Appalachian History Series – Greenup Locks and Dam: The High-Lift Project That Remade the Middle Ohio River
At Lloyd, Kentucky, the Ohio River does not feel like a quiet boundary line. It feels like a working river. Barges move through a long pool of controlled water, traffic crosses high above the dam, and the river that once rose and fell around older wicket structures now passes through one of the great midcentury navigation projects of the Ohio Valley.
Greenup Locks and Dam stands on the Ohio River about five miles below Greenup, Kentucky, at a place where Greenup County, Kentucky and Scioto County, Ohio face each other across the water. The project belongs to the long history of the Ohio River as both a natural border and a commercial road. For eastern Kentucky and southern Ohio, it also tells a story about coal, steel, oil, electricity, river engineering, and the federal effort to keep inland navigation moving in an industrial age.
The dam was not built simply to hold back water. It was built to replace an older way of managing the Ohio River. Earlier locks and dams had helped create a dependable navigation channel, but by the middle of the twentieth century the needs of the river had changed. Towboats were larger. Barges were longer. Industry was heavier. The old system could not serve the river as well as it once had.
Greenup became part of the answer.
From Wicket Dams to Greenup
The Ohio River had been shaped for navigation long before Greenup was completed. In the early twentieth century, the federal government pushed toward a canalized river that could support year-round movement. The older wicket dams helped create a nine-foot channel, but their short locks and low lifts belonged to an earlier river age.
Those older structures worked, but they worked with limitations. Long modern tows often had to be broken apart. Lockage could take more time. Navigation depended on a chain of smaller dams rather than fewer high-lift projects. On a river that carried coal, petroleum, steel products, chemicals, grain, and other bulk goods, those delays mattered.
The new Greenup project was designed to replace Locks and Dams 27, 28, 29, and 30 on the Ohio River, along with Lock and Dam No. 1 on the Big Sandy River. That detail gives the project its scale. Greenup did not replace only one aging structure. It gathered several older pieces of the navigation system into one modern high-lift dam.
Its location also mattered. The dam was placed near the Kentucky and Ohio line, downstream from the Greenup and Ashland area and upstream from the Portsmouth region. This was a part of the Ohio Valley where river transportation, coal movement, power production, and heavy industry were closely connected. A better navigation pool here helped tie the Appalachian interior to the larger inland waterway system.
Building the Locks
Construction began in October 1954. The locks were started in October 1955 and were placed in operation on November 27, 1959. Dam construction began in June 1958, and the pool was raised to full height on June 4, 1962.
Those dates make the project look orderly on paper, but the work itself was difficult. Greenup was built in the river, not beside it. Engineers had to manage flowing water, cofferdams, construction staging, navigation traffic, and the constant risk of high water. Later Corps engineering manuals used Greenup as an example of cofferdam layout, noting that a three-stage arrangement was selected because high currents could otherwise affect navigation.
That kind of detail shows how Greenup was not just a concrete project. It was a river project. The builders had to keep the Ohio usable while also changing it.
High water made the work harder. One major high-water event in January 1959 damaged a cofferdam, and another in February 1961 overtopped cofferdams and damaged equipment. These problems did not stop the project, but they show the central challenge of building a major dam on the Ohio River. The river did not pause for construction.
The Corps also studied the project through hydraulic modeling. Waterways Experiment Station reports examined navigation conditions around Greenup and the spillway design before and during the project era. Those studies were part of the hidden engineering behind the final structure. The finished dam may look fixed and permanent, but it came from years of planning, testing, and adjustment.
The Shape of the Finished Project
Greenup Locks and Dam was built as a high-lift, movable gated dam. The project includes two parallel locks. The main lock is 110 feet wide and 1,200 feet long, large enough to handle long modern tows more efficiently than the older 600-foot lock chambers it replaced. The auxiliary lock is 110 feet wide and 600 feet long.
The dam itself has nine tainter gates. Each gate could be raised or lowered to help control the river. The Corps lists the dam as 1,287 feet long at the top, including a fixed weir section and an open crest. The normal upper pool elevation is 515 feet above mean sea level, with a normal lift of about 30 feet.
