Potential San Francisco Bay Landslides During El Niño

1996-97 Rainy Season

Debris Flow,
Sierra Nevada
North Fork of the Stanislaus River
(computer simulation)

    This computer simulation depicts the Sourgrass debris flow (Sierra Nevada, North Fork of the Stanislaus River), of January 1, 1997. The flow was 2.4 miles long, with a vertical drop of 2,000 feet. The first half moved 2 to 3 miles per hour, which is roughly the speed of a fast walk. The second half accelerated to 12 miles per hour, or the speed of a runner doing a 5 minute mile.

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Views of Debris

    Close-up view of debris flow, consisting mainly of fallen trees along part of the lower flowpath.

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Photo courtesy of Jerome V. DeGraff, U.S. Forest Service

    Close-up view across the North Fork of the Stanislaus River, of woody debris remnants of debris flow deposit. Note the people standing in the center for scale.

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Photo courtesy of Jerome V. DeGraff, U.S. Forest Service

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