{"nrhp_refnum":"00000401","name":"Allegheny River Lock and Dam No. 7","other_names":[],"category":"structure","location":{"address":"Along PA 4023, 0.6 mi. N of Kittanning Br.","address_restricted":false,"city":"Kittanning","county":"Armstrong County","state":"PA","lat":40.82047606750007,"lon":-79.52880243457446,"geom_source":"nps_gis"},"listed_date":"2000-04-21","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Transportation","Maritime History","Architecture","Engineering"],"significance_levels":["state"],"summary":{"what_it_is":"A lock and dam on the Allegheny River at Kittanning, Armstrong County, Pennsylvania, on the west bank, consisting of a lock, dam, esplanade and operations building. It was constructed by the U.S. Army Corps of Engineers in 1928-1930, 45.7 miles upstream from the river's mouth.","why_significant":"The nomination argues the lock and dam is significant for its role in the Allegheny River navigation system, providing slackwater access to commercial barge and towboat traffic and to resources north of Kittanning. It is also presented as a representative example of lock and dam construction of 1928-1930, retaining its original appearance, machinery and function.","narrative":"Lock and Dam No. 7 is a navigation structure on the west bank of the Allegheny River at Kittanning, Pennsylvania, 45.7 miles above the river's mouth. The U.S. Army Corps of Engineers built it between 1928 and 1930, with Dravo Corporation as contractor, using standard designs adapted to the site. The complex includes a 56-by-360-foot lock with a 13-foot lift, a 916-foot fixed-crest dam, a concrete esplanade, and a two-story operations building that houses hydraulic pumps driven by water turbines. The dam's gravel-filled cylindrical sheet piling caused debate among Corps officials before stone was added downstream. The facility opened on November 10, 1930, and gave barges access to about 72 miles of the Allegheny. It is valued for its part in the river's transportation network and for preserving much of its original machinery and layout.","period_of_significance":"1903-1948","architect_builder":"Dravo Corporation (contractor)","architectural_style":"Late Nineteenth and Early Twentieth Century Revival","criteria":["A","C"],"status_note":"In operation; alterations include gate and valve replacements, a gas heating system and a 1992-1994 renovation.","vacant_flag":false,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:36.181458-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/00000401.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/00000401/4fec4ffd0c-800.webp","url_1600":"https://nationalhistoricalregister.com/media/00000401/4fec4ffd0c-1600.webp","licence":"Public domain","author":"User:Nyttend","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Waterside.jpg\" rel=\"noopener\">User:Nyttend</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Waterside.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71992268","wikipedia":"https://en.wikipedia.org/wiki/Allegheny_River_Lock_and_Dam_No._7","wikidata":"https://www.wikidata.org/wiki/Q4731340"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/armstrong-county/allegheny-river-lock-and-dam-no-7-00000401/"}