks (width to depth ratio exceeds natural

conditions) at each project site.

Objective 2: Protect water quality by stabilizing eroding trail sections.

Direction: Stabilize all areas disturbed by management activities to minimize soil erosion.

(source: LRMP Watershed Management Direction, pg. 95).

Indicator: Trail sections susceptible to erosion of trail tread.

Measure: Proportion of trail sections with steeper grades (> 15%) that lack erosion control

structures or is incised.

Objective 3: Restore hydrologic connectivity in areas where the trail may be interrupting surface

and subsurface water flow.

Direction: Maintain and restore the hydrologic connectivity of streams, meadows, wetlands,

and other special aquatic features by identifying roads and trails that intercept,

divert, or disrupt natural surface and subsurface water flow paths. Implement

corrective actions where necessary to restore connectivity. (Source: Sierra Nevada

Framework Plan Amendment standard and guideline 100, pg. 63).

Indicator: Trail conditions that disrupt hydrologic connectivity.

Measure: 1) Proportion of causeways in watershed maintaining connectivity.

2) Proportion of trails in project area in a meadow.

3) Proportion of stream crossings that intercept stream flow.

4) Number of trail-related head cuts in riparian areas within the project area.

Objective 4: Reduce trail width in over-widened areas to meet design standards for Trail Class 3

trails in wilderness.

Direction: Maintain system trails to meet management objectives for visitor use and resource

protection (source: 2001 Wilderness Management Plan, Trail Management

Direction, pg. 11).

Indicator: Vegetation and soil disturbance outside a trail’s designed clearing width.

Measure: Proportion of trail in project area that exceeds design guidelines for trail width.


1.4.3 Laws, Regulations, and Policies

The decision on this project will be made in accordance with a number of laws, regulations, and

Forest Service policies including:

The Wilderness Act of 1964 provides for the establishment of designated wilderness lands that

are to be protected for their ecological, geological, recreational, historic, scientific, education and

scenic values. Section 4(d) of the Wilderness Act states the Forest Service “shall be responsible

for preserving the wilderness character of the area and shall so administer such area for such

other purposes for which it may have been established as also to preserve its wilderness

character.”

The Endangered Species Act of 1973, as amended contains provisions to prevent the extinction

of any species that is in danger of extinction throughout all or a significant portion of its range.

Section 7 of the Act outlines procedures for interagency cooperation to conserve Federally listed

species and designated critical habitats.

The Clean Water Act of 1972, as amended contains provisions to restore and maintain the

chemical, physical, and biological integrity of the nation’s waters, and to protect beneficial use.

Executive Orders 11988 and 11990 direct federal agencies to avoid to the extent possible the

impacts associated with the destruction or modification of floodplains and wetlands. Agencies

are directed to avoid construction and development in floodplains and wetlands whenever there

are feasible alternatives.

The National Historic Preservation Act of 1966, as amended requires federal agencies to

identify and consider historic properties in Federal and federally assisted actions.

The Inyo National Forest Land and Resource Management Plan (1988) contains watershed

goals and wilderness management direction applicable to trail projects in wilderness.

The Sierra Nevada Forest Plan Amendment Record of Decision (2004) amended the Inyo

LRMP. The Record of Decision established Riparian Conservation Objectives, a set of six

objectives and their associated standards and guidelines that establish management direction for

Riparian Conservation Areas (defined as areas near water bodies and wetlands). The Riparian

Conservation Objectives were developed to protect water quality, aquatic and riparian habitats,

and stream, floodplain and watershed condition.

The 2004 Record of Decision also contains direction regarding the involvement of American

Indian Tribes, communities, and organizations in land management and for consideration of

traditional cultural values, uses and access.

The Sierra Nevada Management Indicator Species Amendment Record of Decision (2007)

requires the Forest to analyze the effects of proposed projects on management indicator species’

habitat.


The Record of Decision for Management Direction for the Ansel Adams, John Muir, and

Dinkey Lakes Wildernesses (2001) established management direction, including trail

management direction, for the John Muir Wilderness. The Record of Decision also established

limits to the number of daily entries into wilderness by non-commercial and commercial

overnight visitors to the Hilton Analysis Unit. Commercial pack stock outfitters also have limits

placed on the amount of day use and annual use to the Hilton Analysis Unit.

Forest Service Manual Section 2323 provides policy for management of Forest System trails in

wilderness.

Forest Service Handbook Section 2309.18 provides guidelines for trail project planning.

1.5 Decision to be made

The deciding official will review the Proposed Action and No Action alternatives, and, given the

purpose and need for the project and environmental effects, decide whether or not to implement

the proposed trail management activities.

1.6 Public Involvement and Native American Consultation

The Hilton Lakes and Hilton Creek Trails Project has been listed on the Forest’s Schedule of

Proposed Actions since January 2011. A scoping letter describing the Proposed Action was

mailed to sixteen individuals or agencies on August 19, 2011. One comment letter was received

during scoping by the California Regional Water Quality Control Board, which indicated a

Section 401 Permit from the agency would be required because the project would include soil

disturbing activities in waterways. No other potential issues or effects on resources were

identified by either agencies or the public.

Native American Tribes that claim ancestral home lands within the project area were consulted

pursuant to the American Indian Religious Freedom Act of 1978, Executive Order 13007

(1996), and under Section 101(d)(6)(B) of the National Historic Preservation Act of 1966 as

amended. Official letters regarding the Hilton Lakes and Hilton Creek Trail project were mailed

to the following Paiute Tribes that claim ancestral lands within the project area:

Big Pine Tribe of Owens Valley, Big Pine, Ca.

Bishop Paiute Indian Tribal Council, Bishop, Ca.

Fort Independence Community of Paiute Indians, Independence, Ca.

Lone Pine Paiute-Shoshone Reservation, Lone Pine, Ca.

No issues or concerns have been brought forward by any of the four Tribes.

1.7 Lahontan Regional Water Quality Control Board Requirement

The Water Quality Control Plan for the Lahontan Region (Basin Plan) contains policies that area

used with other laws and regulations to protect water quality within the Lahontan Region. The


Regional Water Quality Control Board indicated in their response to the scoping letter their

agency would require a Section 401 water quality certification for this project.

Chapter 2 Description of Alternatives

2.1 Introduction

Since no relevant environmental issues were raised by the public that would have been used to

develop additional alternatives to the Proposed Action, only two alternatives will be compared in

this environmental assessment: the No Action and the Proposed Action. The No Action

Alternative allows the existing trail conditions in the Hilton Analysis Unit to continue. The

Proposed Action was developed by an interdisciplinary team during 2009-2011. The team used

a problem assessment approach to evaluate trail conditions in the project area. The Proposed

Action is the Forest’s recommended action for addressing existing resource impacts related to

trail conditions. The management of visitors would remain the same with the selection of either

alternative. There would be no change to the amounts of commercial or non-commercial use

allowed in the area, and no change to the areas within the Hilton Analysis Unit where

commercial pack stock would be allowed to travel.

2.2 Alternatives: No Action and Proposed Action

2.2.1 No Action

If the No Action alternative is selected, no stream fords at perennial stream crossings or stream

bank stabilizing structures at intermittent stream crossings would be constructed. There would

be no additional trail stabilizing structures along incised or eroding sections of trail, and no

replacement of causeway structures.

Routine maintenance of the trails consistent with the trail Service Level listed in the 2001

Wilderness Management Plan could continue. Routine maintenance includes: cleaning and

repairing drainage structures; clearing the trail tread of obstacles such as rock, slough, fallen

trees, and brush; maintain trail tread width and removing berms from the outside edge of the

trail; and incidental replacement or repairs to existing trail structures such as steps and

causeways.

2.2.2 Proposed Action

Five types of project activities are proposed for the Hilton Lakes, Hilton Creek and Hilton Lakes

#2 Spur Trail:

1. Install stream channel protection treatments at twenty locations where a trail crosses a

stream. Three types of treatments are proposed, based on stream size and the existing trail

conditions:

□ Stream fords would be constructed at nine perennial stream crossings. The stream

channel width would be reduced from the existing over-widened condition to one more


closely matching nearby natural conditions. The stream banks at the trail entries would be

protected from erosion by “armoring” the stream entries with rocks from local sources

within the project area.

□ To provide additional protection to riparian vegetation and soils, short trail re-routes or

rock causeways would be constructed at the approaches to four of the perennial crossings.

One of the stream crossings on the Hilton Lakes Trail would include a wooden deck log

bridge approximately twenty feet long.

□ Trail and stream bank stabilization structures would be installed at nine intermittent

stream crossings.

2. Construct a re-route of a section of the Hilton Lakes Trail approximately 4,000 feet in length

that follows the current alignment of the Hilton Bypass Trail. Abandon a section of the

Hilton Lakes Trail 3,000 feet in length, and apply restoration treatments to the abandoned

section. Apply rehabilitation treatments to a perennial stream channel at one stream crossing

on the abandoned trail section.

3. Install trail stabilizing structures to prevent soil erosion on approximately 7,000 feet of trail.

Trail stabilizing structures would be installed where necessary to remove flowing water from

the trail.

4. Reconstruct four segments of existing causeway totaling 1,050 feet in length. Replace an

existing wooden deck log bridge that is in the middle of one causeway.

5. Reduce the trail width along 6,800 feet of the Hilton Lakes and Hilton Creek Trails from its

existing over-widened condition to a width that meets the Forest Service design guidelines of

60-78 inches for trail clearing width. Use rocks or logs to reduce trail width. Apply

restoration treatments to naturalize the area beyond the trail that have been impacted by

visitors.

