Ground its Way Through River Valley
By Steve Lent, Crook County Historian
Gold was discovered in Sumpter, Oregon in 1862. A rush to the area soon led to major mining activity. The rush significantly diminished by the early 1900s. Miners knew that flakes of gold remained buried in the Powder River valley river bed. It was deemed impossible to extract the gold by hand so a dredge was designed to mechanically help.
Dredges had been used to level or deepen waterways and seemed well suited for large scale gold mining operations. A dredge offered a high yield and low operating costs and made a promising investment for prospectors.
Three dredges were built in Sumpter Valley in 1912, 1915 and 1935. Each dredge had the same design. A long row of front buckets that dug though the ground and steadily dumped debris into the sledge. There were 72 buckets with each one weighing one ton. The earth passed through a series of sorting mechanisms in the interior of the dredge that sifted out the flakes of gold. The left over dirt and rocks, known as tailings, were dumped behind the dredge. The dredge could scoop up to 280,000 cubic yards per month. The dredge could operate with a three man crew per shift for 24 hours. The dredge operated 363 days a year.
The dredges were assembled on the Powder River but were not bound to the river. Their floating design allowed them to strike out perpendicularly into the old river bed. The dredge had a shallow hull and operations allowed it to move a pond with it as it progressed along the old stream bed. As the buckets cut new channels in the earth river water would flow forward into the new channels, keeping the dredge afloat and moving forward.
The two early dredges were discontinued and disassembled in the 1920s. The 1935 dredge was constructed using parts from the earlier dredges. It continued to operate until the early 1950s when local concerns on environmental issues and skyrocketing operating costs led to operations ceasing in 1954. The three dredges had worked the valley from 1913 to 1954. They had traveled more than 8 miles and extracted $10 to $12 million worth of gold.
The 1935 dredge remained after it was abandoned and began to deteriorate. In the early 1990s locals developed an interest in preserving the dredge as a reminder of local history. Enthusiasm created an interest by Oregon State Parks and led to the establishment of the Sumpter Valley Dredge State Heritage Area. The dredge and surrounding area were preserved and opened to the public in 1994.