The McAlpine Locks and Dam is located on the Ohio River 604.5 miles below Pittsburgh, Pennsylvania, at the northwestern end of Louisville, Kentucky, in the Portland neighborhood. The navigation locks are located on the Kentucky side of the river at mile 606.8. The upper pool extends approximately 75 miles to the Markland Locks and Dam.
The project was approved by the Secretary of Army on November 8, 1955, under authority of Section 6 of the Rivers and Harbors Act approved March 3, 1909.
The Falls of the Ohio are located at Louisville, Kentucky, and are the only falls in the entire length of the Ohio River. They consist of a rock reef extending across the river and forming a rapids having a length of about 3 miles. The low water slope in this distance is 26 feet and the falls or rapids in their natural state were impassable by vessels except at high stages.
As early as the year 1802, the expense and delay attending the reshipment of freight around the falls had become so serious that numerous plans were proposed for overcoming the obstruction. No active measures were taken until 1825, when the Louisville and Portland Canal Company obtained a charter from the Commonwealth of Kentucky. This charter authorized the company to construct a canal around the Falls of the Ohio within the State of Kentucky.
The canal was completed and the first boat passed through December 22, 1830. As originally constructed, the canal was 1.9 miles long, 64 feet wide, and had at its lower end a 3-flight lock with a total lift of 26 feet. Each chamber was 198 feet long between miter posts, with available length of 185 feet, a width of 50 feet, and a lift of 8.7 feet. The canal had a depth of 3 feet at low water stage. At the time the canal was completed, its dimensions were thought to be sufficient for all time, but by 1852 only 57 percent of the craft in use on the western waters could pass through the locks. In June 1874, the War Department, Corps of Engineers, assumed the supervision of navigation. In 1880, navigation was made free of any traffic charge. Various improvements and alterations were made until they culminated in a combined navigation and hydroelectric development. This development was completed in the 1920s, and formed an integral part of the canalization of the Ohio River.
The lock numbering system was established about 1914 and the project at Louisville became Locks and Dam 41. On May 24, 1960, the name was changed officially to McAlpine Locks and Dam in honor of W.H. McAlpine, former Louisville District Engineer, during the years 1917-1918. He is the only civilian employee to hold this position since the Louisville District was established in 1886.
In the 1960s, the canal was widened to 500 feet, the 1200 foot lock was built, and the present dam was constructed.
The Water Resources Development Act of 1990 authorized the McAlpine Locks Replacement Project. This work replaced the 600’ and 360’ locks with a 1200’ x 110’ lock on the Kentucky bank side of the Louisville and Portland Canal adjacent to the existing lock. This gave the McAlpine project twin 1200 foot locks for efficient movement of projected increases in tow traffic. In addition, the existing swing and bascule bridges were replaced by construction of a two-lane, high fixed span concrete bridge to provide access to Shippingport Island and the Louisville Gas and Electric hydroelectric generating station. The new lock was completed and opened April 2009.
Falls Of The Ohio National Wildlife Conservation Area
PL 97-137, passed by the U.S. Congress in 1982, designated the fossil beds and falls area as “The Falls of the Ohio National Wildlife Conservation Area.” Responsibility for operation and management has been vested in the Louisville District. Click here for more information.