Project work is proposed for forty seven sites along the Hilton Lakes Trail, the Hilton Creek

Trail, the Hilton Lakes Bypass Trail, and the Hilton Lake #2 Spur Trail. The project sites

include twenty stream crossings and twenty six sections of trail in the project area (see figures 3-

5). The design of the protection treatment or prescription for each site is based on the soils,

hydrological conditions, use levels, and potential for erosion. Appendix A contains descriptions

of the seven types of trail treatments or prescriptions. Appendix B contains a list of project sites,

a summary of the existing conditions at each site, and the type of treatment prescribed for each

site.


2.2.3 Proposed Action management requirements

The following management requirements were developed through the interdisciplinary team

process, and would apply to the Proposed Action:

1. The Forest Hydrologist identified four measures from Water Quality Management for Forest

System Lands in California - Best Management Practices (2000) that would be applied to the

project:

□ Erosion Control Plan (Practice 2-2): Forest watershed staff would develop and provide

oversight of this plan to minimize erosion and sedimentation during project

implementation.

□ Timing of Construction Activities (Practice 2-3): Project implementation would be

scheduled after the season of peak snowmelt runoff. The trail crew leader would also

cease project construction work during rain events.

□ Protection of Water Quality within Developed and Dispersed Recreation Areas (Practice

4-9). This BMP is a corollary of the Erosion Control Plan, and prohibits the placing of

sediment in or near a stream. Forest watershed staff would develop this control, which

would be implemented by the trail crew leader when working adjacent to streams.

□ Protection of Wetlands (Practice 7-3): Watershed staff would develop measures to

minimize impacts to wetlands during causeway replacement. Watershed staff would

provide oversight during bridge replacement at site 29 to minimize water quality impacts

at this site.

2. All borrow sites used as the source of rock or gravel for project sites would be rehabilitated.

Trail crews would re-contour borrow sites to match natural topography, and duff and woody

debris would be spread to promote revegetation.

3. Heritage protection measures: project site work and borrow pits would avoid disturbing any

trees with dendoglyphs/carvings; all project materials between project site 41 and site 44

would only be removed from the south side of the trail.

4. There would be a limited operating period for work on sites 29, 30, 32 to protect nesting

northern goshawks from disturbance by project activities. The limited operating period when

no project work can occur is February 15 through August 15 each year.

5. A Forest Botanist would be on site during project implementation at sites 35 and 37 to ensure

project work avoids disturbing sensitive plants near those sites.

6. Up to 30 trees would be felled to provide log stringers for causeway reconstruction. The trail

crew would utilize beetle-killed trees for the log stringers where possible. No more than

three snags per acre would be removed.

7. There would be post-project monitoring of treatment effectiveness by the Forest Hydrologist

one year after the completion of the project.


2.2.4 Trail management objectives

Forest Service Manual 2353.1, Administration of National Forest System Trails, indicates the

Forest identify Trail Management Objectives, including: 1) the five Trail Fundamentals; 2)

Recreation Opportunity Spectrum classifications; 3) trail design criteria; 4) travel management

strategies; and 5) maintenance criteria for system trails. The trail fundamentals for each trail are

indicated below in Table 1 and would not be changed by the Proposed Action. The 2001

Wilderness Management Plan utilized a “recreation category” classification instead of a

recreation opportunity spectrum classification; all project trail sections in wilderness are in

recreation category “2”. The 3,000 foot section of the Hilton Lakes Trail outside of wilderness is

within the Recreation Opportunity Spectrum classification of semi-primitive (1988 Inyo National

Forest LRMP). The trail design would follow the general criteria for Trail Class 2 and Trail

Class 3 Trails indicated in Forest Service Handbook Section 2309.18, Chapter 14.2, Exhibit 01.

The maintenance criteria for the trails would apply the considerations listed in FSH 2309.18,

Chapter 18, Exhibit 0.1.

The proposed action would not develop additional trails in the Hilton Analysis Unit, nor change

the level of development of the trails. The Trail Class for each trail would remain consistent

with the Service Levels contained in the 2001 Trails Inventory (2001 Ansel Adams, John Muir

and Dinkey Lakes Wildernesses Final Environmental Impact Statement, Appendix C). Project

work on the Hilton Creek Trail between Lake 3 and Lake 4, and on the Hilton Lake #2 Spur Trail

would be to protect water quality and hydrologic connectivity, and would not include

prescriptions to build the trails to stock standards.

Table 1. Trail Fundamentals The Trail Fundamentals for trails in the project area are the management guidelines for trail design, construction, maintenance, and use.

Trail Fundamentals

Hilton Lake Trail

Hilton Creek Trail Trailhead to jct.

with Hilton Lakes Trail

Hilton Creek Trail Jct. with Hilton

Lakes Trail to Lake 4 terminus

Hilton Lake #2 Spur Trail

Trail Type Standard Terra Trail Standard Terra Trail Standard Terra Trail Standard Terra Trail

Trail Class Trail Class 3: Developed

Trail Class 3: Developed.

Trail Class 2: Moderately Developed

Trail Class 2: Moderately Developed

Managed Use Hiker, Pack and Saddle

Hiker, Pack and Saddle



Designed Use Pack and Saddle Pack and Saddle Hiker Hiker


Trail Fundamentals

Hilton Lake Trail

Hilton Creek Trail Trailhead to jct.

with Hilton Lakes Trail

Hilton Creek Trail Jct. with Hilton

Lakes Trail to Lake 4 terminus


Design Parameters

Tread width: 12” to 24”. May be up to 48 ‘’ at stream fords.

Tread width: 12” to 24”. May be up to 48 ‘’ at stream fords.

Tread width: 6” to 18”

Tread width: 6” to 18”

Trail clearing width: 6 feet to eight feet.

Trail clearing width: 6 feet to eight feet.

Trail clearing width: 6 feet

Trail clearing width: 6 feet

Structures may be common & substantial; natural or constructed fords; bridges as needed for resource protection.

Structures may be common & substantial; natural or constructed fords.

Structures adequate to protect trail infrastructure & resources

Structures adequate to protect trail infrastructure & resources

2.3 Comparison of Alternatives

This section compares how well the No Action and the Proposed Action achieve project

objectives. Table 2 on the page below displays the four project objectives. For each project

objective, the Forest has selected an indicator of resource conditions and one or more measures

for the indicator (Section 1.4.2). The projected measure for each indicator is displayed in the No

Action and Proposed Action columns. The Proposed Action more effectively meets the four

project objectives than the No Action Alternative.


Table 2. Comparison of Alternatives The No Action’s and Proposed Action’s effectiveness at meeting project objectives.

Project Objective Indicator & Measure No action Proposed action

1: Protect water quality by improved structure and condition of stream banks.

Over-widened stream banks at stream crossings. Measure: Area of over-widened stream banks (width to depth ratio exceeds natural conditions) at each project site.

Currently about .10 acre at each crossing affected by over-widened stream banks & diminished vegetation. Would continue trend towards larger area of over-widened stream banks & diminished vegetation.

Would reduce over-widened area from .10 acre to approximately .02 acre at each stream crossing. Stream crossings would match more closely natural width to depth ratio; stabilized banks would promote revegetation.

2: Protect water quality by stabilizing eroding trail sections.

Trail sections that are susceptible to erosion. Measure: Proportion of trail sections with steeper grades (> 15%) that lack erosion control structures or is incised1.

12% of the total length of system trails in the project area would continue to be susceptible to erosion.

No trail sections with steeper grades would lack erosion control structures. In addition, the abandoned section of Hilton Lakes trail 3,000 feet in length would be stabilized.

3: Maintain or restore hydrologic connectivity of streams and meadows.

Trail conditions disrupting connectivity. Measure a: Proportion of causeways in watershed maintaining connectivity2.

Downward trend in connectivity along 87% of causeway length in project area, with the trail more likely to interrupt surface and subsurface water flows.

100% of total causeway length in project area would maintain hydrologic connectivity.

Measure b: Proportion of trails in project area in a meadow3.

3% of the total length of trails in the project area will remain aligned in seasonally wet meadows4.

2.6% of the total length of trails in the project area will remain aligned in seasonally wet meadows5.

Measure c: Proportion of stream crossings that intercept stream flow.

15% of stream crossings will continue to intercept stream flow.

No stream crossings will intercept stream flow.

Measure d: Number of head cuts that are associated with trails.

Three existing trail-related head cuts in project area remain untreated, with the potential to erode further.

Three existing head cuts in the project area stabilized.


Project Objective Indicator & Measure No action Proposed action

4: Reduce trail width in over-widened areas to meet design guidelines for Trail Class 3.

Vegetation and soil disturbance outside the trail corridor. Measure: Proportion of trail in project area that exceeds design guidelines for trail width .

Seventeen percent of trail length (9,750 feet) in project area exceed design guidelines, with continued vegetation damage and soil disturbance.

One hundred percent of trail length in project area treated to meet design guidelines6.

1 Approximately 7,000 feet of trail in the project area are on steeper grades and lack erosion control

structures.

2 There are five sections of causeway in the project area, with a total length of 1,200 ft. Four sections,

totaling 1,050 feet in length, are in a deteriorating condition.

3 Approximately 850 feet of the Hilton Creek Trail is aligned through a seasonally wet meadow and does

not have a causeway structure. Approximately 1,000 feet of the Hilton Lake #2 Spur Trail is aligned

through a seasonally wet meadow; there are no causeways on this trail.

