{{Use American English|date=July 2025}} {{Use mdy dates|date=March 2025}} {{Infobox NRHP | name = Redridge Steel and Log Dams | nrhp_type = | image = Redridge Steel Dam from Downstream.jpg | caption = Redridge Steel Dam (downstream side) | coordinates = {{coord|47|8|56|N|88|45|50|W|display=inline,title}} | location = Stanton Township, Houghton County, Michigan, USA | locmapin = Michigan#USA | mapframe = yes | mapframe-marker = dam | mapframe-zoom = 12 | mapframe-caption = Interactive map | area = | built = 1894 | architect = | architecture = | added = April 2, 1992 | refnum = 92000166 <ref name="nris">{{NRISref|2007a}}</ref> }}
The '''Redridge Steel Dam''' is a steel dam across the Salmon Trout River in Redridge, Houghton County, Michigan. Completed in 1901, it is a flat slab buttress dam constructed of steel, a relatively rare material for construction of dams, which are typically made of earthenworks, concrete, or masonry. Most sources indicate that it was one of only three such dams constructed in the United States, the other two being the Ashfork-Bainbridge Steel Dam (1898, Arizona) and the Hauser Lake Dam (1907, Montana), the last of which failed within a year of construction.
==History== In 1894, prior to the construction of the steel dam, the Atlantic Mining Company built a timber crib dam across the Salmon Trout River. The dam created a reservoir which supplied water to the Atlantic stamp mill which extracted copper from ore-bearing rock. With the growth of the Atlantic stamp mill and the construction of the Baltic Mining Company mill nearby, this reservoir proved to be insufficient, and in 1901 the steel dam was built. It was designed by J. F. Jackson and built by the Wisconsin Bridge and Iron Company. The old timber crib dam remained in place, submerged, upstream of the steel dam. A system of spillways, sluices (or ''launders'' as they are referred to in contemporary texts), and pipes brought water downhill to the stamp mills. The dam itself measures 74 ft (23 m) high at its center and extends for a length of 1,006 ft (307 m) across the river. Access to the reservoir was shared by the Atlantic and Baltic mines, which had a common board of directors.
The dam operated for several decades, until the mines closed. After that time, the dam was no longer maintained. On Easter morning of 1941, the spillway behind the dam broke, causing a flood. There was little damage to the steel part of the dam, but with the mining operations stopped, the dam owners had the spillway valves opened. However, there were still incidents of overtopping,<ref>As illustrated in this: [https://web.archive.org/web/20220613000035/http://www.geocities.com/Athens/Aegean/2272/overtop1.jpg overtopping image]</ref> and the Copper Range Company (successor to Atlantic Mine Company and owner of the dam) had large holes cut in it in 1979 so that it would not retain water. This lowered the level of the reservoir, revealing the earlier timber dam.<ref>The dam in this illustration of the Dam article is actually the earlier timber crib dam replaced by the Redridge Steel Dam</ref>
Ownership of the dam was transferred to Stanton Township in 1992. Fears that the timber dam might fail and Michigan's Department of Environmental Quality considering the dam a "significant hazard" forced the township to consider renovating the dam in 2001. Five options were proposed for a long-term fix for the dam. These options ranged from repairing the steel and wooden dams for $311,000 to restoring/reconstructing the entire structure for over a million dollars. Stanton Township could not afford to do any of the proposed options, so another option was sought out. A short-term fix was found to make the dam safer. The upper 13 feet of the wooden structure was removed in 2004 to bring the water level down and relieve some of the pressure. A more permanent repair is still needed. A recent study{{when|date=June 2018}} by a team of students from Michigan Technological University determined that both dams are likely to remain safe for the foreseeable future.{{citation needed|date=June 2018}}
==Gallery== <gallery mode = packed> File:RedridgeSteelDam01.jpg|Redridge Steel Dam (upstream side, showing holes cut) File:Underside of the Redridge Steel Dam.jpg|The underside of the western end of the steel dam, downstream side File:RedridgeSteelDam02.jpg|(upstream side) from HAER </gallery>
== Construction information == Steel dams use relatively thin steel plates in contact with the water body, with a framework of steel behind them transmitting the load to the ground. The plates are slanted upwards in the direction of water flow, so that the weight of the water puts compressive forces on the girders holding the plates up. This transmits force to the ground without the bending moment that a vertical wall of plates would engender. It was believed at the time that these dams could be constructed faster and more cheaply than masonry dams.<ref>{{cite journal |last=Reynolds |first=Terry S. |date=1989 |title=A Narrow Window of Opportunity: the Rise and Fall of the Fixed Steel Dam |journal=IA, The Journal of the Society for Industrial Archeology |volume=15 |issue=1 |pages=1–20 |jstor=40968160 }}</ref>
==Geography and site information== Redridge is in Houghton County, one of the more rugged counties in Michigan, and access to the dam site is relatively challenging, although there is a history of Michigan Technological University students making pilgrimages to the site, especially those interested in industrial archaeology.
