{"nrhp_refnum":"89001942","name":"Mechanicville Hydroelectric Plant","other_names":[],"category":"district","location":{"address":"At NY 32 on Hudson River","address_restricted":false,"city":"Mechanicville","county":"Rensselaer County","state":"NY","lat":42.878083933000056,"lon":-73.67929792610471,"geom_source":"nps_gis"},"listed_date":"1989-11-13","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry","Engineering","Architecture"],"significance_levels":["state"],"summary":{"what_it_is":"A hydroelectric power plant on the Hudson River near Mechanicville, on the Saratoga County side with a dam section reaching Rensselaer County, built in 1897-98 by the Hudson River Power Transmission Company. It includes a brick powerhouse, an earth embankment, a non-overflow dam and an overflow dam.","why_significant":"The nomination argues the plant is the oldest extant hydroelectric plant in New York State in continuous use since 1897. It is an outstanding example of large-scale industrial architecture of the early hydroelectric industry and an intact example of sophisticated generation engineering. Its powerhouse, dam and machinery are among the earliest remaining in the nation.","narrative":"Mechanicville Hydroelectric Plant sits on the Hudson River south of Mechanicville, New York. Built in 1897-98 by the Hudson River Power Transmission Company, it combines a brick, gable-roofed powerhouse with an earth embankment, a concrete non-overflow dam and a long concrete overflow dam running to the eastern bank. Inside, seven General Electric generators, original to the 1897-99 installation, are driven by turbines that were replaced in 1902 with larger units by S. Morgan Smith. The plant was designed to send alternating current to customers including the General Electric works at Schenectady, at a time when long-distance transmission was a new technology. It has operated continuously since construction and is described as the oldest extant hydroelectric plant in the state. The nomination values it for industrial development, engineering and architecture, noting that the building and equipment remain remarkably close to their original appearance. Later additions include a 1901 boiler house and 1950s frequency converters.","period_of_significance":"1897, 1902","architect_builder":"A.C. Rice, Engineer/Architect; Stillwell-Bierce and Smith-Vaile, Builder","architectural_style":"Industrial, Queen Anne","criteria":["A","C"],"status_note":"Still operating as a hydroelectric power plant; the concrete of the western abutment and waste gates on Bluff Island is severely deteriorated (1989).","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:50:45.962131-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/89001942.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/89001942/31829e18f2-800.webp","url_1600":"https://nationalhistoricalregister.com/media/89001942/31829e18f2-1600.webp","licence":"Public domain","author":"The Street Railway Journal (1898)","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Mechanicville_Hydroelectric_Plant.jpg\" rel=\"noopener\">The Street Railway Journal (1898)</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Mechanicville_Hydroelectric_Plant.jpg"},"district":{"nrhp_refnum":"14000860","name":"New York State Barge Canal","url":"https://nationalhistoricalregister.com/districts/new-york/new-york-state-barge-canal-14000860/"},"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75321256","wikipedia":"https://en.wikipedia.org/wiki/Mechanicville_Hydroelectric_Plant","wikidata":"https://www.wikidata.org/wiki/Q14706930"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/rensselaer-county/mechanicville-hydroelectric-plant-89001942/"}