4 850 feet of the Hilton Creek Trail and 1,000 feet of Hilton Lake #2 Spur Trail are aligned in a seasonally

wet meadow.

5 Approximately 250 feet of the Hilton Creek Trail will be re-routed out of a meadow; 600 feet of trail

will remain aligned in a seasonally wet meadow. 1,000 feet of Hilton Lake #2 Spur Trail would remain

aligned in a seasonally wet meadow.

6 6,750 feet of the currently 9,750 feet of over-widened trail would be treated. In addition, the 3,000 feet

of Hilton Lakes Trail that would be abandoned would be treated with the trail rehabilitation prescription.

Chapter 3 Environmental Consequences

3.1 Introduction

This chapter is organized by the effects to water quality (section 3.2), soils (section 3.3), and

wilderness character (section 3.4) for the No Action and Proposed Action Alternatives. The

Forest Service has identified these three resources as the relevant resources for analysis based on

the project need and project objectives. Relevant resources are the resources that may be affected

by the implementation of either the No Action or Proposed Action. Effects to other resources

and the ten significance factors are disclosed in section 3.5.

Terminology: The effects on resources or wilderness character are described in terms of the type

(i.e. beneficial or adverse effect), context (the areal extent of effect), duration, and the intensity


of effect. Beneficial effects would improve resource condition or wilderness quality. Adverse

effects are those that are unfavorable.

Intensity terminology

Negligible: There would be no detectable effect on a resource or a quality of wilderness

character.

Minor: Effects to a resource or one or more qualities of wilderness character would be

detectable; effects would be localized to the immediate area around project sites,

and would not be detectable elsewhere in a watershed.

Moderate: Effects on a resource or one or more qualities of wilderness character would be

appreciable; effects would extend beyond the immediate area around project sites;

and effects would occur in multiple areas within a watershed.

Major: Effects would substantially alter a resource or one or more qualities of wilderness

character; effects would be observed over a larger area (i.e. wilderness-wide).

Duration terminology

Temporary: Effects would occur only during implementation activities at a project site, and

would not persist for more than one day after construction is completed. The

expected duration of implementation activities at stream crossings is one to five

days at intermittent stream crossings, and up to twenty days at each of the four

largest perennial crossings in the project area.

Short term: Effects would occur during implementation and persist after construction is

completed. After project completion, the resulting effects would persist over a

time period from one month to one year.

Medium term: After project completion, the resulting effects would persist over a time period

from one year to ten years.

Long term: After project completion, the resulting effects would persist for more than 10

years.

3.1.1 Overview of existing conditions

The basic alignment of the trails in the project area has been in place for many years. Summer

grazing of livestock during the first half of the twentieth century probably established the general

alignment of the current trail system. Prior to wilderness designation, a mine operator in the

Hilton Creek drainage maintained an access road to the mine. A section of that access road is

now the current alignment of the Hilton Creek Trail in the northern portion of the project area.

The early trail system provided access to several resorts that operated in the Hilton Lakes area

prior to the designation of the John Muir Wilderness in 1964. At some point during the 1960s

and 1970s, sections of the trails were realigned to reduce trail grades and better protect resources.


During the early 1980s the forest constructed the existing causeways, wooden decked log bridge,

and log crossing for hikers on the Hilton Creek Trail. During the mid-1990s, the Forest added

trail stabilizing structures on sections of the Hilton Lakes Trail and Hilton Creek Trail. In 2001,

the Forest took additional measures to stabilize the Hilton Creek Trail between Lake 2 and Lake

3.

Analysis process: An interdisciplinary (idt) team employed the problem assessment approach

described in Marion and Leung (2001) to evaluate potential project sites for inclusion in the

Proposed Action between 2009 and 2011. The interdisciplinary team re-evaluated conditions at

stream crossings and trail sections that had been evaluated by the Forest during 1999 and 2001.

The team assessed the changes in trail conditions over the ten year time period and trends in

impacts to water quality and soils. The Proposed Action was developed to address the existing

resource conditions.

Existing water quality and soils conditions:

1. Stream bank conditions at trail stream crossings: Trail stream crossings at ten perennial

streams and nine intermittent streams have over-widened stream banks, diminished riparian

vegetation, and decreased surface water shade (see figures 3-5 for the location of stream

crossings). The amount of channel widening at perennial stream crossings varies from

several feet at the smaller streams to nearly fifty feet at site 7. The average area affected by

over-widened streambanks is 0.1 acre at each stream crossing. Because stream banks are

continuing to widen at stream crossings, stream bank conditions are in a downward trend.

2. Trail conditions on steeper grades: There are nine sections of trail totaling 7,000 feet in

length on steep grades (more than 15% grade) that currently do not have trail stabilizing

structures. Four sections are located on the Hilton Lakes Trail (sites 4, 15, 21 and 22); four

sections are located on the Hilton Creek Trail (sites 26, 27, 40 and 44); and one section is

located on the Hilton Lake #2 Spur Trail (site 45). Two of the sections on the Hilton Creek

Trail (sites 26 and 27) are also incised between one and two feet deep. The seven remaining

sections have degraded trail tread that exhibit signs of on-going soil erosion from the trail.

3. Hydrologic connectivity of meadows and streams:

□ The Hilton Creek Trail has five sections of causeway totaling 1,500 feet in length that

cross wet meadows or seasonally wet soils in the project area. Four causeway sections,

totaling 1,050 feet in length, are in a deteriorating condition and they are losing their

ability to allow surface and subsurface water to flow past the trail (sites 29 and 35).

□ Several sections of the Hilton Creek Trail totaling 850 feet in length are aligned through

seasonally wet meadows (see figure 4 for the location of meadows in the project area).

□ There are three stream crossings where the Hilton Lakes Trail is intercepting stream

flows and water is diverted down the trail for a short distance (sites 5, 13 and 14).


□ There are head cuts in meadows adjacent to the trail in two locations (two head cuts at

site 29, and site 41).

4. Over-widened trail sections: There is existing vegetation damage and disturbed soils along

9,700 feet of the Hilton Lakes and Hilton Creek Trails caused by visitors traveling outside

the trail tread. Four sections of the Hilton Lakes Trail (sites 2, 8, 11 and 20) and two sections

of the Hilton Creek Trail (sites 23 and 24) appreciably exceed the design guidelines for the

trail width of a Trail Class 3 trail (Table 1). The width of the area disturbed varies across the

project area. Sections of the Hilton Lakes Trail (sites 18 and 20) contain disturbed soils areas

more than twenty five feet in width. Most other sections of over-widened trail are ten to

fifteen feet in width. Forest design guidelines indicate an eight foot wide trail clearing for

Trail Class 3 trails, with occasional wider areas to allow stock parties to pass each other.

Existing conditions for wilderness character

Wilderness character is defined by four qualities: natural, untrammeled, undeveloped, and

opportunities for solitude or primitive and unconfined recreation.

Natural: The existing conditions for the indicators of the natural quality of wilderness character

applicable to this project are summarized by the existing conditions for water quality and soil

above.

Untrammeled and undeveloped: Neither the No Action nor Proposed Action alternatives would

affect the existing conditions for the untrammeled and undeveloped qualities, so they will not be

discussed in this document.

Opportunities for solitude or primitive and unconfined recreation: The indicators for this quality

applicable to the proposed project are: 1) trail crew presence; and 2) facilities that decrease self-

reliant recreation. Based on recent years’ trail maintenance funding levels, trail crews comprised

of four or five people camp and work in the project area for one to two weeks every third year.

The sight and sound of trail crews may affect some visitors’ perception of solitude. Trail crew

camping activities, however, do not affect the 2001 Wilderness Management Plan standards for

solitude, which have an indicator based on the number of occupied campsites within sight or

sound or a benchmark campsite. Because trail crews do not camp at the locations in the lakes

basin that are the typical destination for visitors, their camps are not within sight or sound of

other visitors’ camps.

There are existing causeway sections, a stock bridge, and a hiker log crossing on the Hilton

Creek Trail These trail facilities decrease self-reliant recreation to a degree because they reduce

the challenge of wilderness travel (although the primary purpose of the causeways and bridge is

to protect wetland areas, not to make travel easier). There are no facilities on the remaining nine

perennial stream crossings in the project area. There are a total of ten perennial stream crossings

in the project area.


3.1.2 Discussion on cumulative effects

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.

Cumulative impact can result from individually minor but collectively significant actions taking

place over a period of time (Council on Environmental Quality regulation 1508.7).

In order to understand the contribution of past actions to the cumulative effects of the proposed

action and alternatives, this analysis relies on current environmental conditions as a proxy for the

impacts of past actions. This is because existing conditions reflect the aggregate impact of all

prior human actions and natural events that have affected the environment and might contribute

to cumulative effects.

This cumulative effects analysis does not attempt to quantify the effects of past human actions by

adding up all prior actions on an action-by-action basis. There are several reasons for not taking

this approach. First, a catalog and analysis of all past actions would be impractical to compile

and unduly costly to obtain. Current conditions have been impacted by innumerable actions over

the last century (and beyond), and trying to isolate the individual actions that continue to have

residual impacts would be nearly impossible. Second, providing the details of past actions on an

individual basis would not be useful to predict the cumulative effects of the proposed action or

alternatives. In fact, focusing on individual actions would be less accurate than looking at

existing conditions, because there is limited information on the environmental impacts of

individual past actions, and one cannot reasonably identify each and every action over the last

century that has contributed to current conditions.

