In just more than one month’s time, the U.S. Army Corps of Engineers Louisville Repair Station (LRS) has hoisted 500 tons of miter gate, welded steel and replaced and refurbished lock gate components after the Markland Lock gate failure Sept. 27.
Repairs are in full swing to open the Markland 1,200-foot lock chamber in April 2010. Both gate leaves have sustained some structural damages, but are repairable.
"A lot of progress has been made, and commerce continues to move on the river," said Gene Dowell, district locks and dam operations manager. "The team has been working really hard."
On Nov. 17, the Louisville repair fleet departed for its home base on Shippingport Island in Louisville, Ky., with the damaged downstream Markland lock miter gate leaves. There, repairs on the gate leaves and their components will continue. Repairs on the middle wall gate leaf started on site after the gate failed Sept. 27.
"The repairs we are doing now are intricate and time consuming work," said Tracey Keel, assistant operations manager for locks and dams.
The gates are slightly bent or warped and a significant amount of welding work needs to be done.
"A critical aspect of the work is to ensure the (repaired) leaves and the pintle ball area at the bottom and gudgeon pin at the top line up perfectly straight and true," said Keel. The repair crew will use lasers for precise alignment.
Before the mishap, new lock gates for Markland had been ordered, and now that delivery has been expedited by nine months so they will arrive by mid-March.
The Henry M. Shreve floating heavy-lift crane played a major role in setting in motion the second phase of repair work— the work that is done on Shippingport Island. The Shreve has a 550-ton lifting capacity and works up and down the Ohio River and beyond to lift gates out of lock chambers and onto other vessels for maintenance and repairs.
"Without the Shreve, we would have had to cut these gate leaves apart to get them out," said Greg Werncke, structural engineer. "This vessel has paid for itself many times over already."
The Shreve, custom-built in 2002, typically lifts gates vertically out of lock chambers, but the crew performed an unusual horizontal lift on the river wall gate leaf Nov. 10. Before the lift, eight lifting eyelets were welded onto the gate where it lay at the bottom of the lock chamber. The Shreve then hoisted the gate leaf up and out of the chamber pivoting 90 degrees to set the gate leaf onto a customized DeLong barge. (See the lift at You tube: http://www.youtube.com/watch?v=snVEimfekNA.)
"The DeLong barge has room to hold both damaged gates," said Dowell.
The DeLong barge is from St. Louis District.
Paling in size up against the monolithic Shreve, even the little work boat Motor Vessel Russelburg had a big job to do Nov. 10. The Russelburg helped to nudge the DeLong barge into perfect position to accept the 250-ton river wall gate leaf.
On Oct.19 the Shreve conducted the first vertical lift of the middle wall gate leaf. It was assessed for damages and structural integrity by Corps structural engineers and found to be repairable.