Executive Summary

Transportation Directives

Transportation directives in the Mono County Regional Transportation Plan (RTP) include the following:

  • Correlate development of the transportation and circulation system with land use development;
  • Plan and implement a transportation and circulation system that is responsive to the County’s economic needs and fiscal constraints and that maintains the economic integrity of the county’s communities.
  • Plan and implement a transportation and circulation system that provides access to the county’s community, economic, and recreational resources while protecting and enhancing its environmental resources.
  • Develop and enhance the transportation and circulation system in a manner that protects the county’s natural and scenic resources and that maximizes opportunities for viewing those resources.
  • Plan and implement a resource-efficient transportation and circulation system that supports sustainable development within the county.
  • Provide for the development of a transportation and circulation system that preserves air quality in the county.
  • Plan and implement a transportation and circulation system that provides for livable communities, active transportation, and complete streets, while maintaining efficient traffic flow, emergency access and alternative transportation modes to the automobile.
  • Provide for an improved countywide highway and roadway system to serve the long-range projected travel demand at acceptable levels of service and to improve safety.
  • Maintain the existing system of streets, roads and highways in good condition.
  • Provide for the use of non-motorized means of transportation within Mono County.
  • Provide for the parking needs of residents and visitors, particularly in community areas.
  • Provide for the safe, efficient, and economical operation of the existing airports in the county.
  • Policies and programs in the Mono County RTP shall be consistent with state and federal goals, policies, and programs pertaining to transportation systems and facilities.
  • Provide for a community-based public participation process that facilitates communication among citizens and agencies within the region and ensures cooperation in the development, adoption, and implementation of regional transportation plans and programs. The desired goal is consensus regarding a system-wide approach that maximizes utilization of existing facilities and available financial resources, fosters cooperation, and minimizes duplication of effort.

Summary of Needs and Issues

Existing and future transportation needs and issues include the following:

  • Improving and maintaining state and federal highways since they are the major roadways in the county.
  • Maintaining and improving County roadways and obtaining additional funding to do so.
  • Ensuring that future development pays for its impacts on the local transportation and circulation system.
  • The California Transportation Commission (CTC) has suggested that improving the coordination between regional project planning and environmental streamlining would be the most effective way planning resources could be brought to bear for better project delivery. In response, there is the need to work with appropriate agencies such as Caltrans, the USFS, the BLM, the CDFW, the LTC, the County, and the Town of Mammoth Lakes to define environmental objectives, to design transportation projects in a manner that improves both the transportation system and the surrounding community and/or natural environment, and to incorporate environmental mitigation measures and enhancement projects into the planning process for transportation improvements to both state and local circulation systems.
  • Enhancing the scenic qualities of highway projects and related highway maintenance facilities, including efforts to expand scenic highway and byway designations in Mono County.
  • Increasing transit services at local, regional, and interregional levels in order to improve air quality, reduce congestion, and provide alternative methods of moving people and goods to and through the county.
  • Improving and expanding non-motorized facilities within and between community areas. There is the potential to link existing trail systems, which are predominantly on public lands, to newly developed trail systems on private and County lands in community areas, and provide wayfinding elements.
  • Providing adequate community parking facilities in community areas for all types of vehicles.
  • Encouraging additional carpooling and studying the potential to provide additional park-and-ride facilities.
  • Expanding air services and transit options at the Mammoth Yosemite Airport in order to help alleviate surface transportation problems in the town of Mammoth Lakes. Continued improvement of the airport facilities is necessary in order to expand services.
  • Correlating development of the transportation and circulation system with future land use development.
  • Ensuring that local transportation planning and programs are consistent with state and federal goals, policies, and programs pertaining to transportation systems and facilities.
  • Participating in regional transportation planning and projects, such as the Yosemite Area Regional Transportation System (YARTS) and joint planning efforts with Kern, Inyo, and San Bernardino counties, in order to develop an efficient regional system.
  • Continuing to increase public participation in the transportation planning process and ensuring that all shareholders in the local transportation system are represented in the planning process.
  • Residents of community areas throughout the unincorporated area of the county are concerned about providing safety improvements to the highway and roadway system and establishing and maintaining local trail systems for use by bicyclists, pedestrians, equestrians, and other non-motorized users.
  • The main issues in the town of Mammoth Lakes are improving air quality, reducing congestion, and maintaining the resort character of the town by providing additional pedestrian and bicycle facilities and by expanding year-round townwide transit service.
  • For those main streets that also function as California State Highways, improve coordination with Caltrans to balance local needs for a vibrant community street with the public’s need for roadways that provide local, regional and statewide connections. Just as mobility is essential to California’s economic and civic vitality, the planning, design and operation of main streets is tied to the prosperity and quality of life for local communities.