Additionally, focusing on the impacts of past human actions risks ignoring the important residual

effects of past natural events, which may contribute to cumulative effects just as much as human

actions. By looking at current conditions, we are sure to capture all the residual effects of past

human actions and natural events, regardless of which particular action or event contributed

those effects. Third, public scoping for this project did not identify any public interest or need

for detailed information on individual past actions. Finally, the Council on Environmental

Quality issued an interpretive memorandum on June 24, 2005 regarding analysis of past actions,

which states, “agencies can conduct an adequate cumulative effects analysis by focusing on the

current aggregate effects of past actions without delving into the historical details of individual

past actions.”

The cumulative effects analysis in this EA is also consistent with Forest Service National

Environmental Policy Act (NEPA) Regulations (36 CFR 220.4(f)) (July 24, 2008), which state:

“…With respect to past actions, during the scoping process and subsequent preparation of the

analysis, the agency must determine what information regarding past actions is useful and

relevant to the required analysis of cumulative effects….”


Finally, previous analyses that relied on catalogs of past actions did not identify any significant

cumulative effects to water quality and soils in the Hilton Creek and Rock Creek watersheds.

The cumulative effects analyses in the Trail and Commercial Pack Stock Management in the

Ansel Adams and John Muir Wilderness Final Environmental Impact Statement, 2005 (2005

FEIS) (pp. IV 259-277 and IV 368-373) were based on a catalog of past, present, and reasonably

foreseeable actions overlaps the current Proposed Action in space and time. The 2005 FEIS

indicated that past and present actions have caused some local increases in compacted soil,

stream bank trampling, stream incision, and increased sedimentation into surface water that

would continue. However, the discussion on cumulative effects for that alternative concluded

there would be no cumulative impacts to water quality and soils in the Hilton Creek and Rock

Creek watersheds. For these reasons, the analysis of past actions in this EA is based on current

environmental conditions.

Cumulative Effects Analysis Areas

The Cumulative Effects Analysis Area for water quality, soils, and the natural quality of

wilderness would be same as the area of direct and indirect effects because any effects to water

quality or soils from the proposed action would be negligible beyond this area. Because there are

no other present or reasonably foreseeable actions that would affect the Cumulative Effects Area,

the direct and indirect effects of the No Action and Proposed Action will describe the full

increment of effects to water quality and soils. The Cumulative Effects Area for wilderness

character (opportunities for solitude and primitive and unconfined recreation) is the Hilton

Analysis Unit. The rationale for the Cumulative Effects Area for this quality of wilderness

character is that visitors’ experience of solitude or primitive and unconfined recreation in other

areas of the John Muir Wilderness outside of the Hilton Analysis Unit would not be affected by

any actions within the Hilton Analysis Unit.

3.2 Effects to Water Quality: No Action and Proposed Action

The effects to water quality will be discussed through indicators and measures associated with

the first three project objectives.

Indicator #1- Stream bank conditions at stream crossings: The measure of steam bank

conditions is the area of over-widened stream banks and diminished riparian vegetation as

compared to reference reaches upstream of each crossing.

Indicator #2- Trail tread sections that are susceptible to erosion: The measure of

susceptibility to erosion is the length of trail sections with steeper grades (more than 15% grade)

that lack erosion control structures or is currently incised.

Indicator #3- The hydrologic connectivity of streams and meadows: Four measures for this

indicator are applicable to this project. The measures provide a means of assessing the areal

extent that trails may be affecting the natural flow paths of water in project area.


Measure a: Proportion of causeways in watershed maintaining connectivity.

Measure b: Proportion of trails in project area in a meadow.

Measure c: Proportion of stream crossings that intercept stream flow.

Measure d: Number of trail-related head cuts in riparian areas within the project area.

The analysis boundary for direct and indirect effects to water quality includes:

The average .10 acre area adjacent to trail stream crossings that is currently over-widened.

The rationale for this boundary is that the over-widened area of stream crossing is the source

of sediment to the streams.

The stream reach approximately 1,000 feet downstream from perennial and intermittent

stream crossings. The rationale for this boundary is that sediment entering a stream may

cause turbidity downstream for a distance up to 1,000 feet.

The meadows and wetlands through which the trails are aligned. The rational for this

boundary is that trails may cause localized impacts to a meadow’s connectivity with the

watershed, but these effects are not felt beyond the meadow through which the trail is

aligned.

3.2.1 Direct and Indirect Effects of No Action on Water Quality

There would be a minor adverse effect of long term duration in the project area to water quality.

Project area conditions would not meet the standards and guidelines for Riparian Conservation

Areas as measured by the following three indicators:

1. Area of over-widened stream banks (width to depth ratio exceeds natural conditions:

There would continue to be a downward trend in conditions at the twenty sites where a trail

crosses a stream. The area affected by stream bank widening currently averages .10 acre at each

of 20 stream crossings. Streambanks would continue to widen beyond natural conditions from

the combination of visitor use and scouring stream flows. Impacts to vegetation in riparian area

adjacent to trail stream crossings would continue, with gradually diminished shade cover over

the stream banks at the crossings. Soils would continue to erode from trails and streambanks,

and contribute excessive fine sediment to stream channels.

2. Trail sections susceptible to erosion:

There would continue to be a downward trend in the condition of the trail tread along eight

sections of trail totaling 6,000 feet in length. Soils would continue to erode from trail sections on

steep grades or sections where trail incision is already occurring. Along trail sections that are

incised, heavy rain or runoff events could channel eroded sediment down trails to reach stream

channels. A total of 12% of the total length of system trails in the project area would continue to

be susceptible to erosion.


3. Hydrologic connectivity of streams and meadows:

Measure a - Proportion of causeways in watershed maintaining connectivity: The four sections of

causeway totaling 1,050 feet in length (87% of causeways in project area) would continue to

deteriorate and would eventually lose their ability to allow surface and subsurface water to flow

past the trail. Continued travel over the muddy trail tread on deteriorated structures would likely

cause additional sediment to reach waterways.

Measure b - Proportion of trails in project area in meadows: Sections of the Hilton Creek Trail

totaling 850 feet in length and 1,000 feet of the Hilton Lakes #2 Spur Trail (3% of the total

length of trails in the watershed) would continue to be aligned through seasonally wet meadows.

Trails in meadows have the potential to adversely affect connectivity by compacting soils,

channeling surface water flows, and creating head cuts. Muddy trail tread in meadows is also

more susceptible to erosion.

Measure c - Proportion of stream crossings that intercept flow: Three of twenty (15%) stream

crossings along the Hilton Lakes Trail would continue to intercept stream flows, which would be

a disruption of the connectivity of these streams to the watershed.

Measure d - Number of head cuts that are associated with trails: Three head cuts adjacent to the

Hilton Creek Trail would continue to pose of risk of eroding and contributing sediment to

streams.

3.2.2 Cumulative Effects of No Action on Water Quality

There would be no cumulative effects to water quality because there are no other existing

environmental conditions, ongoing projects, or reasonably foreseeable projects with effects to

water quality that would overlap in space and time and have the same type of effects as the No

Action Alternative.

3.2.3 Direct and Indirect Effects of Proposed Action on Water Quality

During project implementation, there would be minor adverse effects of temporary duration at

project sites to water quality. After project implementation, there would be minor beneficial

effects of long term duration in the project area to water quality.

1. Stream bank conditions at trail stream crossings:

During the construction of the perennial stream fords and during the stream bank rehabilitation

work, the trail crew would be working in the stream channels. These activities would disturb fine

sediments in the channel and adjacent stream banks. The result would be minor turbidity in the

stream, which would persist for up to day after work in the stream is completed. Sediment from

project activities would be transported downstream up to 150 feet, and the turbidity may be


detectable up to 1,000 feet downstream during days there is in-stream activities. The project

activities at intermittent stream crossings would typically include the installation of a single row

of rock tread retainers at the crossings. Because the scale of work is much smaller and of shorter

duration than at perennial crossings, the adverse effects to water quality during construction

would be correspondingly lower. When possible (years with average or below average

precipitation), work at intermittent crossing would be conducted while the streams are not

carrying water.

After project implementation, stream banks would be stabilized at ten perennial and nine

intermittent stream crossing. An average of .08 acre of currently disturbed area of stream banks

at each crossing would be stabilized, with an estimated 85% decrease in the amount of sediment

entering stream channels. Over the long term, vegetation in riparian area adjacent to trail stream

crossings would recover and increase stream shade cover at crossings.

2. Trail sections susceptible to erosion:

During construction of trail stabilizing structures, there would be temporary periods when

disturbed soils could be eroded by sudden storm events. Trail stabilizing structures would be

installed on 100-200 foot sections of trail at one time, so the length of trail susceptible to erosion

would be confined to these short sections undergoing treatment. Best Management Practices

(BMP) 2-2 and 2-3 would minimize the risks of erosion. Any erosion would be localized and

temporary in duration.

After project implementation, soil erosion from the trail tread would be reduced compared to the

existing condition, and the trail structures would prevent sediment from reaching streams. No

trail sections with steeper grades would lack erosion control structures. In addition, the

abandoned section of Hilton Lakes trail 3,000 feet in length would be stabilized.

3. Hydrologic connectivity of streams and meadows:

Measure a - Proportion of causeways in watershed maintaining connectivity: There would be

minor adverse effects of short term duration (two to three weeks) from sedimentation and

turbidity while causeway stringers are replaced. After completion of the project, the four

sections of causeway totaling 1,050 feet in length (100% of causeways in project area) would

maintain connectivity by allowing surface and subsurface water to flow past the trail.

