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McAlpine Locks and Dam


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.

NOTICE: The Fisherman's Access Trail located along the western bank of Shippingport Island within the Falls of the Ohio National Wildlife Conservation Area will reopen to the general public on Saturday, May 27, 2023. Access will be allowed from 7 am - 6 pm April through September and 7 am - 5 pm October through March. Increased patrols will be carried out by the Locks & Dams Natural Resources Specialist and closing times will be strictly enforced.

Educational programs or scientific research may be granted through a Special Activity Permit. Requests should be submitted to the Locks & Dams Natural Resources Specialist at Permit fees may be collected on a case-by-case basis. Per the Engineer Regulation 1130-2-553, Chapter 9 Recreation Use Fees, .11. Special Use Permit Fees, "a Special Use - Activity Permit Fee may be charged to cover the administrative cost of the program. In addition to the Permit Fee, a use fee may be charged to recover costs incurred by the Corps, to manage the permit program, as determined by the Operations Project Manager. These costs may vary depending on the permit type that is issued."

Visitor Information

The McAlpine Locks and Dam Visitor Area is located at 805 North 27th Street, Louisville, KY 40212. From I-64 West, take the 22nd Street Exit. At the bottom of the ramp, turn right onto Northwestern Parkway. Head straight and turn right onto 27th Street.

There is a small metal sign "McAlpine Locks and Dam" at 27th Street. Follow the road to the right and go through the levee and across the railroad tracks. Please watch for pedestrian and bike traffic along the Riverwalk. Follow the signs to the visitor area. McAlpine is accessible via the Louisville Riverwalk.

At the outdoor interpretive center, there are recorded audio messages - a self-guided tour - about the locks and dams, navigation and history of the area at kiosks along the cantilevered pavilion that extends out over the lock chamber. You may see barge tows passing through. No other parcels of the island are open to the public nor is picnicking permitted at the fishing area parking lot.

Locks and Dams

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Ohio River

Markland Locks and Dam
2760 US 42 West
Warsaw, KY 41095
(859) 567-7661

McAlpine Locks and Dam
805 North 27th Street
Louisville, KY 40212
(502) 776-6866

Cannelton Locks and Dam
5281 E. State Road 66
Cannelton, IN 47520
(812) 547-2962

Newburgh Locks and Dam
6877 State Road 66
Newburgh, IN 47630
(812) 853-8470

John T. Myers Locks and Dam
16501 Raben Road
Mt. Vernon, IN 47620
(812) 838-5836

Smithland Locks and Dam
1401 Smithland Dam Road
Brookport, IL 62910
(618) 564-2315

Olmsted Locks and Dam
567 New Dam Road
Olmsted, IL 62970
(618) 748-6400


Green River

Green River 1
5048 Dam and Lock Road
Reed, KY 42451
(270) 826-7360

Green River 2
695 W. 1st Street
Calhoun, KY 42327
(270) 273-3152

Lock Information

Canal 10,200'
 Existing Lock 110’ x 1200’
 Existing Lock 110’ x 1200’

Dam Information


Concrete fixed
weir with tainter

Length 8,627'
Upper pool 420'
Lower pool 383'
Number of gates 9
Height of gates 22'
Width of gates 100'