Lock failure at the Markland Dam closes river for 11 hours

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River traffic along the Ohio River was halted for nearly 11 hours on Sunday after a lock gate fell off at the Markland Dam and Locks near Markland.

The break took place on the west end of the lock system; and as the gate fell to the bottom of the Ohio River, an auxiliary gate had to be used so that traffic could reopen.

All traffic on the river was stopped in both directions at about 9 a.m., according to Army Corps of Engineers spokesman Todd Hornback said. By 8 p.m., the auxiliary lock was set up to start allowing the half-dozen blocked barges through.

The Ohio River is a major artery for shipping, with about 15 barges or ships using the locks on an average day. It is estimated that more than 50 million tons of cargo pass through the locks each year.

It was not known what caused the break at the Markland Locks and Dam. Officials from the Army Corps of Engineers are continuing their investigation of the accident, which came just one day after the Corps completed a 10-day inspection of the locks.

On Tuesday, Colonel Keith Landry, commander of the Louisville District of the Corps of Engineers, said that although the gates were well past their lifespan, there was no indication of imminent failure as the inspection was completed on Saturday.

New gate leaves have already been ordered for the locks.

They are scheduled to be delivered in June of next year; with installation in 2011 that will be part of an overall refurbishing of the locks.

The gate, which weighs 280-tons, broke off as a charter yacht from near Louisville was inside the lock. The break caused water to rush into the lock at a rate of one million gallons per minute.

The lock’s gates are 1,200 feet long and 110 feet wide. The smaller auxiliary lock is 600 feet long and 110 feet wide.

Going through the regular lock system normally takes about 30- to 45-minutes; but the auxiliary lock is expected to take around 90-minutes, which will slow commercial river traffic – but not stop it.

A lock is a section of a waterway, such as a river, that is closed off with gates. Vessels in transit enter the lock and the water level is raised or lowered in order to raise or lower the vessel to adjust to elevation changes.

One of the broken portions is known as a miter gate. The Corps of Engineers, on its website, says a miter gate “has two leaves that provide a closure at one end of the lock.” They are so named because the two leaves meet at an angle pointing upstream and resembling a miter joint, the Web site said, referring to a joint meeting at a 45-degree angle, such as the corner of a picture frame.

According to a story posted on cnn.com, a public policy organization, in a February 2008 report, graded the locks’ performance as a D, “based primarily upon risk of failure due to unreliability of miter gates.”

Cincinnati television station WCPO also reported on Sunday that the locks here will be closed for the next two weeks for another inspection.

On Sunday, witnesses reported that they heard an explosion of some sort at the locks, which led to speculation that terrorism was involved; but on Tuesday, Keith Landry said that what witnesses probably heard was the gate coming free – leaving a twisted hinge on top when it broke free.

Sonar equipment was brought to the site to try and locate the miter gate that broke off on Sunday morning and on Monday the gate section was located. The gate was photographed so that Keith Landry could decide whether or not there is sufficient space available to build a maintenance bulkhead in order to hold back the water.

As lock officials and the Corps of Engineers continues to develop a plan to deal with the situation; economics is also playing into the program.

It costs approximately $500 per hour to operate a tugboat, so the longer it takes to fix the gate; the longer trips for tugboats and barges are; which means the more money that operators and businesses are putting out to operate on a daily basis.