Summary of Transportation System

The transportation system in Mono County includes roadways, trails, paths, sidewalks, etc. for multi-modal use,[1] and serves transit service and air travel, as well as private cars and commercial trucking.Private automobiles are the primary mode of moving people; trucks are the primary mode of moving goods. Throughout the county, the transportation system is a key support system that sustains the social, economic and recreational activities in the county. The terrain, the weather and the lack of a sufficient population base to support them have limited other modes of transportation. These factors continue to restrict the development of alternatives to the existing transportation systems in the county.


US Highway 395 (US 395) is the principal route to and through Mono County. It is the primary route suitable for emergency purposes and the principal route to the county's many recreational and tourist attractions. US Highway 6 (US 6) and several state highways provide regional links to US 395 from adjacent areas of Nevada. US 395 also connects the county to central California across several routes subject to seasonal pass closures in the Sierra Nevada, including Highways120, 89 and 108. The highway system will continue to be the main access for both residents and visitors to and through the county.


The county currently has 684.15 miles of County-maintained roads. Although most of the County roadway system is established, there remains a need for new facilities in some community areas, in order to provide for emergency access and continued growth. Maintenance of existing roadways remains the highest priority for the County roadway system. The Town of Mammoth Lakes' roadway system is also mostly complete.


Transit services in the county currently include interregional and countywide services provided by the Eastern Sierra Transit Authority (ESTA) and the Yosemite Area Regional Transportation System (YARTS). Local services in the town of Mammoth Lakes are provided by ESTA and include private shuttle services. Countywide services are expected to increase in response to demand and the availability of funding; local services in the town are expected to increase as the Town implements its Transit Plan.


Three public airports are located in Mono County: Mammoth Yosemite Airport, Lee Vining Airport, and Bryant Field (Bridgeport Airport). The Town of Mammoth Lakes owns and operates the Mammoth Yosemite Airport; the County owns and operates the Lee Vining and Bryant Field airports. Planned improvements at the Lee Vining Airport and Bryant Field will increase safety at those airports. Planned improvements at the Mammoth Yosemite Airport will increase safety and expand the facilities to support additional commercial aircraft service.


Facilities specifically for non-motorized activities, such as bicycling, are limited. Many non-motorized activities occur on numerous trails and roads on public lands or on existing roadways where the shoulder may not be wide enough to accommodate the use. Policies in the RTP promote the development of additional non-motorized facilities for pedestrians, bicyclists, and Nordic skiers, primarily in community areas, in order to reduce dependence on the automobile, reduce air emissions, and increase the livability/walkability of local communities. RTP policies also promote the development of regional bike trails, such as the currently conceptual Eastern Sierra Regional Trail.


Summary of System Options and Alternatives

The existing transportation system in Mono County includes the highway and roadway system, transit services, aviation facilities, and non-motorized facilities (generally recreational facilities for bicyclists and pedestrians). Alternatives to the existing transportation system in the county are limited by the county’s isolation, topography, extreme weather conditions, small population, large distances between communities, large amounts of publicly owned land, and environmental constraints to developing additional facilities outside existing developed areas.


Due to these factors, the existing highway and roadway system will continue to be the major component of the transportation system in the county. Development of new alternative routes for highways and roadways during the 20-year time frame of this RTP is unlikely due to lack of demand for additional roads, fiscal challenges, topography, large amounts of publicly owned land, and environmental constraints to developing additional facilities outside developed areas. LTC policies now focus on asset management, on maintaining and enhancing existing facilities, instead of developing new ones.


The existing transportation system in the county (highway/roadway system, transit services, aviation facilities, non-motorized facilities) has been designed to accommodate increasing demand for those facilities and services over the 20-year time frame of this RTP. Demand for additional alternative methods of transportation, other than expanding and improving those currently existing in the county, is not anticipated to occur over the 20-year time frame of this RTP, given the constraints noted above.


Compliance with Air Quality Plan

Mono County and the Town of Mammoth Lakes meet all state and national air-quality standards except for particulate matter (PM10 ) and ozone. Mono County, the Mono Basin, and Mammoth Lakes are designated as non-attainment areas for the state PM10 standard. PM10 in the Mono Basin results primarily from windblown dust from the exposed lakebed of Mono Lake due to water export activities by the City of Los Angeles, and in Mammoth Lakes emissions are primarily from wood burning and re-suspended road cinders. Thus, in Mono County, transportation-related criteria pollutants occur only in Mammoth Lakes. As a result, the Great Basin Unified Air Pollution Control District’s Air Quality Management Plan for the Town of Mammoth Lakes, which serves as the required State Implementation Plan (SIP), contains the only transportation-related requirements in the county.


