{"nrhp_refnum":"71000208","name":"Gold Dredge","other_names":["Tuolumne Gold Dredging Company Dredge"],"category":"structure","location":{"address":"S of La Grange","address_restricted":false,"city":"La Grange","county":"Stanislaus County","state":"CA","lat":37.63326014100005,"lon":-120.47742878199995,"geom_source":"nps_gis"},"listed_date":"1971-12-16","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry","Other"],"significance_levels":["local"],"summary":{"what_it_is":"A 1930s gold dredge near La Grange in Stanislaus County, California, built in 1937 for the Tuolumne Gold Dredging Company to a design by engineer Walter W. Johnson of San Francisco. It sits in the pond it dug as it worked.","why_significant":"The nomination presents the dredge as a significant remnant of the last days of the California gold rush and of the worldwide gold dredging industry. It stands amid landscapes altered by a century of mining, from hand mining through hydraulic mining to mechanized dredging. It is also tied to the region's \"southern mine\" heritage and to early large-scale electric power use by an irrigation district.","narrative":"Gold dredging left its mark on the Tuolumne River country near La Grange, and this dredge is one of its surviving machines. Built in 1937 for the Tuolumne Gold Dredging Company to a design by engineer Walter W. Johnson, it displaced about 3,600 tons and dug to a depth of 75 feet with a 92-ton bucket chain. It carried its own pond, digging ahead and leaving tailings behind, and it processed gold-bearing gravel inside through a revolving trommel before mercury was used to extract the gold. It capsized about a year into operation, was righted, and worked until 1949. The nomination values it as a remnant of the last phase of the California gold rush and of the worldwide dredging industry, set among hydraulic mining scars, ditch remnants and tailing piles. The dredge is two stories high plus a control house, and is mainly intact though neglected. Local proposals to turn it into a museum lacked funds.","period_of_significance":"20th Century","architect_builder":"Designed by engineer Walter W. Johnson of San Francisco; built for the Tuolumne Gold Dredging Company","architectural_style":null,"criteria":[],"status_note":"Described as two stories high plus a control house, mainly intact though neglected. Condition is marked fair, and the property is marked unoccupied. Talk of making it a museum has lacked local funding.","vacant_flag":true,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:55:32.018718-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_CA/71000208.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/71000208/55e8360734-800.webp","url_1600":"https://nationalhistoricalregister.com/media/71000208/55e8360734-1600.webp","licence":"CC BY-SA 4.0","author":"Newmanhouse2004","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Tuolumne_Gold_Dredge_2017_La_Grange_California.jpg\" rel=\"noopener\">Newmanhouse2004</a>, <a href=\"https://creativecommons.org/licenses/by-sa/4.0\" rel=\"license noopener\">CC BY-SA 4.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Tuolumne_Gold_Dredge_2017_La_Grange_California.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/123862156","wikipedia":"https://en.wikipedia.org/wiki/Gold_Dredge","wikidata":"https://www.wikidata.org/wiki/Q65059422"},"indexable":true,"url":"https://nationalhistoricalregister.com/california/stanislaus-county/gold-dredge-71000208/"}