‘Catastrophic’ failure closes lock at Markland

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By Dave Taylor

Barge traffic is once again on the move after a structure failure at Markland Locks and Dam stopped traffic on the Ohio River early Sunday.

No injuries were reported after a miter gate on the downriver end of the main lock collapsed, according to Todd Hornback, a spokesman for the U.S. Army Corps of Engineers.

Traffic on the river was stopped in both directions at about 9 a.m. Sunday, Hornback said. By the time an auxiliary lock was put in service at 8 p.m., there were about six towboats with barges waiting to lock through.

An investigation is ongoing in an attempt to determine what caused the miter gate to collapse, a failure Hornback called a “catastrophic malfunction.” The north door of the gate became totally detached from the lock wall and sank into the river. Engineers were using sonar equipment in an attempt to locate the gate on Monday, he said.

The south door of the miter gate was also damaged, according to Gary Birge, Markland lockmaster. “It has a broken anchorage at its hinge point,” he said.

According to The Corps of Engineers’ web site, a miter gate “has two leaves that provide a closure at one end of the lock.” The two leaves meet at an angle pointing upstream and resemble a miter joint, hence the name.

Birge said the failure occurred when employees “went to close the gate. Water in the flow-through chamber took the gates out.”

The main lock is 1,200 feet long and 110 feet wide. The auxiliary lock is 600 feet long and 110 feet wide. The locks are used to raise and lower chamber water levels to enable boats to navigate between the upper pool water level of 455 feet, and the 420-ft lower pool level.

While lockage for river navigation is continuing through the auxiliary lock, the process is much slower due to the shorter lock channel, Birge said, because of the process of “double lockage.”

“Normally, a tow and barges can lock through the longer lock in a one-step process,” Hornback said, “but with the auxiliary lock it’s a two-step process.”

Now, a tow must uncouple half the load and anchor those barges to the riverbank or the approach wall, Hornback said. Leaving the anchored load, the tow takes the other half through the lock and anchors it on the other side of the dam, then returns to lock-through the remaining half. The two halves are then re-coupled and the tow resumes its trip with the full load.

“Instead of 30 to 45 minutes to lock through, the process now takes about 90 minutes,” he said. “Sometimes an assisting towboat may be available to take half the load through and save some time. It’s going to take more time to lock through, but we’re keeping the river open.”

An estimated 55 million tons of commodities pass through the Markland Locks each year, according to Waterways Council Inc., a public policy watchdog organization. Coal, which fuels numerous electric power plants along the Ohio River, is the number one commodity transported annually.

Waterways Council, in a February 2008 report, had graded the performance of the locks at Markland as a D.

“The risk is very high that a failure of the lock gates will occur, forcing traffic through the auxiliary lock for an extended period, causing huge delays and costs to the towing industry,” the council said in the report.

Hornback said the federal government recently allocated $10.6 million to install new chamber miter gates, a process that was to be completed in 2011.

“They had already begun the design and fabrication” of the new gates, according to Hornback, “and we were expecting materials to be delivered to the site by June of 2010 with installation sometime in 2011.” The weekend collapse of the miter gate “may or may not impact that schedule,” he said.