Yuba Goldfields
The Yuba Goldfields is a valley of 10,000 acres (40 km2) on both sides of the Yuba River in Yuba County, California, located northeast of Marysville. The goldfields are noted for their otherworldly appearance, filled with oddly shaped gravel mountains, ravines, streams and turquoise-colored pools of water. From the air, the goldfields are said to resemble intestines.
Wild turkeys, deer, ducks, Beavers, herons, bald eagles, Northern river otters and even mountain lions now call the goldfields home.
They were created during the California Gold Rush. The first Yuba-area miners panned for gold in stream beds in the valley but within a decade large-scale industrial processes replaced solitary prospectors. Mining companies moved from the valley floor into the Sierra Nevada foothills, where miners blasted gravel hillsides with high-pressure jets of water—a process called hydraulic mining. After the miners extracted gold in long wooden sluices, they dumped the gravel back into the mountain valleys. Rivers and streams carried the flood of sediment—called slickens—down to the Sacramento Valley. Anywhere between 326,000,000 cubic feet (9,200,000 m3) to 685,000,000 cu ft (19,400,000 m3) of debris was deposited in the Yuba River. The mine waste carried by the Yuba River ended up raising the riverbed (by up to 100 feet (30 m) in some cases), causing floods that buried farms east of the town of Marysville with gravel, mud, as well as mercury and arsenic (byproducts of the mining process). As the Yuba River is a tributary of the Sacramento River, much of that debris then found its way to the San Francisco Bay. In Sacramento, the I Street Bridge had to be raised twenty feet (6 m).Lawsuits by farmers curtailed hydraulic mining in 1883, but the gravel remained behind in the Yuba Goldfields.
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