Sumpter Valley Dredge
Sumpter Valley Dredges
When speaking about a dredge, the question that arises most is, "What is a dredge?"
There are dredges which are used to maintain the depth of a river's channel so that ships can pass and/or to improve harbors. And then there is the paddock dredge, invented in New Zealand, which is floated on pontoons or a hull. Some people see that type as a monster that looks like a praying mantis, destroys the land and reflects the greed of man. Now some of that may be true, but a paddock dredge is simply a machine, similar to a combine used for harvesting wheat, or a potato digger working in the field. Like potatoes dug from the ground, a gold dredge also digs and pulls the gold bearing earth up into it's belly to be processed, keeping the gold and spewing the waste out the back by way of a stacker. Built on pontoons or a shallow hull, these dredges could be used in a pond or small river. They did not need a lot of water, as they moved their pond with them.
The dredges that affected the Sumpter Valley certainly may have been created because of greed. In the history of man, his search for wealth has been a prolonged venture, and gold definitely has played a big part. Any and all imaginable ways to get that gold out of the earth and into their pockets was attempted.
Late in the year of 1912, being assembled just south of the city of Sumpter (down stream of the S wye of the Sumpter Valley Railway Co.), the first Yuba-style dredge in the Sumpter Valley would soon start a trend. Built by the Powder River Gold Dredging Co., the hull was 100 feet long and 45 feet wide and was made entirely of wood. This dredge had 65 buckets, each holding nine cubic feet of earthen material which was dug at a rate of 21 buckets per minute (totaling an estimated 189 cubic feet or 7 yards per minute). Indeed, if the valley had never seen a monster before January 7, 1913, it certainly did that day.
Powered by an electric motor, the bucket line scooped up the earth and dumped it into a hopper which directed it into a trommel, a long tube that rotates with perforations in its entire shell. Here, the gold and small materials were to sift through the ¾-inch holes and fall into the sluice boxes. Gold bearing sand and water were flushed over a series of piffles where the gold settled and was trapped. The coarser material was carried up the stacker on a conveyor belt and deposited behind the dredge, leaving mountains of rock know as "tailings." This dredge was operated until July 23, 1924, but it was not alone.
In October of 1915, the Powder River Gold Dredging Co. started up their second dredge, known as the No. 2. Both dredges were built with the same size hull, yet there were some differences. For instance, No. 1 was made with wood sheathing while No. 2's superstructure was covered with flat steel siding painted gray. Powder River Gold Dredge No. 2's buckets carried only 7« cubic feet, while No. 1's carried 9. Both were powered by electricity, and both chewed up about 60 acres of ground per year. While No. 1 made its way south toward the town of Ewen, No. 2 was constructed upstream of the S wye and was busy on its hunt up McCully's Fork and Cracker Creek toward the town of Bourne. In 1923, Powder River Gold Dredge No. 2 digested its last meal of earth. It was dismantled (all but the hull, which still sits in a pond along the road to Bourne) and shipped to central Washington to be used and renamed the Liberty Dredge. On July 23rd of the following year, Powder River Gold Dredge No. 1 was also shut done and its hull rests in a pond across the grade from Sumpter Valley Railroad Restoration's McEwen Station in the Railroad Park. In 1934 when President Franklin D. Roosevelt raised the price of gold from $20.00 to $35.00 per troy ounce (12 oz. per lb.), the Sumpter Valley Dredging Company began the work to create a new and improved monster. Most dredges were built in a pit which was flooded after the hull was constructed. At the dredge shop area south of Sumpter, this dredge was built like a ship with the hull and steel framing constructed on shore. Then on April 16, 1935 the pins were pulled and it was launched with a splash. After the heavy machinery of Powder River Gold Dredging Co.'s No. 1, at McEwen, was relocated to the new dredge, the ladder was extended and the outer housing constructed. It began digging on June 26th of that same year.
The new and improved dredge was larger, it's hull being 125 feet long and 52 feet wide, running 72 buckets (upgraded to 10 cubic feet) at a speed of 25 buckets per minute, and chewing up 225 cubic feet (8.33 cubic yards) per minute — averaging an estimated 100 acres per year. This dredge was also electric powered and had a 250 horsepower motor. Until October of 1942, the dredge worked 24 hours per day, seven days a week, except Christmas and the Fourth of July. Then in October, 1942, all non-essential mining was ordered to halt for the duration of World War II. Germany surrendered in May of 1945, and dredging began again on July 5 of that year. Jigs were added, increasing the gold recovery to 93%.
It took over twenty men to keep a dredge going, including a superintendent, dredge master, bookkeeper, electrician, part-time surveyor, shop foreman, truck driver and two or three machinists, plus three people on shore crew and the nine who operated the dredge (3 shifts each with a winchman, head oiler and stern oiler).
The dredge was anchored in place with a spud (or counterweight)) and bow and stern lines connected to "deadmen"" (usually logs buried in the ground). Using winches aboard the dredge, it could be maneuvered to dig in any angle. With the bucket line digging ahead while the 96-foot stacker mounded the tailings behind, the dredge worked back and forth across the valley using the water from the Powder River.
The Sumpter Valley Dredge ceased operation in 1954 when the costs outweighed the profits. In its lifetime this dredge made 4.5 million dollars at $35.00 per troy ounce. That's 128,571.43 troy ounces which, compared to a more recent value of $400.00 per ounce, would equal $51,428,572.00. There are some who feel that there was a lot more gold found which just wasn't reported. (A creation for getting rich? More than likely.)
The dredge now can be viewed at the Sumpter Valley Dredge State Heritage Area in the same location where it was shut down in 1954. With the restoration of it begun in the summer of 1995, forty-one years after its use, its existence will be perpetuated for the visitors to this Oregon State Parks facility. There are dredges still operating in the world, but Sumpter Valley has seen it's last of the trio that changed what was once cattle pasture to very unique wetlands full of wildlife. Some say the dredges destroyed the valley, others disagree. Decide for yourself and enjoy your visit.
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Sumpter Valley Dredge State Heritage Area