Tuesday, July 31, 2018
Locks and Dam 52, Part 1: Its Days Are Numbered
Locks and Dam 52 has done its job for the past 90 years or so, but its time is over.
Officials from the U.S. Army Corps of Engineers and executives from companies that operate towboats or companies that ship product by water can give you the numbers of why they need the new Olmsted Locks and Dam completed, but sometimes you have to see and hear things for yourself to get a full understanding of what they're saying.
That was what I did last week while on a media tour of Olmsted organized and sponsored by the Waterways Council Inc. Speakers talked of the need to complete Olmsted and retire 52 (more on that later). The seasoned journalist in me wanted more, so I asked the commander of the Corps' Louisville District if I could be allowed access inside the security zone at 52 to see for myself what the problems are. She said that would be no problem, so when everyone else had left for home, I headed for Brookport, Ill., to visit Locks and Dam 52.
It was the first time I had been there since 1986, and things had changed. At that time, the temporary lock was still in service and the dam looked to be in good condition. But 32 years and 23 days later, it was clear that age had been hard on the old dam and the locks.
You could hear some of the operating equipment groaning like an animal in pain every time it was put in use, and you could hear a rhythmic banging coming from somewhere out in the river. Parts of the dam were missing, too.
First some facts. Part of the following information came from two YouTube videos produced by the Corps. You can find them here and here. Part is from other research I have done on the old Ohio River dam system out of personal interest.
Locks and Dam 52, formerly Lock and Dam 52, was completed in 1929, the same year as the similar Lock and Dam 53 (now Locks and Dam 53). They were the last two dams in the system authorized by Congress in 1909. Some of the old dams were planned and under construction before 1909.
The completion of dams 52 and 53 brought to an end the process that began when the Davis Island Lock and Dam went into operation near Pittsburgh in 1879 — 50 years earlier. That process was to make the Ohio navigable year-round regardless of drought.
Locks and Dam 52 is 2,998 feet long. It consists of the original lock that measures 110 feet wide by 600 feet long. That was the standard Ohio River lock length in the early 20th Century. In 1969, a temporary lock 1,200 feet long was added. The lock received the Corps' Chief of Engineers Award for its innovative technical features. It was designed to have a service life of 10 years. It's approaching its 50th anniversary.
The temporary lock was made of circular cells of sheet steel filled with concrete. Corrosion, wear and impacts from barge hits have damaged them over the years and now threaten their structural integrity. Some cells have split open, requiring the lock to be closed for repairs. In addition, the lock's filling and emptying valves have deteriorated, too.
The old 600-foot lock likewise has deteriorated with age.
The dam maintains a navigation pool of 302 feet above mean sea level for 20.5 miles up the Ohio to the Smithland Locks and Dam and on the lower parts of the Tennessee and Cumberland rivers, both of which empty into the Ohio a few miles above 52. When Dam 53 is raised, Dam 52 provides a 12-foot lift.
The dam consists of a navigable pass that is 1,248 feet long. It also has a Chanoine weir that is 160 feet long, three beartraps of 91 feet each to help regulate the river level and a fixed concrete weir of 725 feet.
The dam consists of 487 wickets made of oak. Each is four feet wide, and they are up to 20 feet long. They are raised and lowered manually to maintain the pool at 302 feet. Raising them is a hazardous job that takes 12 to 16 hours to accomplish and must be done regardless of weather. After nearly 90 years of service, the wickets and their cast iron frames are aging and require constant maintenance. As of July 25, several were missing or not in use.
Repairs to the wickets are done two at a time by divers working behind a shutterbox to protect them from the river current.
Shutdowns of the lock because of mechanical problems or because of problems with the dam are frequent, and on many days there is a line of boats waiting to use the lock.
Up next: More images from Locks and Dam 52.
Postscript: My thanks to Col. Antoinette Gant, commander of the Louisville District, to Wayland Humphrey, director of operations transition for the Louisville District of the Olmsted project and the district's public affairs staff for allowing the visit. Also to Deb Calhoun, senior vice president of the WCI, for arranging the media tour and sponsoring it. And to the various industry speakers who will be quoted about their problems with 52 in posts coming soon.
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