Photo taken by Cowgirl Jules
License: Creative Commons Attribution-NonCommercial (CC BY-NC)
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BH Photo #279936
This is interesting. I saw the bridge before, and after the center collapsed. My inspection found a large section of a tree broadside to the center bents. This caused the water flow to go around the tree, a erode the bank. This erosion caused a bend foundation to fail, thus causing the center of the bridge to collapses.
All of West Side Lumber Company’s trestles were called bridges.
FYI, the historic 100-year flood in 1997 did NOT take down the middle section of Bourland Trestle. It was the 1998 earthquake in the Markleeville area that did it in. It's a common mistake that the Big Flood wiped out that section.
Sharon (Central Sierra historian)