The last of the Dredges to work in the Sumpter Valley is now an Oregon State Park and is open to tours throughout the summer. and we have about 200 acres of these tailings at the Rock Bottom Ranch!īelow is an aerial view of the tailings as the dredges worked back and forth across the valley. Workers referred to the rock piles the dredge left behind as tailings because the end of the dredging process used a conveyor called a “stacker arm” which deposited unwanted rocks behind the dredge as it was digging ahead of itself. The Sumpter Valley now has approx. The Sumpter Dredges were floating mechanized placer operations – therefore, most of the rocks that we see today, were processed by the dredges, then returned to the valley in the form of tailings or rock piles. That is 128,570 troy ounces which, at the recent value of $1,400.00 per ounce, would be worth $180,000,000.Photos courtesy of the Baker County Library In its lifetime this dredge made $4.5 million at $35 per troy ounce. The last dredge closed in 1954, more than $100,000 in debt.

Still, it cost more to run than the gold could pay for. Between them, the dredges traveled more than 8 miles (13 km), extracting $10 to 12 million worth of gold. 3 was built substantially from parts of the first dredge, which had been idle for 10 years. Three dredges worked the valley from 1913 to 1954. Dredge workers often reported hearing the ghost of Joe Bush 'Haunting' the dredge when the dredge was not operating due to closure or repair. One or two men had to stay on board to watch over the machine during the evenings. The dredge operated 363 days a year most of the men were given the Fourth of July and Christmas day off from work. The Sumpter Valley Gold Dredge required a three-man crew to operate the machinery and 17 more workers to complete the crew for maintenance, bookkeeping, surveying, truck driving, managing and a few other roles. The dredge that was built in Sumpter Valley could dig over 20 buckets per minute, consuming more than seven yards of earth each minute. The primary advantages that made the dredge more efficient than other methods were the volume of earth it could process and having its own water supply. In essence, the dirt that was dug by the large electrically powered buckets was sifted and sorted, and the remainder was washed over a series of riffles allowing the gold to settle and be trapped. The internal mechanics were not very sophisticated-they duplicated, on a larger scale, many of the devices used by placer mining throughout the gold rush, such as the gold pan and the sluice box.

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