Navigating the Falls of the Ohio

Navigating the Falls of the Ohio. . , Before you is the McAlpine Dam, one of a coordinated system of 20 locks and dams on the Ohio River operated by the U.S. Army Corps of Engineers., The Dam: Maintaining River Depth , Prior to construction of locks and dams, the river depth varied considerably during seasons of the year. At times it was so shallow that people could walk across the river on the bottom. Snags and other obstructions made travel difficult and hazardous for boats. Dams create pools that are deep enough to assure safe movement of towboat traffic and pleasure boats. Each of the 20 dams on the river allows movement of boat traffic between pools., You are looking at the third dam built at this location, dating back to 1881. The current dam was built in 1961 and consists of five gates at the upper end and four gates downriver near the hydroelectric station., In addition to providing adequate water depth for navigation, the McAlpine Dam:,

Diverts water to the hydroelectric station., Has two 1,200' lock chambers through which millions of tons of cargo move annually.

, The dam does not, however, provide flood control., The Canal: A Safe Route Around the Falls , For boat traffic moving up and down the river, the Falls of the Ohio was the most dangerous navigation hazard on the entire 981-mile long river. During low water, the Falls were impassable. During high water, navigation was challenging and many boats wrecked in attempting to navigate the Falls., Locking Through , The drop in the river elevation at the Falls of the Ohio is 37 feet. The McAlpine Locks allow boats to go around the Falls., 1. When a boat goes up the river, the upstream gates (A) are closed and the drain valve (B) is opened. This allows the lock chamber to empty by gravity. The downstream gates (C) open and allow the boat to enter the chamber., 2. The drain valve and downstream gates are closed. Water enters through the opened fill valve (D) until it is level with water beyond the upstream gates., 3. The upstream gates open and the boat leaves the lock chamber to continue up the river. This procedure is reversed if the boat is going down river., [Captions:] , The snag boat E.A. Woodruff at work removing snags, boulders, and remains of boat wrecks along the river. , Photo from Clermont County Historical Society , Photo by Alan Goldstein