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Photo, Print, Drawing Monongahela River Locks & Dam No. 2, At Monongahela River mile 11.2, Braddock, Allegheny County, PA

[ Drawings from Survey HAER PA-558  ]

More Resources

[ Data Pages from Survey HAER PA-558  ]
[ Photo Captions from Survey HAER PA-558  ]

About this Item

Title

  • Monongahela River Locks & Dam No. 2, At Monongahela River mile 11.2, Braddock, Allegheny County, PA

Names

  • Historic American Engineering Record, creator
  • U.S. Army Corps of Engineers, Pittsburgh District
  • Monongahela Navigation Company
  • Dravo Construction Company
  • N. D. Yant Company
  • J. & J. B. Milholland Company
  • Bair & Gazam Manufacturing
  • Moscarelli, Joseph
  • B. F. Jacobs Lumber Company
  • Penn Bridge Company
  • Roberts, T A
  • Mangold, Kyran
  • Skelley, Kerry
  • U.S. Army Corps of Engineers, Pittsburgh District, sponsor
  • Hampton, Roy, historian
  • Hardlines Design Company, contractor
  • Christianson, Justine, transmitter
  • Bates, Jeff, photographer
  • Judkis, Jim, photographer
  • Hardlines Design Company, delineator
  • McPartland, Mary, transmitter

Created / Published

  • Documentation compiled after 1968

Headings

  • -  locks (hydraulic facilities)
  • -  dams
  • -  miter gates
  • -  hydraulic power systems
  • -  butterfly valves
  • -  transportation
  • -  shipping
  • -  administration buildings
  • -  Pennsylvania--Allegheny County--Braddock

Latitude / Longitude

  • 40.391357,-79.85933180595799

Notes

  • -  Significance: Construction of Monongahela River Locks and Dam No. 2 was approved by Congress in 1902. The facility replaced a lock and dam structure built by the Monongahela Navigation Company in 1841 at river mile 11.8. The new dam had one lock in operation by 1905, and the entire structure was completed in 1906. It consisted of a concrete dam on wood pilings, surmounted by a movable crest Chittenden drum weir. The Chittenden weir was an innovative system that used water pressure to raise the movable crest. The Chittenden weir was replaced by a concrete fixed crest from 1921-22 due to operational problems. Further modernization of the dam and lock chambers took place shortly after World War II. New locks were completed in 1951 and 1953, respectively. The landward lock was the largest inland lock in the United States until 1959. A floodway bulkhead was used in the auxiliary chamber, which was innovative in concept and is unique in design to this day. This locks and dam complex is a reflection of engineering design of the period 1905-53, and is a contributing element to the historic Monongahela River Navigation System.
  • -  Survey number: HAER PA-558
  • -  Building/structure dates: 1904-1906 Initial Construction
  • -  Building/structure dates: 1921-1922 Subsequent Work
  • -  Building/structure dates: 1951 Subsequent Work
  • -  Building/structure dates: 1953 Subsequent Work
  • -  Building/structure dates: 2004 Demolished
  • -  Building/structure dates: 1917 Subsequent Work
  • -  Building/structure dates: 1931 Subsequent Work
  • -  Building/structure dates: 1987 Subsequent Work
  • -  Building/structure dates: 1996-1997 Subsequent Work
  • -  Building/structure dates: 1910-1911 Subsequent Work

Medium

  • Photo(s): 122
  • Measured Drawing(s): 6
  • Data Page(s): 14
  • Photo Caption Page(s): 17

Call Number/Physical Location

  • HAER PA-558

Source Collection

  • Historic American Engineering Record (Library of Congress)

Repository

Control Number

  • pa3774

Rights Advisory

Online Format

  • image
  • pdf

Rights & Access

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Obtaining Copies

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Cite This Item

Citations are generated automatically from bibliographic data as a convenience, and may not be complete or accurate.

Chicago citation style:

Historic American Engineering Record, Creator, Pittsburgh District U.S. Army Corps Of Engineers, Monongahela Navigation Company, Dravo Construction Company, N. D. Yant Company, J. & J. B. Milholland Company, Bair & Gazam Manufacturing, et al., Bates, Jeff, and Jim Judkis, photographer. Monongahela River Locks & Dam No. 2, At Monongahela River mile 11.2, Braddock, Allegheny County, PA. Allegheny County Pennsylvania Braddock, 1968. translateds by Christianson, Justinemitter, and Mcpartland, Marymitter Documentation Compiled After. Photograph. https://aj.sunback.homes/item/pa3774/.

APA citation style:

Historic American Engineering Record, C., U.S. Army Corps Of Engineers, P. D., Monongahela Navigation Company, Dravo Construction Company, N. D. Yant Company, J. & J. B. Milholland Company [...] Hardlines Design Company, D., Bates, J. & Judkis, J., photographer. (1968) Monongahela River Locks & Dam No. 2, At Monongahela River mile 11.2, Braddock, Allegheny County, PA. Allegheny County Pennsylvania Braddock, 1968. Christianson, J. & McPartland, M., transs Documentation Compiled After. [Photograph] Retrieved from the Library of Congress, https://aj.sunback.homes/item/pa3774/.

MLA citation style:

Historic American Engineering Record, Creator, et al., photographers by Bates, Jeff, and Jim Judkis. Monongahela River Locks & Dam No. 2, At Monongahela River mile 11.2, Braddock, Allegheny County, PA. trans by Christianson, Justinemitter, and Mcpartland, Marymitter Documentation Compiled After. Photograph. Retrieved from the Library of Congress, <aj.sunback.homes/item/pa3774/>.