The Dam - The huge concrete wall that you see is the McAlpine Dam. Its main function is to control water levels for navigation, but its unusual shape, an elongated Z, also provides water for the hydroelectric station while keeping the fossil beds visible during periods of low water. All this is accomplished by opening or closing gates in the dam. There are 5 upper gates to your left, under the bridge, and four lower gates, down river, connecting to the hydroelectric station. Each gate is 22 feet high and 100 feet wide! The dam is over 30 feet high, but looks much smaller because it is about a half a mile away. The waterfalls in the dam are called castellations. They allow water to reach the wetland next to the dam even in the driest months, which is very important for maintaining plant and animal species. What you see today is he third dam built here. The original was constructed in 1881 and major renovations were made in the 1920's and in 1961.
Behind the dam you see the headwaters for the hydroelectric station. Boats are not allowed in this area because of the dangerous current near the turbines. The trees beyond the water are all on Shippingport Island. Once busy town, the island is now protected as part of the National Wildlife Conservation Area, with access by permit only. Beyond the island
is the Louisville and Portland Canal.
The Canal and Locks- As early as 1802, the expense and delay of hauling freight around the falls was so serious that several plans were proposed to overcome the obstacle. The Louisville and Portland Canal was begun in 1825 and the first boat passed through in 1830. Originally the canal was 1.9 miles long, 64 feet wide and had a total lift of 26 feet with a three flight lock system. Renovations over the years have resulted in a canal 500 feet wide and a 110' by 1200' lock chamber with a lift of 37 feet.
Construction is currently underway to build a second 110' x 1200' chamber to facilitate current and future commercial traffic The Ohio River carries 40% of the commercial water traffic in the continental U.S., according to the U.S. Commerce Department. In 2000, 55.8 million tons of products worth more than $12 billion passed through the canal. Coal, petroleum, grain, chemicals, iron and steel make up most of the tonnage.
The U.S. Army Corps of Engineers operates and maintains the McAlpine Locks and Dam.
For more information on the history of the area, visit the Falls of the Ohio interpretive center.