Measure b - Proportion of trail in project area in meadows: Approximately 250 feet of the Hilton

Creek Trail (.4% of all trails in watershed) would be re-routed from its current meadow location

to drier upland soils. The meadow proposed for the treatment was rated functional-at-risk in

2005, so there would be relatively greater benefits to this re-route, including moving the trail

away from the stream bank, which is the source of the risk for meadow degradation.

Approximately 600 feet of this trail would continue to be aligned through seasonally wet

meadows. These sections of trail in meadows would continue to have compacted soils in the

trail tread which could channel surface water flows down the trail and have the potential to create


head cuts. The Forest is not proposing to realign these sections because there is no practical

alternative alignment for the trail in these meadows. They would be reconstructed in place and

existing head cuts would be treated (Measure d) to protect the hydrologic connectivity of streams

and meadows in this portion of the project area. Approximately 1,000 feet of the Hilton Lake #2

Spur Trail is aligned through a seasonally wet meadow adjacent to Davis Lake. The Forest is

not proposing to realign these sections because there is no practical alternative alignment for the

trail in these meadows.

Measure c - Proportion of stream crossings with intercepted flow: Connectivity of three

intermittent streams to the watershed would be reestablished. None of the twenty stream

crossings along the Hilton Lakes Trail would intercept stream flows.

Measure d - Number of head cuts that are associated with trails: The three head cuts adjacent to

the Hilton Creek Trail would be treated to minimize the risk of eroding and contributing

sediment to streams. During work on the head cut treatments, there would be minor turbidity in

the stream, which would persist for up to a day after work in the stream is completed. Sediment

from project activities would be transported downstream up to 150 feet, and the turbidity may be

detectable up to 1,000 feet downstream during days there is in-stream activities. After

completions of the treatments, there would likely be no further erosion at these sites.

3.2.4 Cumulative Effects of the Proposed Action on Water Quality

There would be no cumulative effects because there are no other existing environmental

conditions, ongoing projects, or reasonably foreseeable projects with effects to water quality that

would overlap in space and time with the direct and indirect effects of the Proposed Action.

3.3 Effects to Soils: No Action and Proposed Action

The effects to soils will be discussed through the indicator and measure associated with the

fourth project objective.

Indicator: vegetation and soils disturbance outside the trail corridor: The measure of

disturbance is the proportion of trail in the project area that exceeds the design guidelines for trail

width.

The analysis boundary for direct and indirect effects to soils is the area within over-widened trail

sections (see sections labeled “reduce trail width” in Figures 3-5).

3.3.1 Direct and Indirect Effects of No Action on Soils

There would be minor adverse effects of long term duration along over-widened trail sections. In

the project area, there are currently 9,750 feet of trail (17%) that exceed design guidelines, and

have disturbed soils and vegetation. The over-widened trail sections are primarily in dry upland

areas with granitic soils and widely spaced trees. There would continue to be a downward trend

in vegetation and soils conditions along trail corridors that are currently over-widened. The

downward trend has been caused by visitors traveling off the established trail tread, and this use


is expected to continue. The interdisciplinary team documented the areas with disturbed soils

through its problem assessment approach during site visits. Site observations are consistent with

research into trampling disturbance of soils by visitors summarized by Monz CA and others

(2010). Monz concluded that trampled vegetation and disturbed soils along trails lead to

compacted soils, reduced soil productivity, and increase the likelihood of erosion.

3.3.3 Cumulative Effects of No Action on Soils


conditions, ongoing projects, or reasonably foreseeable projects with effects to soils that would

overlap in space and time the direct and indirect effects of the No Action Alternative.

3.3.3 Direct and Indirect Effects of the Proposed Action on Soils

There would be minor beneficial effects of long term duration along currently over-widened trail

sections. The implementation prescriptions would minimize off-trail trampling along 6,750 feet

of currently over-widened trail. The prescription would allow vegetation to become re-

established. As vegetation becomes reestablished on the over-widened trail sections, soils would

stabilize and become less prone to erosion. An additional 3,000 feet of the existing Hilton Lakes

Trail that is over-widened would be abandoned and rehabilitated (site18). Without any further

visitor use, soil conditions on the rehabilitated section of trail are expected to stabilize and

ground vegetation reestablish in the medium term.

3.3.4 Cumulative Effects of the Proposed Action on Soils


conditions, ongoing projects, or reasonably foreseeable projects with effects to soils that would

overlap in space and time the direct and indirect effects of the Proposed Action.

3.4 Effects to Wilderness Character: No Action and Proposed Action

Effects to wilderness character will be discussed in term of the four qualities of wilderness

character: natural; untrammeled; undeveloped; and opportunities for solitude or a primitive and

unconfined type of recreation. For each quality, indicators and measures applicable to this trails

project have been selected. The indicators and measures will be used to compare the effects of

the No Project alternative and the Proposed Project on the four qualities of wilderness character.

Natural Quality

This quality addresses both the intended and unintended effects of human actions on ecological

systems inside wilderness. Trail conditions may affect the local watershed conditions by

diverting water from natural channels, displacing soil, contributing sediment to surface water,

and lowering groundwater tables. Local watershed conditions are part of the hydrologic system,

which is an ecological system within wilderness. This analysis will utilize the three indicators,

measures, and analysis area from the Effects to Water Quality Section 3.2 to discuss the effects


on the natural quality of wilderness. The indicators are: stream bank conditions at stream

crossings; trail tread sections that are susceptible to erosion; and the hydrologic connectivity of

streams and meadows.

Untrammeled Quality

The proposed project does not include any actions that would manipulate the biophysical

environment. Since there would not be any actions that manipulate the biophysical environment,

there would be no effects to the untrammeled quality, and this quality will not be discussed

further in this analysis.

Undeveloped Quality

This quality addresses the presence of structures, construction, habitations, and other evidence of

modern human presence or occupation that are not related to recreation in wilderness. The

proposed project does not include any actions that would develop non-recreational facilities in

wilderness. Since the proposed project does not include the development of any non-recreation

facilities, there would be no effect on this character of wilderness quality, and this quality will

not be discussed further in this analysis.

Opportunities for Solitude or Primitive and Unconfined Recreation

This quality addresses conditions that affect the opportunity for people to experience solitude or

a primitive and unconfined type of recreation in a wilderness setting.

Indicator -Trail crew presence in wilderness: The measure of trail crew presence is the

number of days of trail crew operations in the project area. The presence of a trail crew working

on the trails may affect visitors’ solitude, because the crew personnel would represent an

increase over the typical number of visitors to the Hilton Analysis Unit.

The analysis area for the opportunities for solitude is the Hilton Analysis Unit. Analysis Units

are areas within the John Muir Wilderness with similar resource conditions and recreation

settings, and provides the appropriate area for assessing effects on these qualities of wilderness

character. The analysis unit as the basis for the context of effects was developed for the

environmental analysis of the 2005 Trail and Commercial Pack Stock Management in the Ansel

Adams and John Muir Wildernesses Final Environmental Impact Statement.

Indicator: Facilities that decrease self-reliant recreation: The measure for this indicator is

facilities that decrease self-reliant recreation such as trail structures designed to make travel

easier. Trail structures, especially bridges, in wilderness are considered to have an adverse effect

on this quality because they reduce the challenge of travel, especially stream crossings, in

wilderness.

The analysis area for opportunities for a primitive and unconfined type of recreation is the Hilton

Analysis Unit.


3.4.1 Direct and Indirect Effects of No Action on Wilderness Character

Natural quality

There would be a minor adverse effect of long term duration in the project area to water quality

for the same reasons discussed in the Effects on Water Quality Section 3.2.1 above. If the No

Action Alternative is selected, there would be a downward trend in three water quality

indicators: stream bank conditions at stream crossings; trail tread sections that are susceptible to

erosion; and the hydrologic connectivity of streams and meadows. The downward trends would

be a minor adverse effect on local watershed conditions. Watershed conditions are a component

of the hydrologic system, which is one of the ecological systems comprising the natural quality

of wilderness character.

Opportunities for solitude or primitive and unconfined type of recreation

There would be no effects on either the opportunities for solitude or opportunities for primitive

and unconfined recreation because there would be neither any trail crews nor additional trail

facilities under the No Action Alternative. Routine trail maintenance work would, however,

continue on a regular basis under the No Action Alternative. Trail crews comprised of four or

five people would camp and maintain trails in the project area for one to two weeks every third

year. The sight and sound of these trail crews may affect some visitors’ perception of solitude.

3.4.2 Cumulative Effects of No Action on Wilderness Character

There would be no cumulative effects to wilderness character because there are no other existing

environmental conditions, ongoing projects, or reasonably foreseeable projects with effects to the

natural quality, opportunities for solitude, or opportunities for a primitive and unconfined type of

recreation that would overlap in space and time with the direct and indirect effects of the No

Action Alternative.

3.4.3 Direct and Indirect Effects of the Proposed Action on Wilderness Character

Natural Quality

During project implementation, there would be minor adverse effects of temporary duration at

project sites to water quality. There would be minor adverse effects to the natural quality of

wilderness character because water quality is an indicator of watershed conditions. Watershed

conditions in turn are a component of the hydrologic system, which is one of the ecological

systems comprising the natural quality of wilderness character.

After project implementation, there would be minor beneficial effects of long term duration in

the project area to water quality. The rationale for these effects is the same as that discussed in

the Effects on Water Quality Section 3.2.3 above. There would be minor beneficial effects to the

natural quality of wilderness character because water quality is an indicator or watershed


conditions. Watershed conditions in turn are a component of the hydrologic system, which is

one of the ecological systems comprising the natural quality of wilderness character.

