Downstream (above) and upstream views of Greenhorn Creek from Red Dog Road
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THE PHOTOS TO THE LEFT show one legacy of hydraulic gold mining in the Greenhorn Creek watershed. Millions of cubic yards of gold-bearing “auriferous” gravels were power-washed from the late 1850s until 1884 in nearby mine sites such as Sailor Flat, Buckeye, Boston and Red Dog. The sedimentary gravels are now piled up to 40 feet high on the banks of the creek, but they once lay undisturbed for millions of years. They were deposited during tens of thousands of flood events during the Eocene Epoch (56-34 million years ago) in channels of an ancient Yuba River.
Standing here on the morning of Feb. 27, I could continually hear gravels crumbling away from these embankments — sometimes just a rock or two, and sometimes larger amounts of loose rock. The processes of erosion are usually so slow, you typically can’t hear or see it happening. Here, it moves quickly. Everything about hydraulic mining sped up natural processes.
Although the layers of gravel here look similar to the cemented sedimentary gravel walls of hydraulic diggings in nearby Red Dog and You Bet, these gravels washed here from their ancient Yuba channels somewhere upstream. The top of the gravel embankments were once the high point of mining debris fill-in and the creek must have flowed close to this level before eroding back down to its present depth. Once wonders how much deeper the gravels continue below the creek.
This area can be accessed from the north via Red Dog Road out of Nevada City, and from the south via You Bet and Red Dog roads. The route from the south is only drivable with high-clearance and 4WD vehicles. Needless to say, it’s dangerous to stand anywhere near the edge of the embankments.
The Boston Hydraulic Gold Mine in Red Dog, circa 1879. This mine was located east of Red Dog, about a quarter-mile from Greenhorn Creek and the location of the above photos. The photo was created by renowned San Francisco photographer Carleton E. Watkins who was touring the Northern Mines as a commercial photographer. He aimed to promote modern industrial mining methods and man’s technological conquest of nature in the pursuit of gold. (Photo from the collection of the Bancroft Library, University of California, Berkeley)
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