In 2014, the Town of Mammoth Lakes adopted an Air Quality Maintenance Plan and PM10 Redesignation Request to update the 1990 Air Quality Management Plan for the Town of Mammoth Lakes. The 2014 Plan updated Section 8.30.100B of the town Municipal Code which sets a peak level of VMTs (vehicle miles traveled) at 179,708 per day within the Town, and directs that the Town review development projects in order to reduce potential VMTs. A second budget of 66,452 VMT was established for a peak winter day in the area outside of the town boundaries (unincorporated county), but inside the boundaries of the
Mammoth Lakes PM10 planning area (Mammoth Air Basin). Methods to reduce VMTs include circulation improvements, pedestrian system improvements, and transit improvements. The 2013 Plan also requires the Public Works Director to undertake a street-sweeping program to reduce particulate emissions caused by road dust and cinders on Town roadways.


As of 2012, Mono County was designated as a non-attainment area for the state ozone standard. The State Air Resources Board concluded that ozone exceedance in the Great Basin Air Basin (Alpine, Inyo and Mono counties) was caused by transport from the San Joaquin Valley Air Basin; the Great Basin Unified Air Pollution Control District adopted an Ozone Attainment Plan for Mono County that identified the county as an ozone transport area.


Summary of Funding Programs

Funding for operations and maintenance of the transportation system in Mono County is expected to come from traditional revenue sources, i.e.:

  • Highways & Roads: Local Transportation Fund (LTF), State Highway Account, State Highways Operations and Protection Program (SHOPP), State Gas Tax, Regional Surface Transportation Program (RSTP), General Fund.
  • Transit: Transportation Development Act (TDA) including Local Transportation Fund (LTF), State Transit Assistance (STA), Federal Transit Assistance (FTA).
  • Aviation: California Aid to Airports Program (CAAP), General Fund.
  • Non-Motorized Facilities: General Fund.

Funding for transportation improvements is also expected to come from traditional revenue sources:

  • Highways & Roads: STIP funds.
  • Transit: STIP funds, Federal Transit Assistance (FTA) grants, State Transit Assistance, PTMISEA and Transit Security grants.
  • Aviation: California Aid to Airports Program (CAAP), Federal Aviation Administration (FAA) grants and local match, public/private partnerships.
  • Non-Motorized Facilities: STIP funds, Active Transportation Program (ATP), LTF.
  • Environmental Enhancement projects: Environmental Enhancement & Mitigation Program (EEMP).
  • Development Impact Fees may be utilized for transportation improvements related to new developments.

Summary of Public Participation in RTP Update

Public participation during the transportation planning process was provided through a number of committee meetings, public workshops, and outreach programs:

  • On an ongoing basis, the county Regional Planning Advisory Committees serve as citizens’ advisory committees to the LTC to identify issues and opportunities related to transportation and circulation in their community areas and to develop policies based on the identified needs.
  • Community meetings and workshops to address specific transportation issues have addressed pedestrian safety on US 395 in Lee Vining; Walkable Communities in Crowley Lake, Mammoth Lakes, June Lake, Lee Vining, and Bridgeport; 395 passing lanes in the Antelope Valley; Main Street planning in Bridgeport; regional corridor planning for 395; and other transportation issues.
  • The county Collaborative Planning Team is a multi-agency planning team that coordinates planning efforts in Mono County for a variety of needs (e.g., jobs, transit, trails, recreation, wildlife mitigation and enhancement, etc.). It includes representatives from the following organizations: Mono County, Town of Mammoth Lakes, Benton Paiute Reservation, Bridgeport Indian Colony, Bureau of Land Management, Caltrans, California Department of Fish and Wildlife, US Fish and Wildlife, National Park Service (Devils Postpile and Yosemite), Lahontan Regional Water Quality Control Board, Inyo National Forest, and the Humboldt-Toiyabe National Forest.
  • The Town of Mammoth Lakes used a Transit Technical Advisory Committee to assist in developing the Town’s Transit System Design and Development Plan.
  • Input from Native American communities in the county was provided through use of the transportation plans for the Bridgeport Colony and the Benton Paiute Reservation and through outreach programs to the county’s Native American communities. The Bridgeport Indian Colony has participated in the Bridgeport Regional Planning Advisory Committee (RPAC). Members of the unrecognized Mono Basin Tribe have participated in Mono Basin RPAC, while staff of the Benton Tribe has participated in the Benton/Hammil RPAC.
  • Input from persons with disabilities was provided through the unmet transit needs hearing process and through consultation with social services providers serving the disabled population in the county. In addition, the Inyo-Mono Counties Coordinated Public Transit-Human Services Transportation Plan provides information on transportation-related social services needs in the county.

