TED Case Studies

NUMBER : 449

MNEMONIC : Yosemite


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I. Identification

1. The Issue

Over the past 15 years, the level of visitation to Yosemite has increased dramatically to over four million visitors per year, causing a multiplicity of adverse effects on the valley's habitat. This case focuses specifically on the detrimental effect of vehicular traffic associated with high levels of visitation in Yosemite National Park. Automobiles in the park cause traffic congestion, the need for more parking lots and broader roads, and noise, air, and visual pollution in the park, damaging the plethora of flora and fauna species residing in the park, while also detracting from the visitor experience. Although the richness of the experience is diminished with problems of automobile traffic, tourism continues to grow. Moreover, strong public support for the implementation of traffic restrictions suggests that stricter controls will not hinder the continued expansion of tourism. Rather, it will transform the current visitation into true 'eco-tourism'. The Yosemite National Park Service administration, part of the U.S. Department of the Interior, is faced with the task of determining the most sustainable, cost-effective, and beneficial method of reducing traffic in the park. The GMP stipulates that park management should strive for the eventual removal of all vehicular traffic from Yosemite. Current adoption of the Valley Implementation Plan (VIP) has been delayed to fall 1997 and is contingent upon further negotiations with surrounding communities, and sufficient funding.

2. Description

"Though of such stupendous depth, these canyons are not gloomy gorges, savage and inaccessible. With rough passages here and there they are flowery pathways conducting to the snowy, ice fountains; mountain streets full of life and light, graded and sculptured by the ancient glaciers, and presenting throughout their courses a rich variety of novel and attractive scenery - the most attractive that has yet been discovered in the mountain ranges of the world." -- John Muir, The Yosemite.

John Muir's description of Yosemite Valley's astonishing beauty captivates the reason why four million people visit the national park each year. Sierra Club President Adam Werbach summed it up when stating that "In the last 15 years, Americans have nearly loved Yosemite to death, their swelling numbers causing gridlock and smog in the Park." The alarming rate at which tourism in Yosemite continues to grow has given Yosemite National Park Service managers and conservation groups such as the National Parks and Conservation Association (NPCA) and the Sierra Club cause to worry. Torn between a need to preserve the park's resources and a duty to share its splendor with all, park officials have been working since 1980 to implement the Yosemite General Management Plan (GMP) which seeks to "reclaim priceless beauty, reduce cars and congestion, and allow natural processes to prevail." The GMP represents the first long-term planning project for the evolution of the park, and is a response to public concern regarding Yosemite's future.

Click on Map for Full Size A. HISTORY

The Yosemite Valley's history began approximately 10,000 years ago during the Tioga glaciation when the Tioga glaciers retreated up the Merced Canyon carving the mountains and creating the Valley floor. The Valley is believed to have been permanently inhabited close to 3,500 years ago by the ancestors of the Southern Sierra Miwok tribe. The Yosemite Miwok called their home 'Ahwahnhee' meaning 'valley that looks like a gaping mouth', and lived a peaceful and balanced life prior to the white man's arrival. The Miwok left Yosemite in the cold winter months to live in the milder climate of the foothills and returned in late spring to gather food (berries, greens, bulbs, seeds, and acorns) and to hunt (deer, trout and rabbit) (The History of Yosemite: Ahwahnee).

The Ahwahneechee's harmonious existence came to an end with the advent of the gold rush in 1848. Argonauts scoured the countryside and poured into the central Sierra foothills. In their frenzied haste to discover gold, the prospectors laid waste to much of the valley's resources and food sources. This led to conflict between the Miwok and the 49ers which escalated into violent clashes between the two groups. In 1851, the Mariposa Battalion captured the Ahwahneechees and their chief Tenaya, and relocated them to the Fresno River Reservation. Two years later, some were permitted to return to the valley, but they eventually scattered throughout the Sierra after Chief Tenaya was killed.

Tourism in the Valley began as early as 1855 when James Mason Hutchings from San Francisco, accompanied by artist Thomas Ayres, and Galen Clark first organized a tourist expedition into Yosemite. This visit changed the course of Yosemite's history instantaneously as Hutchings' publications and praises drew visitors and homesteaders into the Valley (The History of Yosemite : Ahwahnee). Hotels and homes were built, lands were cleared for crops, and livestock grazed in the meadows, presenting the first assault on Yosemite's fragile and complex ecosystem.

