Trans-Sierra Highway

Even in an age of interstate highways and powerful motor vehicles, the Sierra Nevada remains a significant barrier for eastward travel from California's Central Valley. But the absence of a road bisecting the range for 270 miles from Walker Pass in the south to Tioga Pass in the north is a product of historical forces as well physical geography.

Several plans for highways across the central Sierra Nevada were proposed in the 1920s. The fact that none were built reflects the growing strength of conservationists. But the relatively low elevation of Mammoth Pass continued to attract the attention of business interests in the Central Valley, and when the High Sierra and Minarets primitive areas were designated west of the Middle Fork Valley in 1931, legislators left a five-mile gap between them to allow for the possible construction of a highway.

The possibility resurfaced in the mid-1950s when representatives from Fresno, Madera, and Merced Counties began lobbying for the road as necessary for reaching the "rich markets to the east." After a 1957 study by the Bureau of Public Roads and the US Forest Service concluded that such a road was feasible, Mammoth area residents gathered hundreds of signatures on a petition opposing the highway, laying the groundwork for a local movement.

While the highway may have been possible from an engineering standpoint, construction wouldbe difficult and expensive. In 1966, California state highway engineer J.C. Womack concluded that several large bridges would be needed to cross steep canyons and snow-removal costs would likely exceed that of any other highway in the state. Womack later warned that "alignment easterly of the Devil's Postpile would, due to terrain, be so near the famous Postpile columns that heavy construction (blasting) could possibly cause damage to these columns." Womack recommended that neither state nor federal funds be allocated for the project. Some state legislators, however, continued to be swayed by a powerful Central Valley constituency of agricultural interests, newspapers, public lands committees, and private citizens.

The Park Service either ignored or was unaware of Womack's report and took no official position on the Minaret Summit Highway, as it came to be known. It would not pass within the boundaries of Devils Postpile National Monument, but it would increase visitation, require relocation of the entrance road, and benefit Yosemite National Park by relieving traffic pressure on Tioga Road. Although many North Fork Mono tribe members initially supported the highway as an economic opportunity, after much discussion, the tribe decided that the economic benefits were insufficient to counter arguments for maintaining as much of the traditional value of the land as possible.

Representative Bernie Sisk of Fresno, the primary advocate for the highway, promoted it as a way to extend recreational access to the Mammoth Lakes area to those of "modest means" who could not afford a pack trip or the time and expense then required to reach the area. In the early years, many tourism businesses in the Eastern Sierra assumed that any increase in accessibility would be good for business, but the highway's most vocal opponents were in the Mammoth area. In 1966, a group of recreational business owners and residents formed the Mono County Resources Committee to organize local opposition and mount a letter-writing campaign, targeting conservation organizations, the National Park Service, the US Forest Service, and state and federal legislators.

The environmental impact statement issued in March 1971 concluded that the road would have "substantial adverse impacts" including the visual intrusion of the retaining walls on the wilderness and increased visitation would result in "deterioration of the fragile soils and vegetation, as well as the fish, wildlife and timber supply" at recreation areas. The report's finding that "it is questionable whether more recreation should be encouraged at this location," epitomized the access issues that continued to define wilderness politics in this period.

In May 1971, Russell Train, chairman of the newly formed Council on Environmental Quality, urged the Federal Highway Administration to "terminate action" on all road proposals at Minaret Summit. The following year, the state of California issued a formal objection to the proposed highway, citing the Forest Service's inadequate assessment of the potential environmental impacts.

Thanks to local support from Lou and Marye Roeser, Doug Kittredge, Chip van Nattan, Genny Smith, and others, this issue was brought to the attention of Norman "Ike" Livermore Jr. Ike Livermore, a former packer in the Sierra, was the secretary of resources for Governor Ronald Reagan. Recognizing the effects this road would have on the recreational value and wilderness character of the Sierra, Livermore took the argument to Governor Reagan and Washington DC. During a 1972 pack ride through the Middle Fork Valley, Reagan announced that President Nixon opposed the highway and supported closing the wilderness gap. All parties involved celebrated in 1984 when the California Wilderness Act forever closed the wilderness gap by expanding the Ansel Adams Wilderness and preserving this area for future generations.

Last updated: September 22, 2015

Park footer

Contact Info

Mailing Address:

PO Box 3999
Mammoth Lakes, CA 93546


760 934-2289

Contact Us