Mile 43.0 — Pawnee Hills/Thebes Dome

John Ruskey

26 Apr 2026

2011 was a flood year. 12 months later the Mississippi River experienced extreme low waters that threatened to shut down shipping at Thebes due to the Thebes Domes. The Thebes domes rise from the bottom of the river here where the dolomite rock of the Pawnee Hills has been rounded into massive underwater summits. Normally far below the bottoms of passing tows and barges, 2011 exposed the vulnerability of navigation. The Army Corps responded in normal operating procedure by executing a platoon of heavy duty earth-moving machinery and tons of dynamite, TNT and plastic explosives t blow their way through the obstructions and open the passage.

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