Opportunities for solitude or primitive and unconfined type of recreation

There would be minor adverse effects of short term duration in the Hilton Analysis Unit to the

opportunities for solitude. The Forest Service estimates that the Proposed Action would be

implemented over the course of three summer seasons. Although the duration of work each year

would depend on available funding, each summer a trail crew (approximately 5-8 members)

would likely be working and camping within the Hilton Lakes Basin from early July to mid-

September. Trail crews would work at several smaller project sites such as the intermittent

stream crossings simultaneously. At the relatively larger project sites (perennial stream

crossings and trail stabilization sections), the entire crew would work on one project site.

Visitors may see and hear a trail crew while traveling along the trail corridors. Solitude at

campsites near the Davis Lake outlet, Lake 3 outlet and Lake 4 outlet would also be affected if

visitors were staying at a campsite when project work occurs nearby. Because trail crews would

not camp at the locations in the lakes basin that are the typical destinations for visitors, their

camp would not be within sight or sound of other visitors. This means that the trail crew camps

are not expected to affect opportunities for solitude.

There would be negligible effects in the Hilton Analysis Unit to the opportunities for a primitive

and unconfined type of recreation. A log stock bridge, which would make travel marginally

easier for both hikers and stock users, would be installed on one of the perennial stream

crossings along the Hilton Lakes Trail (site #7). The current crossing over this minor stream has

stepping stones that allow hikers to keep their feet dry. The change in type of crossing from

stepping stones to foot bridge would be a negligible change in the ease of the crossing for hikers.

Eight of ten perennial stream crossings in the project area would remain stream fords. Since the

addition of the footbridge is confined to one crossing over a minor stream that currently has

stepping stones for hikers, it would be a negligible effect to this quality.

3.4.4 Cumulative Effects of the Proposed Action on Wilderness Character

There would be no cumulative effects to wilderness character because there are no other existing

environmental conditions, ongoing projects, or reasonably foreseeable projects with effects to the

natural quality, opportunities for solitude, or opportunities for a primitive and unconfined type of

recreation that would overlap in space and time the direct and indirect effects of the Proposed

Action.


3.5 Effects Relative to Significance Factors

1. Beneficial/adverse impacts.

The beneficial and adverse effects of the No Action and Proposed Action can be found in the

following Sections of the Environmental Analysis: Section 3. 2, Effects to Water Quality;

Section 3.3, Effects to Soils; and Section 3.4, Effects to Wilderness Character.

2. The degree to which the proposed action affects public health or safety.

Although the purpose of the project is to protect watershed conditions, one element of the

Proposed Action, the replacement of the wooden bridge at site 29, would also protect public

safety. The bridge stringers are decaying, and a failed bridge structure would affect public’s

ability to safely travel on that section of trail.

A second activity of the Proposed Action, the installation of trail stabilizing structures, would

primarily be undertaken to protect water quality. Stabilizing structures on currently degraded

sections of trail tread would make some sections of the trail safer to travel over because the

irregular surface of the degraded sections would be more stable.

There are no other foreseeable projects in the project area that would affect public safety, so

there would be no cumulative effects on public safety.

3. Unique characteristics of the geographic area such as proximity to historic or cultural resources, parklands, prime farmlands, wetlands, wild and scenic rivers, or ecologically critical areas.

Historic or cultural resources: Cultural Resources Report No. 2011-05-04-01686 has been

prepared by the Forest Archeologist. The Report’s Finding of Effect concluded there would be

no direct, indirect, or cumulative effects on historic or cultural resources. With implementation

of the standard protection measures and/or completion of this report, mandatory historic

preservation requirements for this undertaking have been met according to the Programmatic

Agreement among The U.S.D.A Forest Service, Pacific Southwest Region, California State

Historic Preservation Officer, and Advisory Council on Historic Preservation regarding the

identification, evaluation and treatment of historic properties managed by the National Forests of

the Sierra Nevada, California.

Parklands: There are no parklands in the project area, therefore there would be no direct,

indirect, or cumulative effects on parklands.

Prime farmlands: There are no prime farmlands in the project area, therefore there would be no

direct, indirect, or cumulative effects on prime farmlands.

Wetlands: During project implementation activities to reconstruct an existing causeway and log

bridge, the Proposed Action would have minor adverse effects of temporary duration to a wet

meadow (project site 29, meadow hil8). Project activities would likely create localized turbidity


in the stream through the meadow at the bridge site. After project completion, the Proposed

Action would have minor beneficial effects of long term duration in the project area.

The Proposed Action is in compliance with Executive Orders 11988 and 11990 because the

project would not destroy or modify floodplains and wetlands. The interdisciplinary team

concluded there is no feasible alternative to the Hilton Creek Trail’s current alignment through

meadow hil8. Trail features would be reconstructed in place and existing head cuts would be

treated to protect the hydrologic connectivity of streams and meadows in this portion of the

project area. The Forest would implement three Best Management Practices described in Section

2.2.2 to protect wetlands during project implementation. Practice 7-3, Protection of Wetlands,

would minimize effects during reconstruction of the causeway.

The No Action Alternative would not include any activities in floodplains or wetlands.

Wild and Scenic Rivers: There are no Wild and Scenic Rivers in the project area, therefore

there would be no direct, indirect, or cumulative effects on Wild and Scenic Rivers.

Wilderness: The effects to Wilderness Character from the No Action and Proposed Action are

described in Section 3.4.

Ecologically critical areas: There are no ecologically critical areas identified by the Forest

Service in the project area, therefore there would be no direct, indirect, or cumulative effects on

ecologically critical areas.

4. The degree to which the effects on the human environment are likely to be highly

controversial.

No issues or controversy about the Proposed Action were brought forward by the public during

scoping or by Native American Tribes in response to official letters sent to tribal governments.

The implementation of the trail stream crossings and other project elements will utilize routine

construction techniques suitable for trails in wilderness. There is no known controversy about

the anticipated effects.

5. The degree to which the possible effects on the human environment are highly uncertain

or involve unique or unknown risks.

The Inyo National Forest has completed four similar trail projects on the White Mountain Ranger

District with similar resource conditions in the past ten years. All four projects met the projected

improvements to resource conditions, and none had any unanticipated effects to wilderness

character or other elements of the human environment.


6. The degree to which the action may establish a precedent for future actions with

significant effects or represent a decision in principle about a future consideration.

The Inyo National Forest is disclosing in this Environmental Assessment the complete set of

proposed trail management actions for the project area. The Proposed Action includes all trail-

related activities that the Forest can foresee in the Hilton Analysis Unit. The environmental

analysis concludes there would be no significant effects resulting from the complete list of

identified trail actions in the project area. This is a site-specific project that does not set

precedence for future decisions with significant effects or present a decision in principle about

future considerations. If the need for additional trail actions in the Hilton Analysis Unit is

identified in the future, a separate site-specific environmental analysis would be completed prior

to proceeding with those actions.

7. Whether the action is related to other actions with individually insignificant but

cumulatively significant impacts.

The discussion of cumulative effects in Section 3.1.2 indicates the Proposed Action does not

overlap in time and space with other Forest Actions that would have similar effects in the project

area. Therefore there would not be any cumulatively significant impacts.

8. The degree to which the action may adversely affect districts, sites, highways, structures,

or objects listed in or eligible for listing in the national Register of Historic Places, or may

cause loss or destruction of significant scientific, cultural, or historic resources.

The Forest Archeologist prepared a Cultural Resources Report, dated December 1, 2011 and

incorporated by reference, pursuant to the Programmatic Agreement among the U.S.D.A Forest

Service, Pacific Southwest Region, California State Historic Preservation Officer, and Advisory

Council on Historic Preservation regarding the identification, evaluation and treatment of historic

properties managed by the national forests of the Sierra Nevada, California. The Forest

Archeologist found there would be no adverse effects to districts, sites, highways, structures, or

objectives listed in or eligible for listing in the National Register of Historic Places from the

Proposed Action.

9. The degree to which to action may adversely affect an endangered or threatened species

or its habitat that has been determined to be critical under the Endangered Species Act of

1973.

The Forest Service has complied with the Endangered Species Act requirements by completing:

1) a Biological Evaluation for Threatened, Endangered, Proposed, and Sensitive Plants for the

project; 2) a Terrestrial and Aquatic Wildlife Biological Evaluation/Assessment.

The Biological Evaluation for Threatened, Endangered, Proposed, and Sensitive Plants, dated

December 7, 2011 and incorporated by reference, has been prepared by the Forest Botanist. The


evaluation concluded there is no potential habitat for any threatened, endangered, or proposed

plant species within or adjacent to the proposed project area. The proposed project area may

provide potential habitat for sensitive Botrychium species and two Forest Service sensitive

species, Epilobium howellii and Helodium blandowii. The Botanist’s determination is that due to

the lack of any sensitive Botrychium species in the project area, there would be no impact to

these species. The proposed project may impact individual Epilobium howellii and Helodium

blandowii plants, but is not likely to lead to a trend toward federal listing or loss of viability.

The Biological Evaluation/Assessment for Terrestrial and Aquatic Wildlife, dated December 2,

2011 and incorporated by reference, has been prepared by the Forest Wildlife and Forest

Fisheries Biologists. Through their evaluation, they made the determination that the Proposed

Action may impact individuals, but would not lead toward federal listing or loss of viability for

the following species: northern goshawks; bald eagles; American marten; Sierra Nevada red fox;

and wolverine. There would be no effect to Threatened, Endangered, Proposed, and Sensitive

aquatic species because there is no habitat for Threatened, Endangered, Proposed, and Sensitive

aquatic species in the project area.