The pool behind Greenup stretches 61.8 miles upstream to what is now Robert C. Byrd Locks and Dam. That long pool is one of the central changes Greenup brought to the river. Instead of several smaller pools controlled by older wicket dams, the project created a deeper and more dependable stretch of navigable water.
For towboat crews, this mattered in practical terms. Fewer older locks meant fewer slow passages. Larger chambers meant fewer broken tows. A steadier pool meant more reliable movement. Greenup helped make the Ohio River work more like the modern freight corridor that industry expected it to be.
Dedication on the Ohio
By the summer of 1962, Greenup had become more than a construction site. It was a public event. The dedication of the new locks and dam took place around July 22, 1962, with river people, government officials, industry leaders, and local spectators gathered around the project.
A later Waterways Journal account, drawing from its July 28, 1962 coverage, described a towboat parade traveling from Ashland downstream to the new dam. The parade included well-known Ohio River boats and reflected the pride of the river industry. The ceremony was not only about concrete, gates, and locks. It marked a change in how the middle Ohio would move goods and support industry.
There is a small dating issue in the source trail. A postcard record from the Scioto County Public Library dates the dedication to July 21, 1962, while federal cataloging for Secretary of Commerce Luther H. Hodges’s dedication address and the Waterways Journal account point to July 22. Unless an original dedication program is found showing otherwise, July 22 is the stronger date to use for the ceremony.
The dedication also shows how much Greenup belonged to the wider Ohio Valley. It served Kentucky and Ohio, but it also mattered to West Virginia, Pennsylvania, and the inland river system as a whole. A dam at Greenup affected freight patterns far beyond Greenup County.
Hydropower at the Dam
Greenup later gained another role through hydropower. The Corps dam itself was a navigation project, but the Ohio abutment became the site of a hydroelectric plant operated by the City of Hamilton, Ohio. The plant uses three turbines and is generally described as a 70 to 70.2 megawatt run-of-river hydroelectric facility.
The hydro plant became operational in 1982. Its story connects Greenup to another part of the Ohio River’s modern history: the use of existing navigation dams for power generation. Instead of building a separate power dam, the hydroelectric project used the federal navigation structure already in place.
The City of Hamilton and American Municipal Power later became tied together in the ownership and licensing story. Hamilton retained a majority interest, while AMP acquired a 48.6 percent ownership interest. Today, the plant supplies power to participating municipal communities in several states.
This makes Greenup more than a lock and dam. It is a navigation structure, a transportation asset, a power site, and a long-term federal and municipal infrastructure project.
The Bridge Above the River
The Jesse Stuart Memorial Bridge added another layer to Greenup’s story. Built across the dam site in the 1980s, the bridge connects Kentucky and Ohio above the locks and dam. Its name honors Jesse Stuart, the Greenup County writer whose work helped carry eastern Kentucky life into American literature.
That connection is fitting. Greenup Locks and Dam is an industrial structure, but it also belongs to local memory. For many families in Greenup County, Scioto County, and the surrounding river communities, the dam is not just an engineering project. It is a landmark. It is a place seen from the highway, crossed by bridge, visited for fishing, watched by children, and remembered by people who grew up along the Ohio.
Infrastructure often becomes part of a region’s everyday geography. Greenup did that. It changed the river, but it also became part of how people understood the river.
Greenup Today
Greenup Locks and Dam remains part of the U.S. Army Corps of Engineers navigation system. It sits within a network of Ohio River locks and dams that operate around the clock to keep inland commerce moving. Federal water data, river forecasts, navigation charts, and Corps project pages continue to document its operation.
The project also continues to age. The Corps replaced aging gates at Greenup in 2012, and modern rehabilitation planning has continued through formal review processes. That is the nature of large public works. They are never truly finished. They are built, used, repaired, studied, modernized, and passed forward.
The river has changed since 1962. So has the economy around it. Some industries have declined, some freight patterns have shifted, and the Ohio Valley has faced new challenges. Yet Greenup Locks and Dam still tells the same basic story. The Ohio River remains a working river, and Greenup remains one of the structures that makes that work possible.
Why Greenup Matters
Greenup Locks and Dam matters because it represents a turning point in the middle Ohio River. It replaced an older chain of wicket dams with a modern high-lift project. It shortened and simplified navigation through a busy stretch of river. It created a long pool, supported industrial transportation, and later became a site of hydroelectric generation.
