Bridging the Gap Between Preservation and Conservation in Yosemite National Park

Posted on: November 26th, 2012 by National Trust for Historic Preservation

Written by Erica Stewart, Public Affairs

The Ahwahnee Bridge, Yosemite National Park (Photo courtesy Mary Rattner)

Thirty-five years ago on this day, the National Park Service added eight stone Rustic-style bridges in Yosemite National Park to the National Register of Historic Places.

This designation, unexpected because the bridges were less than fifty years old at the time, was in recognition of their “unique…architectural design” and “aesthetic considerations.” Built between 1928-1932, the bridges of Yosemite represent the second largest collection of Rustic style bridges in the entire park system -- second only to the south rim of the Grand Canyon -- and provide a stunning complement to the majestic natural beauty of the Yosemite Valley. They are also key contributors to a National Register-listed Historic District, which is based on its national significance.

Today, these bridges are at the center of a controversy that highlights the potential tension between cultural resource protection and natural resource conservation. The issue is that three of the bridges—the Stoneman, Awhahnee, and the Sugar Pine—are endangered by the Park Service’s preliminary proposals for managing the Merced River, a federally designated “Wild and Scenic River.”

The Wild and Scenic River status means that the National Park Service  must identify what it is that makes a river significant (its “outstandingly remarkable values,” or ORVs) and then develop a plan to protect them. Historic and cultural values are specifically identified as eligible values.

Remarkably, the Park Service failed to identify the river’s historic bridges or any other historic structures in the valley as ORVs. In fact, four of the five preliminary proposals suggested eliminating one or more of the historic bridges. This prompted the National Trust to place the bridges of Yosemite Valley on the 2012 11 Most Endangered Historic Places list, and name them as a National Treasure.

Stoneman Bridge, Yosemite National Park (Photo courtesy Lee Rentz)

Since then, the National Trust’s San Francisco Field Office has worked diligently with the Park Service to strike an agreement that would balance the conservation of natural values with the preservation of historically and culturally significant structures. Thanks in large part to this advocacy, and that of other stakeholders, the Park Service has added a new Yosemite Valley Historic Resources ORV that represents “a collection of river-related or river dependent, rare, unique or exemplary buildings and structures.”

While this is encouraging, our work is far from over. The draft Merced River Plan is expected to be released in early December and it will likely call for the removal of at least Sugar Pine Bridge, among other actions that would harm the Yosemite Valley Historic District.

The reason that the Park Service has proposed the removal of historic Merced River bridges is that their foundations are within the river’s natural channel, impeding free flow during periods of high water. But studies have identified many factors beyond the historic bridges that impact the Merced’s hydrology, and that the Park Service has a wide range of treatment options available that don’t require bridge demolition, including “bioengineering” techniques and better visitor management to avoid human trampling of riverbank vegetation.

The good news is that there is still time to make an impact on the bridges. The public is invited to participate in the 90-day period of review and comment for the Draft Merced River Plan/Environmental Impact Statement. Together, we are confident that a Park Service management plan can be realized for the Merced River that embraces, rather than endangers, these special bridges.

Please stay tuned to for updates on our effort and what you can do to help.

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National Trust for Historic Preservation

National Trust for Historic Preservation

The National Trust for Historic Preservation, a privately funded non-profit organization, works to save America's historic places.

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