Thankfully, a few individuals were foresighted enough to recognize the necessity of protecting the park from further abuse. On June 30, 1864, Jessie Benton Fremont, I.W. Raymond, and Frederick Law Olmstead succeeded in their efforts to convince the Federal government to grant the Yosemite Valley and the Mariposa Grove of Big Trees to the State of California for their preservation and protection. Hence, the Yosemite Land Grant became the United States' first state park.

In its early days, the Yosemite State Park witnessed unprecedented growth. Roads were built, visitation levels boomed, and hotels sprang up throughout the Valley. The park's commissioners were faced with the same problem which still exists today : how to balance park visitation with park preservation. These events caught the eye of John Muir, a Yosemite resident who had first worked as a sheepherder, and later as a sawmill operator in the Valley. Muir despaired at the park's destruction and mounted a successful campaign with New York Century magazine editor Robert Underhill Johnson to make Yosemite a national park similar to Yellowstone National Park which was created in 1872. In 1890, the Valley was established as Yosemite National Park under the auspices of the National Park System. Soon after, the U.S. Cavalry began its task of protecting the park in its natural condition.

Yet conservationists faced their greatest challenge a short while thereafter with regards to San Francisco's bid for water rights to the Tuolumne River in Hetch Hetchy Valley (The History of Yosemite : Ahwahnee). Although the city was initially denied access, the Hetch Hetchy dam was built in 1934 after the Great San Francisco Earthquake of 1906 burned most of the city. This was one of the few times in Yosemite's history when visitation levels dropped drastically from 10,000 in 1905 to 5,414 in 1906.

World War I necessitated the departure of the U.S. Cavalry and the creation of a year-round civilian park service, which introduced such programs as the educational program which hosted a series of guided nature walks and informational literature. During this time, the Park Service continued its dilligent work to preserve the park while building new roads for the first visits by automobile.

During the Second World War, 90,000 troops occupied Yosemite Valley for military training. This marked the second time in Yosemite's history when visitation levels decreased significantly. The grand Ahwahnee Hotel was utilized not as a respite for tourists, but as a Navy hospital.

After WWII, tourism in the park began to grow sharply and park management had a difficult time addressing the multifarious issues that the increase in visitors presented (The History of Yosemite : Ahwahnee). By the early 1970s, theft, fights, drugs, and rapes occurred in the Valley culminating in a Fourth of July riot in 1970. Moreover, automobile traffic has intensified in conjunction with the increase in tourism and has taken a significant environmental toll. Air pollution, especially during the busy summer months, has often produced a dense smog in the Valley, damaging the multifarious plant and animal species which reside in the park. Noise pollution from vehicles and campsites rivals the park's natural noises (Yosemite National Park Planning Update). Buildings, roads, and parking lots have marred the aesthetic beauty of the Valley, while visitors are often stuck in traffic hoping to find a parking spot.

Efforts to curb automobile traffic began in the early 1970s as the first free shuttle bus service was initiated. Even then the notion of working for a car-free Yosemite existed. This idea has been carried through to the present and is documented in the General Management Plan of 1980, which seeks to address the park's present and future needs.


The GMP proposes the eventuality that all private vehicles be banned from the park and non-essential roads and buildings be relocated outside of the park. It is comprised of the 'Visitor Use, Park Operations, and Development Plan for Yosemite National Park', the 'Natural Resources Management Plan', and the 'Cultural Resources Management Plan.' The Valley Implementation Plan (VIP) can be considered the working copy of the GMP and will work to improve valley "access and circulation, remove unnecessary roads and buildings, and reclaim priceless beauty while enhancing visitor enjoyment." Its release has been delayed until fall 1997 as a result of scarce resources, and major flooding and subsequent damage to the park.

