The route connects Marrero, an unincorporated suburb of New Orleans, with several small communities located along Bayou Barataria, including the town of Jean Lafitte.

It also provides access to the Barataria Unit of the Jean Lafitte National Historical Park and Preserve, a protected area of environmental and cultural significance which, among its many functions, features walking trails through its vast swamps and marshes.

Around 1980, a nine-mile (14 km) section of the route between Crown Point and Estelle was bypassed for through traffic in favor of the newly constructed LA 3134 (Leo Kerner/Lafitte Parkway, originally Lafitte-Larose Highway).

It follows Jean Lafitte Boulevard, an undivided two-lane highway that travels east for two blocks before turning north parallel to the bayou.

Over the next 2.7 miles (4.3 km), the roadway is flanked by small residences and boathouses lining Bayou Barataria on the west and a large body of water known as "The Pen" on the east.

[2][3][4] LA 45 proceeds along Jean Lafitte Boulevard as the road curves east with a section of Bayou Barataria that serves as a link in the Gulf Intracoastal Waterway.

A median divides the two lanes of traffic as the ramp makes a long loop back the north, and the highway ascends onto the Wagner Bridge, reaching a height of 72 feet (22 m) above the Gulf Intracoastal Waterway.

The surroundings become abruptly uninhabited as LA 45 enters the thickly wooded terrain of the Jean Lafitte National Historical Park and Preserve.

About 1.5 miles (2.4 km) beyond the junction with LA 3134, the highway passes the park's visitor center, which provides access to its many nature trails and other facilities.

LA 45 continues northward on Barataria Boulevard through the preserve for another two miles (3.2 km), at which point the highway passes through a floodwall and into a suburban area known as Estelle.

The remainder of the route varies from a rural minor collector through Jean Lafitte National Historical Park and Preserve to an urban principal arterial between Estelle and Marrero.

However, contemporary cartography by the United States Geological Survey shows no such road existing, and it disappeared from the above maps by the end of the decade in favor of the familiar alignment.

Since that time, a large section of the route between the Gulf Intracoastal Waterway and Estelle has been bypassed for through traffic in favor of LA 3134 (Leo Kerner/Lafitte Parkway).

The sole exception is a small portion connecting LA 3134 near Crown Point to the visitor center entrance of the Jean Lafitte National Historical Park and Preserve.