|This article is in need of a Photo.To add an image to this page, click "Edit" and then click the "Files" button.|
|Yuba County as a gold producer stood first in the State for many years and still commands a leading position. In 1936 it showed a marked increase over 1935, the production being 81,358 fine ounces of gold worth $2,847,530 this gold being produced by eight lode and sixteen placer mines. In this same year Yuba County produced 4,468 fine ounces of silver worth $3,460 the above being the report of the Bureau of Mines and excludes itinerant prospectors, etc. In Yuba County, about seven miles east of Marysville is the largest gold dredger in the world; it cost about $750,000 and its bucket line digs 120 feet from the surface of the water, which latter is about 15 feet below the natural surface of the ground. During the 33 years of gold dredging in that field a total of twenty-one dredgers have operated, producing about $75,000,000 in gold and this Company has still proven up ground to operate on which it will take about another 25 years to cover. The area mined and to be mined is about 95 per cent, being land, mainly used for grazing purposes, with very low assessement values.|
The Gold Rush changed California in many ways. California's population expanded tremendously and became more diverse due to the miners arriving from faraway parts of the world, but Nisenan people were attacked and pushed off their lands. Towns rose and grew throughout California, while steamships and railroads provided new methods of transportation. The influx of new residents helped lead to large-scale agriculture becoming established in the central valley for the first time, but some of the new mining techniques destroyed mountainsides and ecosystems and dumped so much debris into rivers that the riverbeds rose and the rivers began flooding the new farmlands in the valley.
At first, individual miners used simple panning techniques to find gold. This was a form of placer mining. However, panning cannot be done on a large scale, so many miners soon progressed to using placer mining "cradles," "rockers," and "long-toms" to process larger volumes of gravel. In the most complex form of placer mining, groups of miners would divert the water from an entire river into a sluice alongside the river, and then dig for gold in the newly-exposed river bottom. The U.S. Geological Survey estimates that some 12 million ounces of gold (worth approximately $7,000,000,000 in today's prices) were mined during the first five years of the Gold Rush.
By 1853, it was becoming more and more difficult for individuals with pans, cradles, rockers, or the like to find any remaining gold. Instead, corporations developed hydraulic mining techniques to extract gold from gravel beds on hillsides and bluffs. A high-pressure hose directed a powerful stream or jet of water at the gravel beds, loosening the gravel. Then the gravel and gold were passed over sluices, with the gold settling to the bottom, where it was collected. This process was used in Yuba County at Camptonville and Strawberry Valley, as well as in other counties upstream, such as at Malakoff Diggins State Historic Park. The resulting exposed earth and gravel deposits are unable to support plant life to this day, due to the heavy metals and other pollutants dredged up and artificially concentrated during the hydraulic mining process. Only after a thorough environmental cleanup can these sites be revegetated.
Another problem with the hydraulic mining process was that the gravel and silt that were separated from the gold during the hydraulic mining process fell into creeks and rivers, raising the riverbeds. The bed of the Yuba River was raised so high that the river spilled out into a two-miles-wide, 20-feet-deep flow that overran hundreds of thousands of acres of orchards and pastures and (repeatedly from the late 1860s, and especially in 1875) buried the entire city of Marysville and much of what is now Yuba City in as much as 25 feet of muck. The bed of the Feather River was also raised substantially, which caused it to flood Sacramento repeatedly and has rendered it unnavigable, except by very small boats, to this day.
Mining law in California was initially quite localized and relied on decisions of the mining towns' inhabitants. The inhabitants of the mining towns cared more about their own ability to mine for gold than about downstream residents' ability not to be buried in 25 feet of muck, so they chose to continue hydraulic mining regardless of the damage caused downstream. In 1868, angry farmers in Marysville and what would later become Yuba City formed the Anti-Debris Association, which filed a lawsuit against the wealthy mining companies upstream. In 1875, the association won its lawsuit. As a result of this decision, a dam 11,000 feet long (nearly two miles) was built in 1880, about nine miles upstream from Marysville, to re-confine the Yuba River to a narrower bed. The dam was built of brush, wire, and logs, and cost approximately $100,000. Later attempts to reduce the problem included a massive system of Levees and in 1895, the installation of the Marysville River Pumps. But flooding on a smaller scale has remained a problem in much of the area to this day.
Corporations also developed a new technique called hard-rock mining, which ended up being the most lucrative of all the mining techniques used in California: extracting gold that was embedded in solid rock (typically quartz) and therefore could not be extracted through other techniques. Companies engaged in hard-rock mining used dynamite to blast through hillsides, following veins of the gold-bearing quartz. The gold-bearing rocks blasted apart in this way were crushed, and the gold was either separated out with moving water or, in more difficult cases, leached out with arsenic or mercury. This process further contaminated the environment, leaving arsenic and mercury to seep into the soil, which again has made it impossible for plants to grow in these areas to this day, except where thorough environmental cleanup has been performed.
Although the Gold Rush is considered to have ended in 1855, many gold recovery operations continued for decades after that. The final stage of corporate gold mining efforts was to dredge downstream debris for any gold that had washed down into the flat river bottoms and sandbars of the central valley. By the late 1890s, Wendell P. Hammon had developed new dredging technology that is companies used to dredge more than 20 million ounces of gold (worth approximately $12,000,000,000 in today's prices) from the valley. Piles of gravel dredged from the Feather River for this purpose can be seen from Highway 70 near Oroville. The company dredger towns of Hammonton and Marigold were founded exclusively to house and provide for the dredging companies' employees. In the mid-20th century, when so much of the gold had been successfully dredged that continued dredging was no longer profitable, the companies shut down the towns and displaced the residents.