Yalobusha Dive Team Helps Extract Broken Chain At Grenada Spillway
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By John Beshears
The Coffeeville Courier
GRENADA LAKE – Yalobusha County EMA Director Stewart Spence was contacted by the Grenada Lake Corps of Engineers office for assistance with a retrieval effort in the Grenada Lake spillway last Tuesday, Feb. 21.
The “chain” that lifts and lowers the main flood gate in the Grenada spillway house broke and needed to be removed from the spillway. The chain was thought to be in the concrete area from the end of the wing walls back toward the outlet channel. There was almost 30 feet of chain missing and removal was essential. The chain trapped in this section of the outlet channel would roll and tumble, eating away at the concrete from the force generated by water released through the spillway. There are several concrete breakers and a concrete wall that breaks up the force of released water to reduce erosion. The blocks and wall are essential to successful operation of the dam.
The Yalobusha County Dive Team made their first trip to the spillway on Tuesday, Feb. 21, but it was determined that there was too much current in the river channel to attempt the dive. The team went back for a second attempt the next day. Divers Stephen Spence and Will Burns were unable to locate any parts of the chain.
Thursday morning, under the direction of Yalobusha County EMA Directors Spence and Jarred Logan, another attempt was planned. Divers Tony Vaughn and Wesley Gholson, both from the Lafayette County Dive Team, were able to locate and retrieve 21 rollers from the chain, but could not find any large pieces of the once 30 foot chain. It was estimated that there were 90 rollers in the section of broken chain, leaving around 70 still in the spillway.
Grenada Lake Manager Chris Terry thanked them for their help and put a call in to the Vicksburg office for further instruction on how to proceed. The decision was made to construct a cofferdam below the wing walls and pump the water out between it and the outlet. This will let them recover all of the stainless steel chain and remove the threat of damage to the outlet channel.
Each roller in the chain weighs around 12 pounds, and there are three rollers per foot of chain.