Project Background

Yosemite Valley is the most popular destination in Yosemite National Park (figure I-1). As a result of the pressure on Valley resources from several million visitors annually, the National Park Service completed the Yosemite Valley Plan (NPS 2000a) to manage natural and cultural resources, park facilities, and visitor experiences in the Valley. Implementation of actions presented in the Yosemite Valley Plan will further the park’s goals of restoring, protecting, and enhancing the resources of the Yosemite Valley; providing opportunities for high-quality, resource-based visitor experiences; reducing traffic congestion; and providing effective park operations. Many of the over 250 actions will result in restoration of developed and disturbed areas to natural conditions, redevelopment of some areas, and development of other areas to accommodate visitor and employee services.  Most of the actions proposed in the Yosemite Valley Plan would take place in the east Valley, east of El Capitan; the Yosemite Valley Plan proposes minimal construction in the west Valley. 

In order to implement many of the actions called for in the Yosemite Valley Plan, existing utility facilities in the east Valley must be upgraded, relocated and/or removed, or abandoned in place. Currently, east Valley utilities exist primarily in underground corridors that are dispersed throughout the east Valley, including in environmentally sensitive areas such as the riverbed, wetlands, meadows, and cultural resource sites.  Development of a utilities improvement plan is needed to provide long-term guidance to utility infrastructure relocation and improvement.  This will ensure that the utility system developed maximizes the efficiency of utility operations and minimizes adverse impacts on the park’s natural and cultural resources. Where possible, various utilities will be consolidated into integrated corridors to ensure adequate service to existing and proposed facilities. The integration of utilities into fewer corridors will reduce existing operation and maintenance impacts on park natural resources.  This will be achieved by removing some utility infrastructure in the riverbed and floodplain and relocating utilities out of environmentally sensitive areas, thus facilitating the proposed ecological restoration of those areas identified in the Yosemite Valley Plan. The East Yosemite Valley Utilities Improvement Plan was developed to achieve these goals. This project was called the Yosemite Valley Integrated Utility Master Plan during the public scoping process.  The name has been changed to the East Yosemite Valley Utilities Improvement Plan to more accurately reflect the scope of the project, which looks at utility improvements in the east Valley, from the Yosemite Creek Lift Station to the park water storage tank near Happy Isles.

The East Yosemite Valley Utilities Improvement Plan identifies potential utility corridors in the east Valley that would (1) allow for efficient consolidation of utilities, (2) maximize use of existing and proposed transportation corridors, and (3) minimize use of environmentally sensitive areas.

The specific utilities addressed in the East Yosemite Valley Utilities Improvement Plan include wastewater, potable water (referred to hereafter as water), electric, and, to a limited extent, communications facility improvements located in the east Valley.  The east Valley area evaluated for this project consists of the area from the Yosemite Creek Lift Station on the west to the park water storage tank in the Happy Isles area on the east (figure I-1). 

Purpose Of and Need For the Project

Over the last several decades, the existing utility infrastructure serving Yosemite Valley was developed incrementally as needed.  A variety of different underground utility corridors were constructed throughout the Valley to provide service to various facilities.  As a result, there has been no unified approach to infrastructure siting, and existing utility lines criss-cross the Valley.  Wastewater, water, electric power, and communications lines are located primarily in individual underground corridors, with multiple utility corridors serving the same developed areas. Many of these utility corridors cross river- and creekbeds, meadows identified in the Yosemite Valley Plan for ecological restoration, and other environmentally sensitive areas.

Most of the utilities in Yosemite Valley are currently in adequate condition, although there are many exceptions. In particular, the wastewater collection system is in poor condition in several areas. Yosemite National Park is currently under a Cleanup and Abatement Order from the California Regional Water Quality Control Board related to the park’s wastewater facilities (Appendix A). The order requires the park to make improvements to the wastewater collection facilities to ensure protection of human health and water quality. These improvements include both short- and long-term projects to ensure that the park has a safe and effective wastewater collection system. Non-compliance with the state order could result in fines and required closure of certain park and visitor facilities. Due to the immediate nature of the wastewater collection system issues, the National Park Service has developed a Capital Improvement Program for Yosemite Valley to implement emergency repairs and upgrades. These required repairs are included in the discussion of all of the alternatives in this environmental assessment.

The present water system was originally constructed in the early 1940s and 1950s, and substantial improvements occurred in the late 1980s.  Although this system is generally adequate, recent hydraulic testing has shown a need for improvements to ensure that major facilities have adequate fire flows and system reliability.  Similarly, an evaluation of the electric system revealed the need for upgrades to address existing condition and load requirements to ensure safe and reliable service.  Existing communications facilities in Yosemite National Park currently have a limited capacity for digital data transmission. As the park implements some of the transportation actions called for in the Yosemite Valley Plan and increases its use of remote electronic controls for utilities and other infrastructure, the need for reliable data transmission will increase. Consolidated utility corridors will provide the park with the ability to improve communications and data transfer infrastructure in the future.

