{"nrhp_refnum":"00000344","name":"Sloat's Dam and Mill Pond","other_names":[],"category":"structure","location":{"address":"Off of Station Rd.","address_restricted":false,"city":"Sloatsburg","county":"Rockland County","state":"NY","lat":41.15796252450005,"lon":-74.18908099601792,"geom_source":"nps_gis"},"listed_date":"2000-04-06","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Commerce","Community Planning and Development"],"significance_levels":["local"],"summary":{"what_it_is":"A historic hydropower complex on the Ramapo River in the village of Sloatsburg, Rockland County, New York, with a dam begun about 1792, a sluice gate, raceway, mill pond and remnants of an estate entrance, now within a county park.","why_significant":"The nomination argues it is the sole surviving remnant of Sloatsburg's industrial center and the only intact one of three early hydropower systems in the area. Its dam, sluice, race and pond powered mills from the 1790s until 1955. It is listed under Criteria A and C for engineering, commerce and community development.","narrative":"Sloat's Dam and Mill Pond is a surviving piece of the hydropower system that once drove the mills of Sloatsburg, in Rockland County, New York. Isaac Sloat built the first dam across the Ramapo River around 1792 to power a sawmill and tannery. His son Jacob later added a textile mill, and later owners made silk and finished textiles there until a fire destroyed the last mill in 1955. The site now includes the roughly 200-foot dam, strengthened with concrete and cobblestone end walls, along with a sluice gate, a raceway and the pond. Two cobblestone gateposts and stone walls from the former Brown Estate entrance also stand within the boundary. Two other early dams in the area were washed out or damaged by floods, leaving this system as the only one largely intact. It was listed for its engineering, commercial and community development importance, and local groups hope to turn it into a historical park.","period_of_significance":"ca.1792-1949","architect_builder":null,"architectural_style":null,"criteria":["A","C"],"status_note":"The mills burned in 1955 and were demolished in 1966. The dam, sluice, race and pond survive within an undeveloped county park, with the features described as abandoned for nearly half a century.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:51:50.219101-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/00000344.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/00000344/81d1b2a739-800.webp","url_1600":"https://nationalhistoricalregister.com/media/00000344/81d1b2a739-1600.webp","licence":"CC BY-SA 3.0","author":"Daniel Case","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Sloat%27s_Dam_and_Mill_Pond_2.jpg\" rel=\"noopener\">Daniel Case</a>, <a href=\"http://creativecommons.org/licenses/by-sa/3.0/\" rel=\"license noopener\">CC BY-SA 3.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Sloat%27s_Dam_and_Mill_Pond_2.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75321506","wikipedia":"https://en.wikipedia.org/wiki/Sloat%27s_Dam_and_Mill_Pond","wikidata":"https://www.wikidata.org/wiki/Q777340"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/rockland-county/sloats-dam-and-mill-pond-00000344/"}