10. Whether the action threatens a violation of Federal, State, or local law or other

requirements imposed for the protection of the environment.

Wilderness Act: The Proposed Action is consistent with the Wilderness Act Section 4(d)

because the project protects and preserves wilderness character while providing for use and

enjoyment of the area by visitors. Section 3.4.3 of the environmental assessment concludes the

Proposed Action would have a minor long term beneficial effect to the natural quality of

wilderness character, a minor short term adverse effect on the opportunities for solitude during

project implementation, and a negligible effect on the opportunities for a primitive and

unconfined typed of recreation.

Clean Water Act: The Proposed Action is consistent with the Clean Water Act through the

inclusion of Best Management Practices in the project design. The Forest Service has developed

Best Management Practice guidelines to prevent water degradation on National Forest lands as

part of the Management Agency Agreement between the Forest Service and the State Water

Resources Control Board. The Forest has included four Best Management Practices in the

Proposed Action Section 2.2.2 to protect water quality. The Forest Service will also obtain a

Section 401 water quality certification from the California Regional Water Quality Control

Board for potential streambed alteration and/or discharge of fill material to surface water

associated with the Proposed Action.

National Forest Management Act: The Proposed Action is consistent with the National Forest

Management Act, because neither alternative would threaten the viability of any sensitive

species (Murphy and Sims 2011 and Weis 2011).

Sierra Nevada Management Indicator Species Amendment Record of Decision (2007): A

Management Indicator Species Report, dated December 2, 2011 and incorporated by reference,


has been prepared by Forest Wildlife and Fisheries Biologists (Murphy, Ettema, Sims 2011).

The effects of the Proposed Action on the habitat of two management indicator species were

evaluated:

Riverine habitat: There would be temporary adverse effects to riverine habitat from increased

sedimentation in streams at project sites during the Proposed Action’s implementation. There

would be, however, long term benefits to riverine habitat in the project area by reducing trail-

related sediment in streams and increasing water surface shade. The Proposed Project would not

alter existing trends in habitat or macro invertebrates across the Sierra Nevada bioregion.

Snags in green forest ecosystem: The Proposed Action would remove snags in a green forest

ecosystem. The removal would, however, stay within the Sierra Nevada Forest Plan Amendment

standard of three snags per acre. The Proposed Action would not alter the existing trend in this

ecosystem component, nor will it lead to a change in the distribution of hairy woodpecker across

the Sierra Nevada bioregion.

Inyo National Forest Land and Resource Management Plan (1988) (LRMP): The Proposed

Project is consistent with the watershed goals established in the LRMP: project activities would

be conducted to maintain or improve soil productivity, to maintain favorable conditions of water

flow, and to comply with state and federal water quality goals. The Proposed Action is

consistent with the wilderness goal for the LRMP: project activities would protect wilderness

character, provide opportunities for primitive recreation, maintain watershed values, and enhance

the quality of wilderness experiences (LRMP, pg 69).

Sierra Nevada Forest Plan Amendment Record of Decision (2004): The Hydrology and Soils

Specialist Report, dated December 2011 and incorporated by reference, indicates the Proposed

Project is consistent with the Riparian Conservation Objectives, standards and guidelines

applicable to this project.

The Forest has complied with the 2004 Record of Decision direction regarding the involvement

of American Indian Tribes by soliciting the Tribes’ opinions and concerns related to the

Proposed Action.

Record of Decision for Management Direction for the Ansel Adams, John Muir, and

Dinkey Lakes Wildernesses (2001): The Wilderness Specialists Report, dated December 19,

2011 and incorporated by reference, indicates the Proposed Action is consistent with the Trails

direction contained in the Ansel Adams, John Muir, and Dinkey Lakes Wilderness Management

Plan. The Proposed Action is also consistent with Forest Service Manual Section 2323 policies

for Forest System trails in wilderness, and Forest Service Handbook Section 2309.18 guidelines

for trail project planning.


Chapter 4 List of Persons Consulted

4.1 Environmental Assessment Preparers

Nicholas Ettema, Fisheries Biologist

Carmen John, Recreation Special Use Administrator

Susan Joyce, NEPA Coordinator & Forest Planner

Leeann Murphy, Wildlife Biologist

Colleen Nicholas, South Zone Archeologist

Jeff Novak, Wilderness Manager & Project Leader

Casey Shannon, Hydrologist

Lisa Sims, Fisheries Biologist

Keith Waterfall, Wilderness Manager

Sue Weiss, Botanist

4.2 References cited

Marion and Leung. 2001. Trail Resource Impacts and An Examination of Alternative

Assessment Techniques. Journal of Park and Recreation Administration, volume 19, number 3,

pp. 26.

Monz CA and others. Sustaining Visitor Use in Protected Areas: Future Opportunities in

Recreation Ecology Research Based on the USA Experience. Environmental Management

(2010) pg 554.

Murphy, Sims. 2011. Terrestrial and Aquatic Wildlife Biological Evaluation/Assessment, Hilton

Lakes and Hilton Creek Trail Project, December 2, 2011. USDA, US Forest Service, Inyo

National Forest

Murphy, Ettema, Sims. 2011. Management Indicator Species Report, Hilton Lakes and Hilton

Creek Trail Project, December 2, 2011. USDA, US Forest Service, Inyo National Forest.

Nicholas. 2011. Cultural Resources Report, Hilton Lakes and Hilton Creek Trail Project,

December 1, 2011. USDA, US Forest Service, Inyo National Forest.

Novak. 2011. Wilderness Specialist Report, Hilton Lakes and Hilton Creek Trail Project,

December 19, 2011. USDA, US Forest Service, Inyo National Forest.

Olive and Marion. 2008. The influence of use-related, environmental, and managerial factors on

soil loss from recreational trails. Journal of Environmental Management, volume 90, pp. 1483-

1493.

Shannon. 2011. Hydrology and Soils Specialist Report, Hilton Lakes and Hilton Creek Trail

Project, December 2011. USDA, US Forest Service, Inyo National Forest.

USDA Forest Service. 1988. Inyo National Forest Land and Resource Management Plan.


USDA Forest Service. 2001. Record of Decision, Ansel Adams, John Muir and Dinkey Lakes

Wilderness Management Plan, Final Environmental Impact Report.

USDA Forest Service. 2004. Record of Decision, Sierra Nevada Framework Plan Amendment,

Final Environmental Impact Statement.

USDA Forest Service. 2005. Trail and Commercial Pack Stock Management in the Ansel Adams

and John Muir Wildernesses, Final Environmental Impact Report.

Weis. 2011. Biological Evaluation for Threatened, Endangered, Proposed, and Sensitive Plants,

Hilton Lakes and Hilton Creek Trail Project, December 7, 2011. USDA, US Forest Service.


Chapter 5 Appendices

Appendix A: Description of Trail Prescriptions

Head cut stabilization prescription

Stabilize with rock and coco-fiber filter cloth (rock chutes). Slope back head cuts to 30 degree

angle, lay filter cloth, then build rock armor chute to protect bare soil and arrest head cut

migration. Replant where practical any vegetation removed from slope.

Intermittent stream crossing prescription

Reduce where needed the trail width at stream crossings to Trail Class 3 design standards with

rock (see Forest Service Handbook Section 2309.18, Chapter 14.2). Install single course of

retaining rocks on stream bank to maintain stream channel width and prevent the trail from

capturing the stream flow. If necessary, armor stream outlet below trail crossing with rock

sufficient to prevent stream down cutting at the crossing. Rock sources would be within 75 feet

on either side of trail.

Over-widened trail prescription

Place rock or large logs to delineate trail at design standard width. Naturalize over-widened

areas with locally obtained duff, loose woody debris and rock. Add trail grade stabilizing

structures (rock checks or rock water bars) where trail tread is eroding or grade exceeds fifteen

percent. Rock and wood sources would be within 75 feet on either side of trail.

Perennial stream crossing prescription

Rebuild trail entries to stream to match as nearly as practical the reference stream bank’s width

and slope. Construct rock and fill entry steps to crossing suitable for use by pack stock. Stabilize

over-widened stream banks with rock or logs, and restore stream channel width to match

conditions of the stream channel unaffected by the trail (upstream or downstream). Rock sources

would be within 150 feet on either side of trail

Reconstruct log causeway prescription

Replace existing decaying log retainers on causeway with logs up to 18 inches in diameter

obtained from locally felled lodge pole trees. Add new rock crush fill. Trees and rock may be

obtained up to 300 feet on each side of the trail corridor

Rehabilitate abandoned trail section prescription

Naturalize over-widened areas with locally obtained (within 150 feet of trail) duff, loose woody

debris and rock. Add water bars in areas where trail tread had been eroding.

Trail stabilization prescription

Locate trail stabilizing and drainage structures where trail tread is eroding or grade exceeds

fifteen percent. The size and placement of structures is primarily to protect trail tread from

erosion caused by water flow on trail. Trail stabilizing and drainage structures include rock

steps, rock checks, and water bars. Rock sources would be within 75 feet on either side of trail.


Appendix B: Project Site Prescriptions

Hilton Lakes Trail 1. Trail crosses an intermittent stream. Employ the intermittent stream crossing prescription

□ Existing condition: lack of rock retainers to prevent trail tread erosion; trail width at

crossing exceeds design guidelines.

