{"nrhp_refnum":"89002269","name":"Wachusett Dam Historic District","other_names":[],"category":"district","location":{"address":"N end of Wachusett Reservoir at Lancaster Millpond","address_restricted":false,"city":"Clinton","county":"Worcester County","state":"MA","lat":42.39952050000005,"lon":-71.70571351177685,"geom_source":"nps_gis"},"listed_date":"1990-01-18","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Community Planning and Development","Engineering","Politics/Government","Architecture"],"significance_levels":["state","local"],"summary":{"what_it_is":"A district of about 54 acres at Lancaster Millpond on the Nashua River in Clinton, Massachusetts, built mainly between 1897 and 1915. It includes a dam, waste weir and spillway, two bridges, a gatehouse/powerhouse and a lightning arrester chamber.","why_significant":"It is the third phase of the metropolitan Boston water supply system and its most accessible and easily understood component. In August 1911 it produced the first known hydropower from a domestic water supply. It also shows unified landscape and architectural design, credited largely to Arthur Shurcliff of Olmsted & Olmsted.","narrative":"Wachusett Dam and its surrounding structures sit in the narrow gorge at the mouth of Wachusett Reservoir in Clinton, Massachusetts. The district includes an 850-foot gravity spillway with a 450-foot waste weir, two granite-faced concrete arch bridges, a symmetrical granite gatehouse and powerhouse, and a concrete lightning arrester chamber. Work on the dam began in 1900 and finished in 1906, as part of the third stage of Boston's metropolitan water supply. Engineers of the Metropolitan Water Board designed it under Frederic P. Stearns. Shepley, Rutan & Coolidge designed the powerhouse, and Arthur Shurcliff of Olmsted & Olmsted shaped the landscape. The rustic bridges and the rough-cut waste channel contrast with the formal powerhouse, circular pool and mulberry trees. In August 1911, power transmitted from the site became the first known hydroelectric generation from a domestic water supply. The district was listed for its association with the water system's development and for its design quality.","period_of_significance":"1897-1926","architect_builder":"Metropolitan Water Board engineering staff under Frederic P. Stearns, Chief Engineer; Shepley, Rutan & Coolidge (powerhouse); Arthur Shurcliff of Olmsted & Olmsted (landscape); McArthur Brothers of Chicago (contractor)","architectural_style":"Neoclassical (lower gatehouse/powerhouse); naturalistic Olmsted-influenced landscape with rustic granite-faced bridges","criteria":["A","C"],"status_note":"General condition is good; present use is water supply. The lightning arrester chamber roof, originally clay tile, is now asphalt shingle.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:12:59.942412-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/53/7932/63793253/content/electronic-records/rg-079/NPS_MA/89002269.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/89002269/667fca17d6-800.webp","url_1600":"https://nationalhistoricalregister.com/media/89002269/667fca17d6-1600.webp","licence":"CC BY-SA 3.0","author":"Martinde at en.wikipedia","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Wachusett-dam.jpg\" rel=\"noopener\">Martinde at en.wikipedia</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:Wachusett-dam.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/63793253","wikipedia":"https://en.wikipedia.org/wiki/Wachusett_Dam","wikidata":"https://www.wikidata.org/wiki/Q7958783"},"indexable":true,"url":"https://nationalhistoricalregister.com/massachusetts/worcester-county/wachusett-dam-historic-district-89002269/"}