Summary of Recommended Actions

The 2015 Mono County RTP Action Element includes the following recommendations:

  • Direct county Road Department funds to the operation and maintenance of existing roadways. Roadway construction or rehabilitation projects are limited to those eligible and included in the STIP. Both the RTIP and the STIP now include a preventative maintenance program.
  • In the short range, direct Town Road Funds to the operation and maintenance of existing roadways. Roadway construction or rehabilitation projects are limited to those eligible and included in the STIP.
  • The current adopted STIP for Mono County serves as the short-range highway improvement program. In the past, STIP projects have been confined to highway projects. Since the passage of SB 45, STIP funds are available for a variety of transportation improvement projects. As a result, although the STIP contains primarily highway projects, it also contains projects on county and town roads, as well as pedestrian and bikeway improvements, and transit projects. These are specific action items to be completed in the immediate future. General action plans, both short-term and long-term, for county and town roads, aviation, pedestrian facilities, and bikeway facilities are outlined in this RTP.
  • Caltrans' Interregional Improvement Program (IIP) serves as the long-range highway improvement program for this RTP.
  • The Lee Vining and Bryant Field airports are operated by the County. The County is seeking funding to update the comprehensive plans for these airports. An increase in transient activity is expected at the Lee Vining Airport due to a new emphasis on its proximity to Yosemite National Park.
  • Short-range action plans for the Lee Vining Airport and Bryant Field in Bridgeport are provided by the Capital Improvement Plan for each airport and include a number of safety improvements.
  • The Mammoth Yosemite Airport is owned and operated by the Town of Mammoth Lakes. Extensive improvements are planned for the Mammoth Yosemite Airport to enable the airport to support Bombardier QD400 commercial aircraft service. The short-range action plans for the Mammoth Yosemite Airport are provided by the Mammoth Yosemite Airport Capital Improvement Plan.
  • The action plans for transit focus on implementing policies in the Eastern Sierra Transit Authority’s (ESTA’s) Short-Range Transit Plan (SRTP) and the Town of Mammoth Lakes Transit Plan, both incorporated by reference in this RTP. Specific purposes of the ESTA SRTP are to analyze existing transit services and to provide a concise summary of those services, to evaluate the needs of county residents and visitors for transit services, to estimate future demand for transit services, to evaluate funding opportunities to sustain the long-term viability of the transit system, and to delineate policies for the future development and operation of transit systems in the county. Since adoption of the Transit Plan, ESTA has expanded its routes in response to needs identified in the SRTP and at annual unmet transit needs hearings.
  • The Town's Transit Plan and the Revised Transportation and Circulation Element of the Town’s General Plan contain policies that intended to increase transit ridership and reduce automobile usage. Recommended service improvements include expansion of winter transit services (peak period) for skiers and commuters, airport shuttle service, increased community transit services, year-round fixed-route services, and Dial-A-Ride services in Mammoth. Policies in the Transit Plan and Revised Transportation and Circulation Element also emphasize restricting automobile parking spaces in favor of expanding the existing transit system and direct ski lift-access facilities, and incorporating transit and pedestrian facilities into existing and future developments, in order to reduce vehicle trips and improve air quality.
  • Recommended actions that focus on interregional connections include continuing participation in the Yosemite Area Regional Transportation System (YARTS), in the intercity transit planning process with Inyo and Kern counties and Caltrans District 9, and in the Eastern California Transportation Planning Partnership, which is a collaborative regional transportation planning process with Kern, Inyo, and San Bernardino counties.
  • The County's action programs for bicyclists, pedestrians, equestrians, Nordic skiers and other non-motorized modes of transportation focus on implementing an updated Mono County Trails Plan (see Appendix), and adopting a Bicycle Transportation Plan. RTP policies call for the provision of wider shoulders for bike and other uses as a component of rehabilitation projects on streets and highways, and focus on walkable communities and increasing multi-modal mobility in the Livable Communities and Active Transportation policy elements.
  • The Town of Mammoth Lakes' action programs for bicyclists, pedestrians, and other non-motorized users focus on implementing the Town’s General Bikeway Plan and the Mammoth Lakes Trail System Plan.
  • Ensure active and continuous involvement in the STIP process to maximize funding opportunities for rehabilitation and construction projects throughout the county.
  • Implement maintenance activities on County non-paved roads to open public lands to ensure access to remote areas and to provide emergency access. Maintenance activities now focus on implementing environmentally sensitive operations in order to mitigate impacts to wildlife, such as sage grouse.

Summary of Significant Environmental Impacts

The effects of the RTP on the environment are analyzed in the 2015 Mono County RTP & General Plan Update Draft EIR, and significant environmental impacts are identified. Response to comments will be contained in the 2015 Mono County RTP & General Plan Update Final EIR, which will be available prior to the adoption of the RTP. For copies of the environmental documents, contact the Mono County Community Development Department at 760.924.1800 or visit http://monocounty.ca.gov/planning/page/mono-county-general-plan-update.


[1] As described by Caltrans District 9 in comments (dated September 28, 2015) submitted on the Draft Regional Transportation Plan and Environmental Impact Report.