The issue of vehicular traffic, deemed one of the most important issues facing the valley today, has been addressed in the Alternative Transportation Modes, Feasibility Study (Transportation Study), released in 1995. It presents two options for intercepting day-use traffic (which is thought to be growing due to the increased number of visitors living in close enough proximity to visit the park for the day). The first option is to create a system of staging areas outside the park, which would intercept day-use traffic and transfer this traffic via shuttle to a circulator system inside the park. The second option calls for a single staging area located within the park to intercept traffic from which visitors would transfer to the afore-mentioned circulator system. Of the two options, the National Park Service selected the second as being the most desirable, cost-effective, and environmentally sustainable. However, due to public reaction calling for reconsideration of these options in favor of more drastic measures, this decision has beenpostponed in order to further consult with surrounding regions about other options (Message from the Superintendent).

The 1997 summer season in Yosemite was to have seen the advent of the Valley Reservation System (VRS) in which private automobiles required a prior reservation to enter the park on a given day. Those parties not having a reservation would be shuttled into the park ending space. The Californian public, which comprises roughly 70% of Yosemite yearly visitation, overwhelmingly supported the VRS in a public opinion poll last spring. 83% of Californians approved of establishing VRS in the summer 1997, while 73% of Californians support making the VRS a permanent part of the Yosemite operating system (Uher, Jerome). Thus, consensus between Yosemite park service and a large part of the tourist population exists. Solving Yosemite's problem of vehicular pollution and congestion requires foresight, sufficient funding, and agreement on the exact means of reaching this end.

This strong public support for the transformation of Yosemite's operations with regards to tourism seem to indicate that visitors are willing to follow park management's lead in what concerns the implementation of the GMP. More importantly, restrictions on automobiles in the park should not affect tourists' decisions to visit the park. Taking full advantage of national parks in the U.S. to learn of our natural and historic heritage is a fundamental element of American citizenship. Yosemite's sustainable evolution will thus continue to be upheld by American society as a balance will be struck between preservation and visitation.

Although 80% of the park's visitors are currently from the United States, 20% come from foreign countries to marvel at Yosemite's wonders (More Footsteps Approach). The Valley is considered the most international destination in Central California. One may reason that increasing levels of visitation to the park may one day lead to the restriction of foreign visitation so that only Americans can take advantage of this treasure. However, neither the General Management Plan nor any other relevant source has mentioned this eventuality as of yet. The National Park Service is working to create true eco-tourism in which all are able to participate in Yosemite's splendor while maintaining the park's natural ecological processes.

The Valley's ecological processes are complex to manage indeed. The Park Service's efforts to maintain the pristine state of Yosemite's wilderness has had mixed effects. Peregrine falcons are nurtured by technical climbers, some wild bighorn sheep have been returned to high craggy ridges, and prescribed burns take place as part of a larger effort for preventing fires. Yosemite's management has also been taking trees out of the Merced River to protect rafters and bridges. However, these actions are often performed without consideration of their consequences on the larger ecosystem and have often had adverse effects (Yosemite National Park Planning Update). As the administration's experience in Yosemite grows, a realization that interfering with Mother Nature poses many unforseen problems dictates the GMP's goals :

"The primary objective of natural resource management programs will be to restore and perpetuate the natural processes of the park's ecosystems. The Yosemite environment is not a static accumulation of geologic and biologic features but rather a dynamic system of interrelated and evolving forms. Therefore, if this environment is to be preserved, the natural processes that are occurring there must be understood and allowed to prevail. In developed areas like the Valley, facilities will be removed from floodplains and geologic hazard areas in deference to these natural phenomena, and the natural role of fire in vegetative communities will be simulated with controlled burns or mechanical removal of vegetation. In areas that have been disturbed by man's activity, natural processes will be allowed to restore the scene (GMP 1980)."

3. Related Cases














Key Words: North America, United States, Services, Eco-Tourism, Pollution, Habitat

4. Draft Author:

Stephanie F. Goeller (December 1997)

II. Legal Clusters

5. Discourse and Status:

Agreement and In Progress

Yosemite Park Management has delayed its planned implementation of the Valley Implementation Plan (VIP,) in order to further consult with surrounding communities, and to respond to suggestions made by the California public.

6. Forum and Scope:

United States and UNILATeral

The U.S. Department of the Interior, National Park Service, and Yosemite Park Management are involved in this case and participate in the discussion and planning of ecotourism in Yosemite. The U.S. Department of the Interior is specifically involved with regards to allocating funds for the implementation of the GMP, and the Yosemite Park Management is that group which is directly responsible for both ecological preservation and vistiation management in the Park.