The purpose of this project is to develop an East Yosemite Valley Utilities Improvement Plan that will guide the phasing, upgrade, relocation, and consolidation of various utilities into fewer underground utility corridors than currently exist in the east Valley. There is a need for a utilities improvement plan that will:

§         Ensure adequate service to east Valley facilities relocated or developed under the Yosemite Valley Plan

§         Implement upgrades needed to address previously identified utility condition and capacity issues

§         Maximize use of existing transportation and utility corridors and proposed new transportation corridors

§         Minimize potential future impacts to environmentally sensitive areas

§         Protect and preserve the Merced Wild and Scenic River as called for in the Merced Wild and Scenic River Comprehensive Plan (Merced River Plan) (NPS 2001)

The need for this project was identified during the development of the Yosemite Valley Plan. The existing utilities have problems due to age and poor condition, inadequate collection and distribution capacity, inaccessibility to those areas proposed for development, and inappropriate location of existing utilities in environmentally sensitive areas. Development of the East Yosemite Valley Utilities Improvement Plan will provide a long-term “blueprint” for utilities in the east Valley and allow the National Park Service to efficiently repair and replace wastewater infrastructure within the context of the long-term plan for these facilities. The result will be a utility system that maximizes the efficiency of utility operations and maintenance and minimizes the potential for future environmental impacts.

Planning Context

Relationship to Yosemite National Park Plans

Planning in Yosemite National Park takes two different forms: general management planning and implementation planning. General management plans are required for national parks by the National Park and Recreation Act of 1978. The purpose of a general management plan is to set a “clearly defined direction for resource preservation and visitor use” (NPS 1998a) and provide general directions and policies to guide planning and management in the park. The 1980 General Management Plan is the overall planning document for Yosemite National Park.

The Merced Wild and Scenic River Comprehensive Management Plan (Merced River Plan) is a general management plan that guides management of the Merced Wild and Scenic River Corridor. In designating the Merced River as a Wild and Scenic River, Congress authorized the National Park Service to prepare its management plan for the river by making appropriate revisions to the park’s 1980 General Management Plan (16 USC 1274[a][62]). The Merced River Plan, which amended the General Management Plan in some respects, provides a framework for decision-making on future management actions within the Merced Wild and Scenic River corridor. The East Yosemite Valley Utilities Improvement Plan will comply with conditions outlined in the Merced River Plan.

Implementation plans, which tier off of the General Management Plan and Merced River Plan, focus on “how to implement an activity or project needed to achieve a long-term goal” (NPS 1998a). Implementation plans may direct specific projects as well as ongoing management activities or programs and provide a more extensive level of detail and analysis. The Yosemite Valley Plan is an implementation plan that presents a comprehensive management plan for Yosemite Valley. The Yosemite Valley Plan guides protection of natural and cultural resources, opportunities for high-quality resource-based visitor experience, reduction of traffic congestion, and effective park operations. The East Yosemite Valley Utilities Improvement Plan would assist in implementation of actions called for in the Yosemite Valley Plan; therefore, this project is tiered off the Yosemite Valley Plan.

Regulations, Policies, and Management Goals

Regulations and Policies

The East Yosemite Valley Utilities Improvement Plan Environmental Assessment is written within a complex set of regulations and policies. The East Yosemite Valley Utilities Improvement Plan must not only comply with requirements of the National Environmental Policy Act (NEPA)and the National Historic Preservation Act, but it must do so within the parameters of other legislation that governs land use within Yosemite National Park (Appendix B).

National Park Service Organic Act

In 1916, the Organic Act established the National Park Service in order to “promote and regulate the use of parks …” and defined the purpose of the national parks as “to conserve the scenery and natural and historic objects and wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.” This law provides overall guidance for the management of Yosemite National Park.

The Prohibition on Impairment of Park Resources and Values

The Organic Act establishes the management responsibilities of the National Park Service. While Congress has given the National Park Service management discretion to allow certain impacts within parks, that discretion is limited by the statutory requirement that park resources and values be left unimpaired, unless a particular law directly and specifically provides otherwise. This cornerstone of the Organic Act establishes the primary responsibility of the National Park Service. It ensures that park resources and values will continue to exist in a condition that allows the American people to have present and future opportunities for enjoyment of them. National Park Service Management Policies 2001 provides additional guidance on impairment of park resources and values.

Management Goals

Management goals identify long-range direction for Yosemite National Park. Any proposed project must carefully balance multiple goals, especially in a park as large and complex as Yosemite. Goals from Yosemite’s General Management Plan, the Merced River Plan, and Yosemite Valley Plan are presented below.

