Falls of the Ohio, Portland Canal and McAlpine Locks and Dam with upper and lower gates labelled
The dam is mostly fixed weir now, but there are five Tainter gates at the upper gated structure, and the bear traps (a type of movable dam) of the earlier dam have been replaced by four Tainter gates at the lower gated structure.
There are now two 1200-foot locks at McAlpine, the newest one having opened in 2009.

Ohio River miles 604-608
Louisville, Kentucky

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