Yankee Fork Gold Dredge

Gold was found on the Yankee Fork of the Salmon in the 1870s, and by the 1880s the camps of Bonanza and Custer were booming on the lode mines above them. By 1911 both were ghost towns. The gold left behind lay scattered through the gravels of the valley floor, too thin to pan and too deep to shovel, and in 1939 the Silas Mason Company decided to go after it with a dredge.

It came in pieces and was assembled on the spot: a barge 112 feet long, 54 feet wide and 64 feet high, weighing 988 tons, driven by two diesel engines. Crews flooded a pond, floated it, and set it digging. A chain of buckets on the bow scooped up the stream bed, the machine washed the gold out inside, and the stern dropped the stripped rock behind it, so that the dredge moved forward in its own pond. It ran around the clock, and people in the valley said they noticed its pounding only when it stopped. Between 1940 and 1952, with a pause for the war, it worked five and a half miles up the valley, handled 6.3 million cubic yards of gravel, and recovered about $1.04 million in gold and silver, at a cost of about $1.08 million.

What it left is plain from the road: long ridges of washed cobbles where a stream and its meadows used to be. Its last owner, J. R. Simplot, gave the dredge to the Forest Service, and an association founded by former crew members and their families restored it. It sits in its final pond between Bonanza and Custer, and volunteers lead tours through it in summer. It is part of Land of the Yankee Fork State Park, whose interpretive center is at Challis.