{"nrhp_refnum":"75000173","name":"Barker Dam","other_names":[],"category":"structure","location":{"address":"SE of Twentynine Palms in Joshua Tree National Monument","address_restricted":false,"city":"Twentynine Palms","county":"Riverside County","state":"CA","lat":34.03118215650005,"lon":-116.14495966221745,"geom_source":"nps_gis"},"listed_date":"1975-10-29","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Agriculture"],"significance_levels":["local"],"summary":{"what_it_is":"A cement and stone-faced cattle watering dam about 150 feet long in Joshua Tree National Monument, southwest of Twentynine Palms, Riverside County, California. It was built in 1900 by cattleman C.O. Barker and later raised by William F. Keys.","why_significant":"The nomination argues local significance under agriculture. The dam is typical of structures built by cattlemen in arid desert regions to capture rainwater from infrequent cloudbursts for livestock. It served a number of cattlemen over the years, and its use of cement and local rock reflects the rocky terrain, where earthwork dams were less practical.","narrative":"Barker Dam is a stock-watering dam in what is now Joshua Tree National Monument, southwest of Twentynine Palms. Local cattleman C.O. Barker built it in 1900 from cement faced with native stone, standing about nine feet high. Construction required sixteen eight-day trips to haul cement, wooden forms, mixing equipment and other materials from Banning. After 1917, at an unknown date, cattleman William F. Keys obtained the dam and added three feet of concrete, bringing it to twelve feet and increasing the water it could hold. The structure runs about 150 feet and has several indentations in its design. A low dry-stone wall above it kept livestock out of the deeper water, and a pipe feeds a pond of two concentric circular walls below. The dam is considered locally significant in agriculture as a typical example of the structures cattlemen built to capture desert cloudburst runoff, using cement and local rock rather than earth.","period_of_significance":"1900-present","architect_builder":"C.O. Barker; W.F. Keys","architectural_style":null,"criteria":[],"status_note":"Described as in excellent condition and unaltered at its original site; still serviceable and listed as unoccupied, with present use as park.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:55:31.463606-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_CA/75000173.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/75000173/dc45089473-800.webp","url_1600":"https://nationalhistoricalregister.com/media/75000173/dc45089473-1600.webp","licence":"Public domain","author":"Robb Hannawacker, while working for Joshua Tree National Park","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Barker_Dam_from_below_-_12525231923.jpg\" rel=\"noopener\">Robb Hannawacker, while working for Joshua Tree National Park</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Barker_Dam_from_below_-_12525231923.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/123860439","wikipedia":"https://en.wikipedia.org/wiki/Barker_Dam_(California)","wikidata":"https://www.wikidata.org/wiki/Q4860949"},"indexable":true,"url":"https://nationalhistoricalregister.com/california/riverside-county/barker-dam-75000173/"}