A cofferdam on the Ohio River near Olmsted, Pulaski County, Illinois, USA. The cofferdam was constructed by the U.S. Army Corps of Engineers for the purpose of constructing the <a href="https://en.wikipedia.org/wiki/Olmsted_Locks_and_Dam" class="extiw" title="en:Olmsted Locks and Dam">en:Olmsted Locks and Dam</a> on the Ohio River.
U.S. Army Corps of Engineers, photographer not specified or unknown
U.S. Army Corps of Engineers Digital Visual Library<br><a rel="nofollow" class="external text" href="http://images.usace.army.mil/images/Hires/Celrl127.Jpg">Image page</a><br><a rel="nofollow" class="external text" href="http://images.usace.army.mil/scripts/PortWeb.dll?query&amp;field=Image%20name&amp;opt=matches&amp;value=Celrl127.Jpg&amp;template=Selected_Info&amp;catalog=photoDVL">Image description page</a><br><a rel="nofollow" class="external text" href="http://images.usace.army.mil/">Digital Visual Library home page</a>