For Appalachian Kentucky, the project also shows how local places are tied to large systems. Greenup County may seem like one county along one river, but the dam connects it to coalfields, power plants, municipal utilities, federal engineering offices, towboat companies, and national commerce. The structure at Lloyd is local history and national infrastructure at the same time.
Standing at Greenup, the Ohio River looks controlled, but it is not conquered. The old floods, cofferdam failures, hydraulic studies, and continuing maintenance all remind us that the river still has to be respected. Greenup Locks and Dam is a monument to that balance. It is a place where engineers reshaped the river without ever escaping the river’s power.
Sources & Further Reading
United States Army Corps of Engineers, Great Lakes and Ohio River Division. “Greenup Locks and Dam.” January 10, 2024. Accessed June 2, 2026. https://www.lrd.usace.army.mil/Missions/Projects/Display/Article/3640169/greenup-locks-and-dam/
United States Army Corps of Engineers. “Greenup Locks and Dam.” Water Data. Accessed June 2, 2026. https://water.usace.army.mil/overview/lrh/locations/greenupld
United States Army Corps of Engineers, Great Lakes and Ohio River Division. “Navigation on the Ohio River.” Accessed June 2, 2026. https://www.lrd.usace.army.mil/Water-Information/Navigation/Ohio-River/
United States Army Corps of Engineers. Ohio River Navigation Charts: Foster, Kentucky, to New Martinsville, West Virginia. Revised January 2014. Accessed June 2, 2026. https://www.lrl.usace.army.mil/Portals/64/docs/Ops/Navigation/Charts/Ohio_River/Charts_2014/Charts_1-122.pdf
United States Geological Survey. “Ohio River at Greenup Dam Near Greenup, KY, Monitoring Location 03216600.” Accessed June 2, 2026. https://waterdata.usgs.gov/monitoring-location/03216600/
National Oceanic and Atmospheric Administration, National Water Prediction Service. “Ohio River at Lloyd Greenup Lock, GNUK2.” Accessed June 2, 2026. https://water.noaa.gov/gauges/gnuk2
United States Army Corps of Engineers. Annual Report of the Chief of Engineers, U.S. Army, on Civil Works Activities, 1954. Washington, DC: Government Printing Office, 1954. Accessed June 2, 2026. https://usace.contentdm.oclc.org/digital/collection/p16021coll6/id/957/
United States Army Corps of Engineers. Annual Report of the Chief of Engineers, U.S. Army, on Civil Works Activities, 1956. Washington, DC: Government Printing Office, 1956. Accessed June 2, 2026. https://usace.contentdm.oclc.org/digital/collection/p16021coll6/id/150/
United States Army Corps of Engineers. Annual Report of the Chief of Engineers, U.S. Army, on Civil Works Activities, 1962. Washington, DC: Government Printing Office, 1962. Accessed June 2, 2026. https://usace.contentdm.oclc.org/digital/collection/p16021coll6/id/257/
United States Army Corps of Engineers. Annual Report of the Chief of Engineers, U.S. Army, on Civil Works Activities, 1963. Washington, DC: Government Printing Office, 1963. Accessed June 2, 2026. https://usace.contentdm.oclc.org/digital/collection/p16021coll6/id/269/
United States Army Engineer Waterways Experiment Station. Navigation Conditions at Greenup Locks and Dam, Ohio River: Hydraulic Model Investigation. Vicksburg, MS: Waterways Experiment Station, 1958. Accessed June 2, 2026. https://catalog.hathitrust.org/Record/100393844
United States Army Engineer Waterways Experiment Station. Navigation Conditions at Greenup Locks and Dam, Ohio River: Hydraulic Model Investigation. Vicksburg, MS: Waterways Experiment Station, 1958. Accessed June 2, 2026. https://upload.wikimedia.org/wikipedia/commons/8/83/Navigation_conditions_at_Greenup_Locks_and_Dam%2C_Ohio_River-_Hydraulic_model_investigation_-_USACE-p266001coll1-1763.pdf