==Historic designations== *National Register of Historic Places, listed April 2, 1992 *Michigan Historic Civil Engineering Landmark, designated in 1985<ref>This image [http://www.hu.mtu.edu/~dcclark/images/orientation2005/DSC00992.jpg (The Redridge ASCE Plaque)] of a plaque on the site shows the date of designation</ref>
== See also == * Hauser Dam: a steel dam in Montana
==Notes== {{Reflist}}
==External links== {{Commons category}} *[https://web.archive.org/web/20220623090333/http://www.geocities.com/Athens/Aegean/2272/redsite1.jpg Redridge] site map, the steel dam is marked "new dam" *{{Structurae |id=20001384 |title=Redridge Steel Dam}} *Historic American Engineering Record (HAER) documentation: **{{HAER |survey=MI-10 |id=mi0143 |title=Redridge Steel Dam, Salmon Trout River, Beacon Hill, Houghton County, MI |link=no}} **{{HAER |survey=MI-11 |id=mi0144 |title=Redridge Timber Crib Dam, Salmon Trout River, Beacon Hill, Houghton County, MI |link=no}} *[http://www.uq.edu.au/~e2hchans/steel_da.html A Brief History of Steel Dams by Hubert Chanson] *[http://www.copperrange.org/redridge.htm Redridge page] at Copper Range Historical Society site *[https://web.archive.org/web/20000310202154/http://www.geocities.com/Athens/Aegean/2272/redweb01.htm Industrial Heritage of Redridge Michigan] by Robert Goniea *[http://coppercountryexplorer.com/category/redridge-dam/ Dam Ruins] - an exploration of the Redridge Dams as they appear today
==Further reading== *{{Cite book |last=Jackson |first=Donald C. |date=1984 |title=Great American Bridges and Dams |location=New York |publisher=John Wiley & Sons |pages=[https://archive.org/details/greatamericanbri0000jack/page/210 210–211] |isbn=0-471-14385-5 |url=https://archive.org/details/greatamericanbri0000jack/page/210 }} *{{Cite book |last=Punmia |first=B. P. |date=1992 |title=Irrigation and Water Power Engineering |url={{Google books|yVwrv9tF8AUC|Irrigation and Water Power Engineering|page=300|plainurl=yes}} |publisher=Firewall Media |page=300}} One of few sources to mention steel dams, this book says there are 3 extant in the U.S. and gives some info. *[https://web.archive.org/web/20070929180816/http://www.wuppdr.org/pdfs/CCT/pdf%2003%20apend.pdf Copper Country Trail] appendix listing historic Copper Country places
<!-- (caption from above via OCR)
HAER No. MI—10 HISTORIC AMERICAN ENGINEERING RECORD INDEX TO PHOTOGRAPHS Redridge Steel Dam Across the Salmon Trout River Beacon Hill Houghton County Michigan NOTE: Photograph was taken by Jet Lowe, HAER photographer, in July 1978. MI-l0D—i VIEW LOOKING AT UPSTREAM SIDE OF DAM.
Redridge Steel and Log Dams – The Redridge dams are situated adjacent to the village of Redridge and straddle the Salmon Trout River about one-half mile from its confluence with Lake Superior. This steel dam was constructed between 1900 and 1901. Although the reservoir has been drained for safety reasons, its concrete and steel components survive intact, except for the removal of several sections of plating at the dam's base to ensure sufficient flow during periods of high water. A few hundred feet upstream stands a second structure, a stone-filled, log crib dam built in 1894. The Redridge steel dam is one of three fixed steel dams constructed in the United States between 1895 and 1910. It is the larger of only two surviving examples of its type. The dam exemplifies a type of construction briefly considered as an alternative to more traditional methods of dam construction. Plans for the steel dam were provided by John F. Jackson, regional engineer for the Wisconsin Bridge and Iron Company of Milwaukee. The dam was constructed to provide water for the Baltic Mining Company and Atlantic Mining Company, both of which operated stamp mills in the area. The nearby log crib dam is an extremely rare survivor of many such structures built in Michigan in the nineteenth century. It was constructed by the Atlantic Mining Company to provide water for its stamp mill. Designation: National Register, listed April 2, 1992
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{{National Register of Historic Places listings in Houghton County, Michigan}} {{Registered Historic Places}}
Category:Dams on the National Register of Historic Places in Michigan Category:Dams completed in 1901 Category:United States local public utility dams Category:Historic American Engineering Record in Michigan Category:Steel dams Category:National Register of Historic Places in Houghton County, Michigan Category:1901 establishments in Michigan