7. Decision Breadth:

1 (United States)

8. Legal Standing:

Sub-Law : Yosemite National Park is governed by the National Park Service's statutes.

III. Geographic Clusters

9. Geographic Locations

a. Geographic Domain: North America

b. Geographic Site: Western North America

c. Geographic Impact: United States

10. Sub-National Factors:


11. Type of Habitat:


IV. Trade Clusters

12. Type of Measure:

Regulatory STANDARD

13. Direct v. Indirect Impacts:


14. Relation of Trade Measure to Environmental Impact

a. Directly Related to Product: Yes, TOURism

b. Indirectly Related to Product: No

c. Not Related to Product: No

d. Related to Process: Yes - Air, Noise, Visual Pollution

15. Trade Product Identification:


16. Economic Data

Table 1.1
1905 10,000
1906 5,414
1915 31,000
1935 372,000
1945 40,000
1947 750,000
1954 1,008,031
1967 2,201,484
1976 2,600,000
1980 2,500,000
1984 2,842,942
1987 3,266,342
1990 3,234,207
1991 3,542,666
1992 3,952,495
1993 3,983,749
1994 4,105,755
1995 4,101,928

Together with Yellowstone, Yosemite is one of the most visited of U.S. National Parks. Table 1.1 shows that the tourist industry in Yosemite has grown at an alarming rate, reaching one million visitors in 1954, two million in 1967, three million in 1987, and four million in 1994. Only in two different periods did the visitation decrease markedly; the first in 1906 after the great San Francisco Earthquake, and the second during WWII when the park was used for military purposes. The numbers continue to grow rapidly, especially during the summer months (refer to Table 1.2 for monthly visitation).

As the volume of tourists increases, so does the number of vehicles entering the park. Yosemite Park is traversed by 196 miles of paved roads and 67 miles of graded roads, 30 miles of which bisect the Valley floor (GMP 1980). Upon these roads in 1993, there were 495 motor vehicle accidents and 131 D.U.I. arrests. In 1994, 527 motor vehicle accidents occurred, and 144 arrests were made for driving under the influence (National Park Service).

In 1995, the 4.1 million visitors visiting the park arrived in more than 1.4 million vehicles. In August of 1996 when the number of visitors exceeded 700,000, approximately 246,000 vehicles entered the park, averaging more than 22,000 visitors and almost 8,000 vehicles per day. The increase in automobile traffic is largely attributable to the growth of the surrounding region. This is due in part to the fact that more visitors are now able to make day-trips to Yosemite Valley by private vehicles (Yosemite Natioanl Park Planning Update).

In a statewide opinion poll, Californians overwhelmingly agreed (83%) that a day-use reservation plan should be used during the summer of 1997. 70% of Californians polled believed that the day-use reservation plan should be made permanent if it proved effective and beneficial. (As of this writing, the success of this program remains to be determined). A nation-wide poll addressing the importance of preserving national parks found that almost 80% of those polled do not oppose an increase in entrance fees in parks, provided that 100% of fees collected be used within the parks. Moreover, 75% of respondents were willing to pay an extra dollar a year in federal taxes to support national parks (Statement of Voorhees, Philip H.).

Table 1.2 Monthly Visitation (1990-1995)
Month 1990 1991 1992 1993 1994 1995
Jan 103,491 108,630 131,594 105,603 136,085 128,310
Feb 105,528 115,065 125,284 109,761 131,835 156,556
March 150,302 121,950 155,066 157,436 192,262 129,262
April 246,530 194,597 261,205 255,632 256,724 260,057
May 377,470 367,671 440,653 393,316 398,909 289,712
June 439,554 410,425 503,758 462,972 513,182 466,955
July 498,283 539,512 587,519 625,255 607,305 687,122
Aug 380,293 608,265 606,835 657,727 690,087 679,443
Sep 376,800 456,344 486,209 521,545 529,514 566,161
Oct 285,246 331,565 368,166 382,450 348,319 423,934
Nov 168,121 170,242 169,367 177,907 152,123 217,997
Dec 102,589 118,400 116,839 133,145 148,761 91,506
Data from National Park Service

17. Impact of Trade Restriction:

Projected to be High

The restriction of vehicular traffic in the park intends to reduce air, noise, and visual pollution, making tourists' experience in the park more enjoyable. However, the extent to which this occurs is dependent on the particular system implemented. In addition, only time will tell the impact of the new system on the total visitor experience.

