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Emsworth Locks & Dams Major Rehabilitation Project

Pittsburgh District
Published Jan. 9, 2024
Pittsburgh District geotechnical engineers and geologists study subsurface terrain to assess bedrock for construction projects. A marine drilling crew has been working at Emsworth Locks and Dams since July to drill more than 50 boreholes. The geotechnical team will send samples to a lab to identify the bedrock hardness, strength and permeability for construction. The district plans on constructing a newer, larger lock chamber at Emsworth as part of the Upper Ohio Navigation Project.

A marine drilling crew contracted by the U.S. Army Corps of Engineers Pittsburgh District collects samples of bedrock on the Ohio River near the Emsworth Locks and Dams in Pittsburgh, Sept. 27, 2023. Pittsburgh District geotechnical engineers and geologists study subsurface terrain to assess bedrock for construction projects. A marine drilling crew has been working at Emsworth Locks and Dams since July to drill more than 50 boreholes. The geotechnical team will send samples to a lab to identify the bedrock hardness, strength and permeability for construction. The district plans on constructing a newer, larger lock chamber at Emsworth as part of the Upper Ohio Navigation Project. (U.S. Army Corps of Engineers Pittsburgh District photo by Michel Sauret)

Project Location and Description

Emsworth Locks and Dams are located on the Ohio River immediately downstream of the City of Pittsburgh.  The main channel dam and locks are located at river mile 6.2 and the back channel dam is located at river mile 6.8.  The project creates the navigation pool for the City of Pittsburgh.  The structural components of the Emsworth Locks and Dams are the oldest of any project on the Ohio River, dating back to 1919 to 1922 and 1935 to 1938 when Emsworth Dams were constructed.  The Emsworth locks, consisting of a 110’ wide by 600’ long main chamber and 56’ wide by 360’ long auxiliary chamber, are the oldest on the Ohio River System and are in need of additional maintenance work to keep them operating safely until permanent improvements are implemented.

Current Status

The Emsworth Dams are presently in an exigent situation.  Four significant project features – the scour protection, vertical lift gates, gate operating machinery and emergency bulkheads – were identified to have a high risk of failure.  Prior to temporary, emergency repairs to the scour protection downstream of the dams, there were 10’ deep scour holes and 65 percent of the scour protection was in a failed state.  A temporary repair was completed in February 2005 by in-filling the scour holes with stone.  Due to the temporary nature of the repair, soundings are required on an annual basis and following major flood events until a permanent repair is in place.  Due to the extremely corroded state of the dam gates, failure of any one of the thirteen lift gates would most likely cause undermining of a portion of the stilling basin causing it to fail and possibly undermine the dam causing the dam piers to be displaced.  There is presently a 76 percent likelihood of failure of one of the dam gates.  The gate operating systems are proven to be unreliable, due to multiple failures within the past several years.  The emergency bulkheads were determined to be unsafe to work behind and therefore replaced in 2006.

The best plan for the locks will be evaluated as part of the Upper Ohio Navigation Study.  A Major Rehabilitation Evaluation Report for the dams recommending the project was approved in 2002.  The project includes providing permanent scour protection and replacement of the vertical lift gates, gate operating machinery and emergency bulkheads.  $3.5M was provided in 2004 and 2005 through the Dam Safety Seepage and Stability program and an additional $32M has been provided through FY 2007.  The FY 2008 President’s budget request includes $43M for this project.  Features of work that have been completed and/or initiated include temporary scour protection downstream of both dams, fabrication of emergency bulkheads and dam gates, replacement of back channel dam gates, bulkhead hoist replacement, and design of the permanent scour protection and abutments stabilization.  Work scheduled for future years includes replacement of main channel dam gates, dam scour protection and dam service bridges.  With efficient funding, the project will be completed in 2014.

 Issues and Other Information

Until the dam gates and machinery are replaced and permanent scour protection is provided the loss of the Emsworth Pool may occur.  The total benefits of traffic through Emsworth reflect a savings of $300 million each ear over other modes of transportation.  If the Emsworth pool is lost, two major facilities dependent on river transportation are impacted – the US Steel Clairton Works, the largest coke plant in the United States and the Bailey/Enslow Fork Complex owned by Consol Energy, the largest underground coal mine in the United States. Disruption in coal supply and transportation would also impact steel plants and coal-fired electric power plants.  The impact of the loss of Emsworth pool on the local economy and other communities would be substantial.  Approximately 11,700 jobs would be directly at risk due to loss of navigation and disruption to services and material. The loss in wages alone would range from $1.5 to $2.2 million per day.

Authorization

Rivers and Harbors Act of July 1918 (Public Law 65-37; 40 Stat 250, 257, Ch. 49

Appropriation

Construction, General