The Waterways Journal
7 November 2005
By Katie Schulze
Ohio River traffic came to a halt in New Martinsville, W Va., when the primary lock chamber at Hannibal Locks and Dam, Ohio River Mile 126.4, was placed out of service due to a failure of a load hearing quoin seal on one of the lock gates.
The quoin seal provides a watertight seal between the lock gate and lock wall, but more importantly, it transfers the hydraulic load, or pressure of the water behind the lock, from the lock gate into the lock wall.
The auxiliary lock chamber was already out of service due to ongoing scheduled maintenance.
As a result, the Pittsburgh Engineer District has accelerated its repair efforts on the auxiliary lock and expected it to open by November 6. It is further estimated that the main lock chamber will remain closed for about two weeks while emergency structural repairs to the lock gates are completed.
At the time of the failure of the load bearing quoin seal on the upstream lock gate in the main lock chamber, the Pittsburgh Engineer Repair Fleet was placing the land wall emptying tainter valve and renovating its operating machinery as part of their ongoing scheduled maintenance of the auxiliary lock chamber. The valve repair work, necessary because of the general wear and deterioration, was originally scheduled to close for a 20-day period from October 22 through November 10.
To further compound the problem, the lower approach to the small chamber is silted in and must be dredged to allow loaded tows to enter or exist. Pittsburgh Engineer District Maj. Peter Steinig said two floating cranes are on site working two 10-hour shifts a day to correct the problem. Madison Coal & Supply Company is performing the dredging. Steinig said Madison Coal was able to secure empty hopper barges to further assist in the dredging. Steinig said the area was not expecting any severe weather in the area that would delay repair efforts.
"It currently ranges in depth from six to 10 feet in the first half mile of lower approach of the auxiliary chamber," he said. "It will be dredged to 12 feet universally."
In cooperation with the navigation industry, procedures have been developed to facilitate orderly and efficient locking of queued tows upon the reopening of the auxiliary lock chamber. As of 11 a.m. November 3, there were 26 tows awaiting passage through the Hannibal Locks - 18 upbound and 8 downbound.
The Hannibal locks average about 5,000 commercial lock-ages and pass more than 52 million tons of cargo annually.