Sierra Foothills

Mokelumne River Watershed Dry Creek Watershed Cosumnes River Watershed American River Watershed North Fork American River Watershed

The Sierra Foothills have a beautiful pastoral landscape of oak woodlands, grazing lands, orchards and vineyards, river canyons and creeks. This was not the view 165 years ago. The foothills have recovered significantly from the ravages of the gold rush through both natural restorative processes and the work of farmers and ranchers.

When miners first started looking for gold they used simple techniques for sorting river gravels with a metal pan or a rocker or long tom. Several cubic yards of river gravels could be sorted per day this way. Between 1848-1853 about 10-12 million ounces of gold were produced. Nearly every alluvial creek channel was dewatered, sorted for gold and left; today many waterways show the remnants of this mining. In 1853 gold mining changed significantly. Instead of indivduals or small groups of miners, investment companies using expensive equipment started mining using large volumes of water. Termed hydraulic mining, large monitors or hoses were aimed at hillsides and washed away the sediment so it could be sorted and the gold in the ancient riverbeds could be mined. Many hundreds of cubic yards of sediments could be processed in a few hours. Water had to be developed and transported through ditches or canals to the mining site. By 1865 5,000 miles of ditches and flumes had been constructed to move water to the hydraulic mines. Between 1853 and 1884 over 11 million ounces of gold were produced using hydraulic mining. 

To collect the gold flecks in the gravels and wash water the miners added mercury or quicksilver. Mercury has a natural attraction to gold and will amalgamate the small flecks into larger amalgams which are then heated to remove the mercury.  Mercury was mined in the coastal ranges of California in places like New Almaden (Santa Clara County), New Idria (San Benito County) and many mines in Lake, Napa and Sonoma Counties. The mining and processing of quicksilver in furnaces as well as its use in the gold fields has left a major toxic legacy. Nearly every stream and reservoir in the Sierras has remnant mercury in its sediments.

Hydraulic mining left another legacy. The destruction of numerous mountainsides washed millions of yards of sediment into Central Valley rivers and the San Francisco Bay filling channels and affecting adjacent farmland. The flood of 1877-78 inundated many cities and farms and initiated a series of lawsuits between downstream owners and the mining companies. In 1884 Judge Sawyer outlawed hydraulic mining in the Yuba River and the practice stopped in the state. 

The next focus of the gold mining companies were the valley rivers and floodplains. These areas had fine sediments with highly distributed gold deposits. The miners dredged these areas and could profit if the sediment contained only $0.10-0.15 cents of gold per cubic yard of sediment. Beginning in 1898 the Feather River was dredged with thousands of cubic yards processed per day and over 20 million ounces of gold produced.

Despite all the efforts at removing gold from hillsides, rivers, creeks and floodplains the greatest amount of gold was produced from hard rock mining of quartz veins. Quartz is very hard rock and once removed from the earth has to be crushed in a stamp mill. Then the crushed rock was mixed with mercury to amalgamate the gold. Hard rock mining began in Mariposa County in 1849 and many Sierra mines operated until the late 1940s. Over 60% of the gold in the foothills was produced from hard rock mines. Eight of these mines had a total production of over 1,000,000 ounces of gold.

The American River watershed is made up of three major waterways, the North, Middle and South Forks. James Marshall’s discovery of gold occurred on the South Fork in the town of Coloma. Placerville near the South Fork was established in 1854 and originally was called Hangtown, a mining camp started in 1848. Both Leland Stanford and Mark Hopkins were involved in the development of Placerville before their investment in the Central Pacific Railroad with Charles Crocker and Collis Huntington completed the intercontinental railroad. Georgetown near the Middle Fork started in 1849 by George Phipps and was originally named Growlersberg after the growling sounds of quartz/gold rocks in miner’s pockets. Auburn near the North and Middle Forks grew from the Woods Dry Diggings in 1849 and was destroyed by fire in 1855, 57 and 63 and rebuilt.

Near the Cosumnes River Fiddletown was settled by a group of Missourians as a trading center and mining camp. It gained its name from the dry summer streams when placer miners could not work and were just “fiddling around”. A Chinese community of 2000 lived in Fiddletown by 1860. 

Dry Creek in Amador County was the home of gold rush towns Volcano, Amador City, Sutter Creek and Jackson. Volcano is located in a bowl-shaped valley mistaken for a volcano by early miners in 1848. By 1852 there were 300 houses and hydraulic mining started in 1855. Amador City was named for Jose Amador who mined along Dry Creek. The hard rock Keystone Mine operated here between 1853 and 1942 and produced over $24 million in gold. Beginning in 1848 Jackson was a major stopping place between Sacramento and the mines in the southern Sierras. Placer mining in this area was over by 1869 and the hard rock Kennedy mine began operating. Overtime the tunnels of this mine reached 5,912 feet below ground making it the deepest mine in North America with over 150 miles of tunnels. The invention of the steam-powered drill and dynamite allowed for the great depths of excavation in this mine. Sutter Creek was named for John Sutter who logged in the area. The town began in 1854 and supported the Central Eureka Mine which reached a depth of 2300 feet by 1932.

The Mokelumne River watershed was home to the town of Mokelumne Hill in 1848 which had very rich placer mining. Mokelumne Hill was known for it lawlessness and gambling and in 1851 had one homicide a week for 17 weeks. Famous bandit Joaquin Murrieta was a frequent visitor to the gambling halls.

Just to the south in the Stanislaus River watershed the town of Columbia established in 1850 added 5,000 new residents in several weeks after gold was discovered. The town had 8 hotels, 4 banks, 17 general stores, 2 firehouses, 2 bookstores, 1 newspaper, 3 churches and over 40 saloons. By 1860 most of the gold was gone except for in the sediments underneath the town. So, the miners tore down the town to get the remaining gold. From 1850 to 1900 over $150 million in gold was removed.

By the end of the placer and hydraulic mining era the landscape of the foothills, valley rivers and northern San Francisco Bay were permanently altered.

Large scale water development accompanied hydraulic mining to bring water from higher altitude reservoirs into the foothills. In the Georgetown area the California Water Company developed 300 miles of ditches, flumes and pipes. The Natomas Ditch near Salmon Falls in the Folsom area was 16 miles long, 8 feet wide and 3 feet deep. Many of these ditches were abandoned between 1950-80 in favor of pipelines, but there are still many in use such as the El Dorado, Coloma-Lotus Ranch and Goldhill and Farmers Ditches. This infrastructure provided water to foothill farmers and ranchers and eventually urban areas.

Many of the farms and ranches in the Fish Friendly Farming program show the scars from the gold rush. Topsoil was imported to make the land productive again. A diversity of agricultural and ranching operations has helped to recover the productivity of the land and allowed native landscapes to re-establish. However as is so obvious in locations such as the Malakoff Diggings State Park and the widespread occurrence of toxic mercury the legacy of the gold rush remains and will be with us for many decades.