18. Industry Sector:

Services (S) / Tourism

19. Exporters and Importers:


	% Tourists to Yosemite: 	United States 80% (70% California)

Foreign 20%

V. Environment Clusters

20. Environmental Problem Type:

Habitat Loss

Habitat loss in Yosemite is caused by the building and widening of roads and parking lots and is accompanied by various forms of pollution. Air pollution results from automobile emissions - The Sierra Club reports "smog so thick that Yosemite Valley could not be seen from airplanes(Yosemite General Mangament Plan Update)." This occassional smog is harmful to all species and vegetation inside the Park. However, the air quality in the Merced River Canyon is generally good (Yosemite National Park Planning Update). Noise pollution, a more immediate detriment, detracts from the pristine state of the park. Human noise in the Merced River Canyon caused by automobiles, trucks, buses, and motor homes is said to be of equal magnitude with the park's natural noise level, except near areas surrounding roads, lodging, and campgrounds where it is significantly higher (Yosemite National Park Planning Update).

Plans to widen roads such as El Portal Road also threatens to encroach upon rivers, disturb roadside vegetation (i.e. among others, Chaparral - Chamise, Manzanita, Coanothus, and Mountain Mahogany), and cause the temporary loss of den and nest habitats on rock slopes.

21. Name, Type, and Diversity of Species

Name: Many

Type: Many


-84 mammal, 224 bird, 33 reptile and amphibian, 7 fish, and numerous invertebrate species.

-1,374 vascular plant species, and numerous ferns, bryophytes, and lichens

22. Resource Impact and Effect:

HIGH and Scale

23. Urgency and Lifetime:

HIGH and Hundreds of Years

24. Substitutes:


VI. Other Factors

25. Culture:


26. Trans-Boundary Issues:


27. Rights:


28. Relevant Literature

"Citizen Group Supports Yosemite Reservation System 'Visitors and Park Resources Would Both Benefit'," National Parks and Conservation Association. March 14, 1997.

"Construction, Roads and War, 1930-1950,"The Modesto Bee. 1990.

"Environmental Assessment for El Portal Road Improvements," Yosemite National Park Planning Update. Volume 7, Summer 1997.

"General Management Plan," Yosemite National Park, U.S. Department of the Interior / National Park Service. September 1980.

"The History of Yosemite: Ahwahnee," www.terraquest.com/highsights/valley/yosemite.

"Increasing Tourism Requires a Management Plan," Yosemite National Park, Compugraph Publishing.

"Message from the Superintendent," Yosemite National Park Planning Update. Volume 1, Fall 1995.

"More Footsteps Approach," The Modesto Bee. 1990.

"Pacific Regional Report," National Parks and Conservation Association. September 20, 1995.

"Parkwide Policies and Programs," General Management Plan, Yosemite National Park. U.S. Department of the Interior / National Park Service. September 1980.

"Public Supports Vehicle Reservation System at Yosemite. Poll Also Finds Strong Backing for Relocation of Flood-Damaged Buildings," National Parks and Conservation Association. February 18, 1997.

"Statement of Philip H. Voorhees National Parks and Conservation Association Before the Subcommittee on National Parks, Forests and Lands on H.R. 2025 and H.R. 2107, Bills to Change the Structure of Entrance and Recreation Fees in National Parks," August 3,1995.

"Transit Experts Come to Yosemite," National Parks and Conservation Association. May 1996.

"Yosemite General Management Plan Update," Sierra Club. www.sierraclub.org/chapters/ca/yosemite/update.html

"Yosemite Notebooks, Yosemite Visitation by Month," Yosemite National Park Notebooks.

"Yosemite May Visitation Near Normal," News Release, U.S. Department of the Interior / National Park Service. June 23, 1997.

"Yosemite August Visitation Sets Record," News Release, U.S. Department of the Interior / National Park Service. September 17, 1997.

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