United States Army Corps of Engineers. Engineering and Design: Hydraulic Design of Navigation Locks. EM 1110-2-1604. Washington, DC: Department of the Army, May 1, 2006. Accessed June 2, 2026. https://www.publications.usace.army.mil/Portals/76/Publications/EngineerManuals/EM_1110-2-1604.pdf
United States Army Corps of Engineers. Engineering and Design: Hydraulic Design of Navigation Dams. EM 1110-2-1605. Washington, DC: Department of the Army, May 12, 1987. Accessed June 2, 2026. https://www.publications.usace.army.mil/Portals/76/Publications/EngineerManuals/EM_1110-2-1605.pdf
United States Army Corps of Engineers. Greenup Locks and Dam, Major Rehabilitation Evaluation Report: Review Plan, Implementation Document. February 2, 2024. Accessed June 2, 2026. https://www.lrd.usace.army.mil/News/Project-Documents-Notices-Public-Review/Category/24694/kentucky/
Inland Marine Transportation Systems Capital Investment Strategy Team. Inland Marine Transportation Systems Capital Projects Business Model Final Report. April 13, 2010. Accessed June 2, 2026. https://www.iwr.usace.army.mil/Portals/70/docs/IWUB/IMTS_Final_Report_13_April_2010_Rev_1.pdf
Inland Waterways Users Board. 15th Annual Report. August 2001. Accessed June 2, 2026. https://www.iwr.usace.army.mil/Portals/70/docs/IWUB/annual/IWUB_Annual_Report_2001.pdf
United States Army Engineer Research and Development Center. Emergency Closure of Uncontrolled Flow at Locks and Dams. ERDC/CHL TR-12-8. Vicksburg, MS: Engineer Research and Development Center, June 2012. Accessed June 2, 2026. https://usace.contentdm.oclc.org/digital/api/collection/p266001coll1/id/4565/download
United States House of Representatives. How Reliability of the Inland Waterway System Impacts Economic Competitiveness. Hearing before the Subcommittee on Water Resources and Environment. Washington, DC: Government Printing Office. Accessed June 2, 2026. https://www.govinfo.gov/
Federal Energy Regulatory Commission. “City of Hamilton, Ohio and American Municipal Power, Inc.; Notice of Application Tendered for Filing with the Commission and Soliciting Additional Study Requests.” Federal Register 89, no. 47, March 8, 2024. Accessed June 2, 2026. https://www.federalregister.gov/documents/2024/03/08/2024-04915/city-of-hamilton-ohio-and-american-municipal-power-inc-notice-of-application-tendered-for-filing
Federal Energy Regulatory Commission. “City of Hamilton, Ohio, American Municipal Power, Inc.; Notice of Application Accepted for Filing, Soliciting Motions to Intervene and Protests, Ready for Environmental Analysis, and Soliciting Comments, Recommendations, Terms and Conditions, and Prescriptions.” Federal Register 90, no. 17, January 28, 2025. Accessed June 2, 2026. https://www.govinfo.gov/content/pkg/FR-2025-01-28/html/2025-01768.htm
Federal Energy Regulatory Commission. “City of Hamilton, Ohio, American Municipal Power, Inc.; Notice Soliciting Scoping Comments.” Federal Register, June 25, 2025. Accessed June 2, 2026. https://www.federalregister.gov/documents/2025/06/25/2025-11678/city-of-hamilton-ohio-american-municipal-power-inc-notice-soliciting-scoping-comments
Federal Energy Regulatory Commission. “City of Hamilton, Ohio and American Municipal Power, Inc.; Notice of Intent to Prepare an Environmental Assessment.” Federal Register, February 23, 2026. Accessed June 2, 2026. https://www.federalregister.gov/documents/2026/02/23/2026-03574/city-of-hamilton-ohio-and-american-municipal-power-inc-notice-of-intent-to-prepare-an-environmental
Federal Energy Regulatory Commission. “City of Hamilton, Ohio and American Municipal Power, Inc.; Notice of Authorization for Continued Project Operation.” Federal Register, March 19, 2026. Accessed June 2, 2026. https://www.govinfo.gov/content/pkg/FR-2026-03-19/html/2026-05427.htm
