{"nrhp_refnum":"04000164","name":"Dresden Island Lock and Dam Historic District","other_names":["Lock &amp","Dam 4"],"category":"district","location":{"address":"7521 N. Lock Rd.","address_restricted":false,"city":"Morris","county":"Grundy County","state":"IL","lat":41.40033404650006,"lon":-88.28184315499482,"geom_source":"nps_gis"},"listed_date":"2004-03-10","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Transportation","Maritime History","Engineering"],"significance_levels":["national"],"summary":{"what_it_is":"A lock and dam complex on the Illinois River near Morris, Grundy County, Illinois, built 1929-1933 by the State of Illinois and the US Army Corps of Engineers. It includes a lock, an incomplete auxiliary lock, a dam and a control station.","why_significant":"The district is significant under Criterion A for its role in the maritime, transportation and industrial history of the Illinois Waterway, which let commercial barges move between Chicago and the Mississippi River. It is significant under Criterion C as a good example of Army Corps of Engineers lock and dam construction of the period. It retains a high degree of integrity despite replaced equipment and surfaces.","narrative":"Dresden Island Lock and Dam is a navigation complex on the Illinois River near Morris, built between 1929 and 1933 and opened in 1933. The district contains a lock with a 22-foot lift and a 110 by 600 foot chamber, an unfinished auxiliary lock, a 1,505.5-foot concrete and earth dam, and a red brick control station with gabled bays reminiscent of the Jacobethan style. Walter Mickle Smith, Chief Design Engineer for the Illinois Waterway project, is considered the designer. The facility was part of a slackwater system that allowed commercial barges and towboats to travel the waterway between Chicago and the Mississippi River, and it helps maintain water levels at Lockport and Joliet. It was recognized for its role in transportation and maritime history and as a representative example of Army Corps of Engineers lock and dam design. Gates, machinery and surfaces have been replaced over the years, but the site keeps its original appearance and function. Three small modern buildings are noncontributing.","period_of_significance":"1929-1951","architect_builder":"Smith, Walter Mickle","architectural_style":"Other: lock and dam; No style: control station","criteria":["A","C"],"status_note":"Still an operating lock and dam facility; alterations are described as typical for continued operation.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:55:37.632678-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/52/8911/28891152/content/electronic-records/rg-079/NPS_IL/04000164.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/04000164/74b562e6dd-800.webp","url_1600":"https://nationalhistoricalregister.com/media/04000164/74b562e6dd-1600.webp","licence":"Public domain","author":"Grogan, Brian","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:CONTROL_STATION_AND_LOCK._LOOKING_EAST._-_Illinois_Waterway,_Dresden_Island_Lock_and_Dam_,_7521_North_Lock_Road,_Channahon,_Will_County,_IL_HAER_IL-164-F-1.tif\" rel=\"noopener\">Grogan, Brian</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:CONTROL_STATION_AND_LOCK._LOOKING_EAST._-_Illinois_Waterway,_Dresden_Island_Lock_and_Dam_,_7521_North_Lock_Road,_Channahon,_Will_County,_IL_HAER_IL-164-F-1.tif"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/28891152","wikipedia":"https://en.wikipedia.org/wiki/Dresden_Island_Lock_and_Dam","wikidata":"https://www.wikidata.org/wiki/Q5307013"},"indexable":true,"url":"https://nationalhistoricalregister.com/illinois/grundy-county/dresden-island-lock-and-dam-historic-district-04000164/"}