The U.S. Army Corps of Engineers has reopened the main lock chamber to river traffic at Melvin Price Locks and Dam today after completing emergency repairs to one of the busiest locks on the Mississippi River.
The main 1,200-foot lock chamber at Alton was closed in late December due to a series of failures of the steel cables that hoist one of the lock's upstream lift gates, allowing the vessels to pass through the lock.
Mel Price Lock and Dam passes roughly 50 million tons of commodities annually, most of it grain headed for export. Other major cargoes include stone, chemicals, petroleum products and coal.
Three cable failures occurred since September, according to Andy Schimpf, a navigation manager for the Corps of Engineers' St. Louis district. The third failure occurred Dec. 28, and engineers determined that operating the leaf of the upstream vertical lift gate would be unsafe, prompting the closure of the lock.
An investigation determined that the cables failed as a result of severe corrosion near the connection point of the gate, an area which is always under water. Over time, corrosion caused individual strands of the cable to break until finally the entire cable severed.
New, stainless steel cables -- 108 assemblies in total -- were ordered to replace the galvanized cables. During the manufacturing and testing of the new cable assemblies, crews from the St. Louis district's Service Base and other locks converged on Mel Price Lock and Dam to perform as much needed maintenance as possible.
"While the main lock chamber was dewatered, our crews performed any repairs we could while we had access, and made sure that we would be ready to install the cables as soon as they were delivered," said Mike Quinn, a navigation manager for the Corps' St. Louis district. "We also increased inspections and monitoring of all the critical components on the 600-foot auxiliary lock to make sure it performed reliably and traffic could keep moving on the river."
The Mel Price lock is a key part of a national inland waterways transportation system and critical to the economics generated by the waterways. Barges move more than 566 million tons of cargo on the nation's inland waterways, creating an economic impact of more than $180 billion annually.