Navigation Conditions at LaGrange Lock and Dam, Illinois Waterway. Hydraulic Model Investigation

LaGrange Lock and Dam are located on the Illinois River at river mile 80.2, 8 miles downstream from the city of Beardstown, IL. The model investigation was concerned with alleviating some problems of the wicket dam by replacing some of the wickets adjacent to the lock with a submersible tainter gate. The tainter gate would regulate the navigation pool under normal conditions and could be submerged to pass heavy ice flows. The tainter gate eliminates the need for using the wickets for pool regulation, therefore greatly reducing the raising and lowering of the wickets. The model investigation was necessary for evaluation of the effects of the proposed tainter gate on navigation conditions, water-surface slopes through the reach, and the potential for scouring of the channel downstream of the proposed tainter gate.