Dredge #8 is also open for tours in Fairbanks, and the Pedro Dredge in Chicken is being readied for access. One such dredge, the Sixtymile Dredge, was moved in September 1999 from the Sixtymile gold district near Dawson to Skagway. Tourist-based operations with a gold dredge as the centrepiece. Several private attempts are being made in Alaska to develop There is a comprehensive paper on-line describing the process (see the Links page). 4, which is owned by Parks Canada, was found to have structural damage which required extensive emergency repairs to save the gantry structure. Preserving machinery the size of a gold dredge can present enormous technical problems.
Although they look complex, the basic concept is very simple - the buckets scoop up the gravel and dump it into sluice boxes inside the dredge, water is pumped in to separate the gold from the gravel, and the worthless gravel is then dumped out the back. Many changes and additions were made to make them suitable for working frozen ground, but the technology changed little for the 80 years they were in use.
The bucket-line dredges that changed the character of gold mining in Alaska and the Yukon were invented in New Zealand. With buckets that gouged out several cubic yards of gravel on each pass, enormous amounts of material could be processed by a dredge, so even fairly poor ground could be profitably mined. Relatively little gold was recovered, and it wasn't until the arrival of huge dredges that gold production soared. In fact, those methods were only used for testing streams, and in the early stages of mining in some areas such as the Klondike. Primarily done with gold pans, or possibly sluice boxes. Most people believe that gold mining in the Yukon and Alaska was Today the colossal hulks of gold dredges remain in many of Alaska's mining districts, and although they are now silent, they whisper of past glories.By Murray Lundberg Arctic & Northern Mining Walter Johnson deserves to be recognized for revolutionizing gold mining by creating machines that could do the work of a thousand men and find profit where before the ground was poor and impenetrable. After the Klondike-Alaska gold rush, much of the easy pickings were gone and primitive mining techniques were not enough to sustain the gold industry in Alaska. Over the next three decades the twin dredges collected over $600,000,000 in gold and small amounts of silver, and today they remain, largely unchanged, inside Yukon-Charley Rivers National Preserve. The dredge began operation in 1936, and the following year McRae purchased a second nearly identical dredge for nearby Woodchopper Creek.
At a cost of $156,000, McRae purchased a dredge from what was by that time called the Walter W. In 1935 the wealthy Canadian investor Alexander McRae was scouting locations for mining Alaskan gold on an industrial scale and after crisscrossing the territory, he selected a Yukon River tributary called Coal Creek where small-scale placer miners had been active for decades. Spence explains, even early dredges were considered a safe investment: Nevertheless, the Union Construction Company and other dredge-makers had discovered a winning strategy. Unlike the dredges Johnson designed for the tropics, the Alaskan machines faced cold and ice that curtailed the months they could operate and demanded that permanently frozen ground be thawed before it could be worked. The parts were then transported to a specific gold claim and reassembled. The dredges the Union Construction Company produced were built in San Francisco and then dismantled and shipped in pieces to Alaska. And in the early years he brought his family-his wife Pearl and sons Keith and Paul-on these work trips that took them on lengthy Yukon River steamboat journeys and to some of Alaska's most remote mining districts. Starting in 1909, Johnson began traveling to Alaska to direct the construction of dredges near Nome and throughout the Seward Peninsula as well as in the Alaskan interior at Ruby, McGrath, Iditarod, Circle, and Fairbanks.