General Management Plan Goals

The General Management Plan for Yosemite National Park sets forth the following five broad goals for management of the park as a whole:

§         Reclaim priceless natural beauty

§         Allow natural processes to prevail

§         Promote visitor understanding and enjoyment

§         Markedly reduce traffic congestion

§         Reduce crowding

Merced River Plan Goals

While the Merced River Plan adopts the five broad goals from the General Management Plan, it also outlines an additional set of goals for management of the Merced Wild and Scenic River. The main stem and South Fork of the Merced River were designated by Congress in 1987 for protection under the Wild and Scenic Rivers Act. The National Park Service developed the five goals of the Merced River Plan to further the policy established by the Wild and Scenic Rivers Act, namely, to preserve designated rivers in their free-flowing condition, and protect and enhance the river’s Outstandingly Remarkable Values. The Merced River Plan goals include:

§         Protect and enhance river-related natural resources

§         Protect and restore natural hydrologic and geomorphic processes

§         Protect and enhance river-related cultural resources

§         Provide diverse river-related recreational and educational experiences

§         Provide appropriate land uses

The Merced River Plan applies seven management elements to prescribe desired future conditions, typical visitor activities and experiences, and park facilities and management activities allowed in the river corridor. The management elements as they relate to the East Yosemite Valley Utilities Improvement Plan are discussed in Chapter V, Merced Wild and Scenic River. The Wild and Scenic Rivers Act Section 7 determination is included in Appendix C.

Yosemite Valley Plan Goals

The Yosemite Valley Plan carries forward the goals of the General Management Plan. In addition, the Yosemite Valley Plan identifies four specific purposes of the plan. These include:

§         Restore, protect, and enhance the resources of Yosemite Valley

§         Provide opportunities for high-quality, resource-based visitor experiences

§         Reduce traffic congestion

§         Provide effective park operations, including employee housing, to meet the mission of the National Park Service

The Yosemite Valley Plan also identifies criteria for accomplishing the broad goals of the General Management Plan in Yosemite Valley and the specific purposes of the Yosemite Valley Plan. The criteria include:

§         Protect and enhance natural and cultural resources

§         Enhance visitor experience

§         Provide effective operations

§         Provide appropriate land uses

Issues and Concerns

The following issues were identified during the public scoping process (see Chapter VI, Consultation and Coordination) and through input from National Park Service staff. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Natural Resources

Hydrology, Water Quality, and Wetlands

Utilities constructed throughout the Valley have affected groundwater and surface water flows, particularly in meadow, wetland, and riparian areas. The proposed action could adversely impact existing hydrologic conditions in some areas and could help restore historic water flows in others. Wetland areas could be adversely affected by new utility corridors or could benefit from removal of utilities in some areas. Concerns were raised regarding the potential for water quality impacts associated with construction activities in environmentally sensitive areas and the need for Best Management Practices to address water quality. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Fish, Wildlife, and Plant Habitat

Yosemite Valley supports diverse aquatic and riparian habitats for plant and wildlife species. The proposed action could adversely affect these habitats through loss of vegetation and habitat, disturbance of wildlife, and the introduction of invasive, non-native species. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Air Quality

Yosemite National Park is a Class 1 airshed (under the Clean Air Act) and therefore must maintain the highest standard of air quality. Air quality could be adversely affected by construction activities associated with the proposed action. Best Management Practices are needed to control dust and other air emissions during construction. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Cultural Resources

Archeological Resources

Yosemite Valley has been occupied by American Indians for thousands of years, and significant archeological sites are present throughout the east Valley. The proposed action has the potential to disturb archeological sites, particularly during construction activities. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Traditional Cultural Resources

Yosemite National Park is part of a living tradition for local culturally associated American Indian groups. Many areas of Yosemite Valley are important for traditional cultural uses and practices, including the gathering of plant materials for food, basketry, and other uses, and the conducting of traditional ceremonies. The proposed action could affect usage of these areas. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Cultural Landscape Resources, Including Historic Sites and Structures

Historically significant structures and landscapes exist throughout Yosemite Valley. The proposed action could adversely affect these structures or landscapes. These issues are addressed in the analysis presented in Chapter IV, Environmental Consequences.

Organization of this Environmental Assessment

The proposed action and alternatives for the East Yosemite Valley Utilities Improvement Plan (and the evaluation of potential impacts of these alternatives) are integrated in this document and will be referred to collectively as the East Yosemite Valley Utilities Improvement Plan Environmental Assessment. The contents of this document area as follows:

§         Chapter I, Purpose and Need – The first chapter includes a discussion of the project’s purpose and need, planning context, relationship to management goals and objectives, and the scope of this environmental assessment.

§         Chapter II, Alternatives – This chapter discusses the No Action Alternative and action alternatives under consideration by the National Park Service for the East Yosemite Valley Utilities Improvement Plan and provides a set of summary tables comparing the alternatives.

§         Chapter III, Affected Environment – This chapter provides an overview of the affected environment, describing the existing condition of natural resources, cultural resources, and social resources in the East Yosemite Valley Utilities Improvement Plan project area.

§         Chapter IV, Environmental Consequences – This chapter presents the analysis of the potential environmental impacts of each alternative.

§         Chapter V, Merced Wild and Scenic River – This chapter analyzes the consistency of the proposed action with the management elements of the Merced River Plan.

§         Chapter VI, Consultation and Coordination – This chapter summarizes how this environmental assessment was prepared and reviewed.

§         Chapter VII, List of Preparers – This chapter lists the names and qualifications of the persons who are primarily responsible for preparing and reviewing this document.

§         Chapter VIII, Glossary – This chapter defines the technical terms and acronyms used in this document.

§         Chapter IX, Bibliography – This chapter lists the references cited in this document.

In addition to the above, appendices to this environmental assessment provide additional supporting data and information as necessary.