Some large and profitable mines operated in the early 1900s at Happy Camp, Calif., on the Klamath River.
The Van Bruant, the Richardson and the Siskiyou were three of the largest hydraulic mines. The Richardson reportedly earned about $150,000 in gold, frequently at a rate of $1,000 a day.
In 1915, the Siskiyou Mines Co. of New York City worked 1,500 acres on the Klamath River, including several old placer claims, which had only been superficially exploited by earlier miners. Water was carried from Thompson Creek in a three-mile ditch and 10-mile flume. The mine had the wood for the flumes milled locally, and mules hauled in all piping and other equipment.
The Van Bruant Mine was one of the largest hydraulic operations in Northern California. It washed gravel from all directions into a tunnel in the center of the mine, discharging the gravel through a flume to a dumpsite.
Chinese workers ran or owned a number of hydraulic and placer mines, including the Muck-a-Much Mine. They transported water to the mine through a pipeline suspended across the Klamath River.
Sources: "Chapters of State Mineralogist’s Report (Biennial Period 1913-1914)." Report XIV, Of the State Mineralogist: Mines and Mineral Resources of Siskiyou County Of Portions of California. Print; Gryder, J.B. "Gold Mining from Scott Bar to Happy Camp." Siskiyou Pioneer Vol. II.10 (1957): 27-35. Print.