<a href="https://en.wikipedia.org/wiki/Dredging" class="extiw" title="w:Dredging">Dredging</a> below <a rel="nofollow" class="external text" href="https://www.lrl.usace.army.mil/Missions/Civil-Works/Navigation/Locks-and-Dams/McAlpine-Locks-and-Dam/">McAlpine Locks</a>.
<p>Closeup of <a href="https://en.wikipedia.org/wiki/buoy" class="extiw" title="w:buoy">buoy</a> ( basically a metal <a href="https://en.wikipedia.org/wiki/Drum_(container)" class="extiw" title="w:Drum (container)">drum</a> ) used to mark location of dredge anchor.
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<a href="https://en.wikipedia.org/wiki/Ohio_River" class="extiw" title="w:Ohio River">Ohio River</a> mile 607.
<a href="https://en.wikipedia.org/wiki/Louisville,_Kentucky" class="extiw" title="w:Louisville, Kentucky">Louisville, Kentucky</a>.
July 24, 2002.
file # a2g088.
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IMG_0313.
</p>
Canon PowerShot A40 digital camera.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/70020260@N04">William Alden</a> from Louisville, Kentucky, USA
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/bill_alden/43111991571/">a2g088: Buoy used to mark location of dredge anchor</a>