Federal Energy Regulatory Commission. “Letter Accepting License Application for Filing, Greenup Hydroelectric Project, P-2614-042.” Accession no. 20250121-3074. January 21, 2025. Accessed June 2, 2026. https://elibrary.ferc.gov/eLibrary/filelist?accession_Number=20250121-3074
City of Hamilton, Ohio. “Greenup Hydroelectric Plant.” Accessed June 2, 2026. https://www.hamilton-oh.gov/greenup-licensing
American Municipal Power. “Greenup Hydroelectric Project.” Accessed June 2, 2026. https://www.amppartners.org/generation/hydroelectric-power/greenup-hydroelectric-plant/
American Municipal Power. Greenup Hydroelectric Project Revenue Bonds, Series 2016A, Official Statement. 2016. Accessed June 2, 2026. https://emma.msrb.org/
West, Eugene M. Head Determinations for Structures on U.S. 23 that are Affected by Raising the Normal Pool Elevation of Ohio River Lock and Dam No. 30 at Greenup, Kentucky. Kentucky Highway Materials Research Laboratory Report No. 81. Lexington: University of Kentucky, July 1952. Accessed June 2, 2026. https://uknowledge.uky.edu/ktc_researchreports/1296/
United States Government Printing Office. Monthly Catalog of United States Government Publications. Entry for Luther H. Hodges, Greenup Locks and Dam dedication address, July 22, 1962. Accessed June 2, 2026. https://www.govinfo.gov/content/pkg/GOVPUB-GP3-c937557e21a738abe47fe7c5a8c6b158/pdf/GOVPUB-GP3-c937557e21a738abe47fe7c5a8c6b158.pdf
Scioto County Public Library Local History Digital Collection. “Greenup High Level Dam & Lock.” 1962 postcard. Accessed June 2, 2026. https://www.sciotolibrary.org/history/items/show/21671
Smith, David. “Parade Highlights Greenup Opening 63 Years Ago.” The Waterways Journal, July 25, 2025. Accessed June 2, 2026. https://www.waterwaysjournal.net/2025/07/25/parade-highlights-greenup-opening-63-years-ago/
Cahal, Sherman. “Greenup Locks and Dam.” Bridges & Tunnels, September 7, 2023. Accessed June 2, 2026. https://bridgestunnels.com/location/greenup-locks-and-dam/
Cahal, Sherman. “From Wicket Dams to a ‘Super Dam’: A History of the Greenup Locks and Dam.” Bridges & Tunnels, September 8, 2023. Accessed June 2, 2026. https://bridgestunnels.com/2023/09/08/from-wicket-dams-to-a-super-dam-a-history-of-the-greenup-locks-and-dam/
Cahal, Sherman. “Jesse Stuart Memorial Bridge.” Bridges & Tunnels, March 2, 2020. Accessed June 2, 2026. https://bridgestunnels.com/location/jesse-stuart-memorial-bridge/
Kentucky Transportation Cabinet, District 9. “Work at Greenup Locks and Dam Will Affect KY 10 Jesse Stuart Memorial Bridge Traffic.” January 13, 2017. Accessed June 2, 2026. https://transportation.ky.gov/DistrictNine/Pages/PressReleasePage.aspx?FilterField1=ID&FilterValue1=256
Ohio River Valley Water Sanitation Commission. Biennial Assessment of Ohio River Water Quality Conditions. 2008. Accessed June 2, 2026. https://www.orsanco.org/
Ohio River Valley Water Sanitation Commission. “Locks and Dams, Tributaries, Flow, and Ohio River Discharges.” In 2012 Ohio River 305(b) Report Appendices. Accessed June 2, 2026. https://www.orsanco.org/wp-content/uploads/2016/07/2012ohioriver305breportappendices.pdf
Marshall University Special Collections. “G. W. ‘Jerry’ Sutphin River Transportation Collection.” Accessed June 2, 2026. https://www.marshall.edu/special-collections/
Marshall University Special Collections. “Herald-Dispatch Archives.” Accessed June 2, 2026. https://www.marshall.edu/special-collections/
Loesch v. United States. Federal legal source on Ohio River navigation works and federal river authority. Accessed June 2, 2026. https://law.justia.com/
Author Note: I have always found river infrastructure interesting because it shows how local places are tied to national systems. Greenup Locks and Dam is a good example of that, since one structure in Greenup County changed navigation, power, and transportation across a much wider stretch of the Ohio River.