Two New Lift Gates Installed At Mel Price
In the final stretch of a complex project whose origins go back to 2018, two new lift gates have been installed in the main lock chamber at Mel Price Lock and Dam in St. Louis. They are replacing three older lift gates, which were damaged during a barge strike in 2018, necessitating emergency repairs and a replacement process. The temporary repairs allowed the gates to continue operating, but engineers found a permanent global twist that required replacement.
The first gate was lifted into place March 19. The target date for full installation and completion of all testing of the new gates is April 4.
The new gate leaves were fabricated by G&G Steel in Russellville, Ala., and barged to the project site in Corps of Engineers barges. They are 110 feet across and weigh about 520,000 pounds each. The Corps barge crane that lifted them into place was borrowed from the Rock Island District.
Andy Schimpf, St. Louis Engineer District rivers project manager, explained that lift gates are more complex and expensive than the miter gates used at locks and dams farther downriver. Lift gates are also used at Lock and Dam 27. They are necessary for locks that handle large amounts of ice because they can be partly lowered to allow ice to be flushed from the lock chamber, reducing wear and tear on the pintles or hinges of the lock gates in what is already the second-busiest lock in the system. Miter gates are less expensive but would have to open and shut to “lock through” the ice as if it were a tow. “A large tow could push a thousand feet of ice ahead of it,” Schimpf explained.
The old gates, which will be scrapped, are being temporarily stored on the Missouri bank of the Mississippi River next to the lock and dam. They were fabricated two years before the official opening of Mel Price in 1989. Although the 2018 barge strike accelerated their replacement timeline, Schimpf said they would have had to be replaced soon anyway. “As they say, it’s not the years, it’s the mileage. So the old gates had a functional design life that was older than that of some gates that are technically older,” he said. The new gates have a design life of about 50 years.
Schimpf explained that the reason for three lift gates originally, instead of two, was to deal with tailwaters of the upstream Lock and Dam 26 that Mel Price replaced, and that was demolished in 1990. “The upstream leaf of the old gate had not been used for years,” Schimpf said. With that lock gone, two lift gates are more efficient. The new gates included design features the old gates didn’t have, including special vents to let air out the bottom of the gates.
During the work at Mel Price, three other locks were also closed to allow miscellaneous repair work to be done. The closures were consolidated to lessen the impacts to industry of the closures. The 600-foot chamber at Mel Price remained open throughout the closure of the 1,200-foot main chamber.
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Featured photo caption: The second of two new lift gates waits on its barge at Melvin Price Lock and Dam in St. Louis, next to the crane barge that will lift it into place. (Photos by David Murray)
