Locks and Dam 14 is four miles below LeClaire, Iowa, and 493.3 miles above the confluence of the Mississippi and Ohio rivers. The site if also 3.6 miles below the head of the notorious, rock-bedded, Rock Island Rapids. The LeClaire Lock, opened in 1940, and the remains of the LeClaire Lateral Canal, built in 1921-1924 to bypass this treacherous stretch of river, are located along the Iowa shores.