2. Trail section 300 feet in length. Employ the reduce trail width prescription.

□ Existing condition: Trail is over-widened, with multiple trailing through dry upland soils.

3. Trail crosses a perennial stream. Employ the perennial stream crossing prescription, and

improve drainage function of the existing causeway.

□ Existing condition: trail causeway is intercepting stream flow, with standing water on

trail.


□ Existing condition: Trail is over-widened, with multiple trailing through dry upland soils.

5. Trail crosses a perennial tributary to Rock Creek. Employ the perennial stream crossing

prescription.

□ Existing condition: lack of rock retainers to prevent trail tread erosion; stream channel is

over-widened.

6. Trail crosses an ephemeral stream. Employ the intermittent stream crossing prescription.

□ Existing condition: a wet and muddy section of trail in early summer.

7. Trail crosses a perennial tributary to Rock Creek. Construct 100 foot re-route on each side of

creek and new stream crossing with wooden deck bridge designed for pack stock use.

Employ the perennial stream crossing stabilization prescription and rehabilitate abandoned

section of trail and streambanks.

□ Existing condition: stream channel is over-widened, with multiple crossing points.


□ Existing condition: trail is over-widened.

9. Trail crosses an intermittent stream. Employ the intermittent stream crossing prescription.







□ Existing condition: trail is over-widened, with multiple trailing through dry upland soils.

12. Trail crosses an ephemeral stream. Employ the intermittent stream crossing prescription.





□ Existing condition: lack of rock retainers to prevent trail tread erosion; trail intercepts

flow from a spring.

14. Trail crosses an intermittent stream. Employ the intermittent stream crossing prescription

□ Existing condition: lack of rock retainers to prevent trail tread erosion; trail intercepts

flow from a spring.

15. Trail section 400 feet in length. Employ both the trail stabilization and reduce trail width

prescription.

□ Existing condition: trail section is steep, over-widened, and susceptible to erosion.

16. Hilton Lakes Trail re-route. Construct re-route of Hilton Lakes Trail with Trail Class 3

design on the current alignment of the Hilton Cut-off Trail. Length of re-route is

approximately 4,000 feet. Install rock checks or grade stabilizing structures in four locations,

totaling approximately 300 feet in length.

17. Trail crosses a perennial tributary to Rock Creek. Employ the perennial stream crossing

prescription to construct a stream crossing that is designed for use by pack stock.

18. Abandon a section of Hilton Lakes Trail 3,000 feet in length. Stabilize and rehabilitate

abandoned section.

□ Existing condition: majority of this section is over-widened, with braided trail tread and

disturbed soils up to 50 feet wide.

19. Trail crosses a perennial tributary to Rock Creek. This site is within the section of Hilton

Lakes Trail that will be abandoned. Stabilize and rehabilitate stream banks of perennial

stream.

□ Existing condition: stream channel is over-widened, with eroding stream banks.

20. Trail section 2,700 feet in length. Employ the reduce trail width prescription, and increase the

sinuosity of the trail on steeper slopes.

□ Existing condition: Trail section is over-widened with multiple trailing.

21. Trail section 400 feet in length. Employ the trail stabilization prescription

□ Existing condition: trail section is steep and eroding due to the lack of trail structures.

22. Trail section 800 feet in length. Reconstruct deteriorating rock checks and steps; add several

additional checks and steps at lower end of this section to reduce the height of existing steps.


□ Existing condition: the rock fill used in a series of rock checks and steps has eroded from

trail.

End of Hilton Lakes Trail project sites

Hilton Creek Trail

23. Section of trail 1,700 feet in length. Reduce trail width to one track. Rehabilitate abandoned

track and install drainage structures.

□ Existing condition: trail section has a dual track (it is a remnant of a mine road).

24. Section of trail 1,200 feet in length. Reduce trail width to one track. Rehabilitate abandoned

track and install drainage structures.

□ Existing condition: trail section has a dual track (it is a remnant of a mine road).

25. Trail crosses a perennial Hilton Creek. Employ the perennial stream crossing prescription.

Rebuild and stabilize eroded stream banks on both entries to match natural stream bank

alignment. Build rock and fill check entry steps to the crossing.

□ Existing condition: stream channel is over-widened, with scoured stream banks.

26. Section of trail 700 feet in length. Decommission and rehabilitate the western trail in the

multiple trailing section. Employ the trail stabilization prescription on the eastern section of

trail.

□ Existing condition: The north end of the section has 200 feet of trail with multiple

trailing. South of the multiple trailing section, the trail steepens and is incised for 500

feet in length.

27. Section of trail 1,800 feet in length. Employ trail stabilization prescription

□ Existing condition: trail section is steep and incised.

28. Section of trail 300 feet in length. Employ trail stabilization prescription

□ Existing condition: trail section is steep and eroding.

29. Two log and rock fill causeways across wetland area totaling 500 feet in length. Reconstruct

the existing two log causeways with rock fill. Reconstruct existing bridge over small

perennial stream constructed of log stringers with plank deck over meadow (meadow id hil8).

Stabilize two head cuts in stream channel immediately upstream of bridge crossing.

□ Existing condition: 1) causeway log retainers are deteriorating due to age, and rock fill

has been lost from the causeway tread; 2) the log stringers for the bridge have decayed.

30. Section of trail 200 feet in length. Employ trail stabilization prescription to improve water

drainage from trail.

□ Existing condition: seasonally wet from overland flow during spring snowmelt.

31. Use trail crosses to campsites on north side of Davis Lake outlet from Davis Lake. Employ

the perennial stream crossing prescription. Rebuild and stabilize eroded stream banks on

both entries to match natural stream bank alignment.


□ Existing condition: stream banks are scoured at trail entries to crossing.



□ Existing condition: water is channeled down the middle of the trail during spring

snowmelt.



□ Existing conditions: Seasonally wet section of trail.

34. Trail crosses an intermittent stream. Employ the intermittent stream crossing prescription



35. Three log and rock fill causeways totaling 540 feet in length. Reconstruct the three

causeways with rock fill.

□ Existing condition: causeway log retainers are deteriorating due to age, and rock fill has

been lost from the causeway tread.

36. Section of trail approximately100 feet in length. Employ trail stabilization prescription and

also reduce trail width.

□ Existing condition: Trail section with wet soils.


Employ the trail stabilization prescription on 50 feet of trail on the north side of the stream

crossing.

□ Existing condition: lack of rock retainers to prevent trail tread erosion; trail on north side

of crossing has eroding tread.

38. Section of trail 1,000 feet in length. Employ trail stabilization prescription.

□ Existing condition: Portions of this steep section of trail are entrenched and, due to the

lack of trail stabilizing structures, continue to erode.

39. Trail crosses a perennial stream at outlet from Lake Three. Employ the perennial stream

crossing prescription and construct rock causeway 50 feet in length on west side of crossing

to protect wet soils.

□ Existing condition: stream banks are over-widened; the trail has two entries to the

crossing on the east side of the stream; the trail is over-widened on the west side of the

crossing, which contains wet soils.

40. Section of trail 300 feet in length. Employ trail stabilization prescription. Use Trail Class 2

design guidelines.

□ Existing conditions: the trail tread is eroding on a steep section of trail.

41. Trail crosses the perennial Hilton Creek. Employ the perennial stream crossing prescription.

Re-route 100 feet of trail east of Hilton Creek from existing alignment through a meadow to


an alignment on upland soils. Use Trail Class 2 design guidelines. Rehabilitate abandoned

section of trail. Construct rock causeway 75 feet in length on west side of creek to protect

meadow adjacent to creek. Maintain existing hiker bridge across the creek.

□ Existing condition: trail crosses a meadow at the eastern approach to the crossing; stream

banks are over-widened, with several entry points to the crossing; the trail is incised on

the western approach to the crossing, which is on wet meadow soils.

42. Re-route 150 feet of trail to an alignment on upland soils. Stabilize head cut on upslope side

of existing trail through the meadow. Employ the intermittent stream crossing prescription

where flow from small seep crosses the trail west of re-route. Use Trail Class 2 design

guidelines for the re-route.

□ Existing condition: the trail alignment west of Hilton Creek is in a riparian area along the

stream bank.


design guidelines.

□ Existing condition: a steep section of trail that lacks trail stabilizing structures.

44. Trail crosses a perennial stream at outlet from Lake Four. Employ the perennial stream

crossing prescription. Construct rock causeway seventy five feet in length on east side of

crossing to protect wet soils. Construct entry to crossing on west side of creek with rock

checks and steps.

□ Existing condition: Trail crosses wet soils at eastern approach to crossing; there is an

abrupt stream bank on western site of the crossing.

End of Hilton Creek Trail project sites



design guidelines.

□ Existing conditions: Trail descends steep embankment that lacks any stabilization

structures.

46. Trail crosses perennial Hilton Creek at inlet to Davis Lake. Employ the perennial stream

crossing prescription. Construct entry to crossing on east side of creek with rock checks and

rock fill retaining structures. Construct entry to crossing on west side of creek with rock

checks and steps.

□ Existing conditions: entry to crossing on the east side is steep, which stock riders are

attempting to ride around; entry to crossing on the west side is on a steep embankment,

which is scoured.

47. Section of trail 200 feet in length. Close and rehabilitate trail braids up steep embankment.

Remove fallen trees from existing trail alignment.

□ Existing condition: Trail has become braided immediately west of the crossing at inlet to

Davis Lake.

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