[15] The route's mileposts increase from the northern end contrary to common practice.

Louisiana Highway 1015 (LA 1015) consists of two road segments with a total length of 1.42 miles (2.29 km) that are located in the Assumption Parish community of Pierre Part.

Louisiana Highway 1016 (LA 1016) consists of two road segments with a total length of 6.49 miles (10.44 km) that are located around the Assumption Parish community of Belle River.

[22] The route's mileposts increase from the northern end contrary to common practice.

Louisiana Highway 1018 (LA 1018) consists of two road segments with a total length of 0.16 miles (0.26 km) that are located in the Catahoula Parish village of Harrisonburg.

[25] The route is bannered in all four cardinal directions with the signage changing from north–south to east–west at Watson.

Louisiana Highway 1020 (LA 1020) runs 2.00 miles (3.22 km) in a north–south direction along Bend Road from LA 1019 west of Watson to a dead end near the Amite River northwest of Watson.

[34] Though signed in the field, the concurrency with LA 1026 at its western end is not included in the official route mileage, resulting in a slightly shorter figure of 0.31 miles (0.50 km).

[37] The route is bannered east–west and is an undivided two-lane highway for its entire length.

Louisiana Highway 1030 (LA 1030) runs 0.43 miles (0.69 km) in a general north–south direction along Cockerham Road from the Denham Springs city limit to a junction with LA 1026 northeast of Denham Springs.

[39] The route formerly extended further west along Cockerham Road into Denham Springs to LA 16, but this portion was deleted from the state highway system in 2017 as part of La DOTD's Road Transfer Program.

Louisiana Highway 1037 (LA 1037) runs 8.764 miles (14.104 km) in a general east–west direction from a point north of Tickfaw State Park to a point on the Natalbany River in Springfield.

Louisiana Highway 1038 (LA 1038) runs 0.91 miles (1.46 km) in a northeast to southwest direction along Carter Cemetery Road from an intersection with a local road southwest of Springfield to a junction with the concurrent LA 22/LA 1037 inside the corporate limits.

[51] The route is bannered east–west, and its mileposts increase from the eastern end contrary to common practice.

[52] The route's mileposts increase from the northern end contrary to common practice.

LA 1039 heads east on Black Lake Club Road from a point near Easterly Lane and proceeds to the tiny community of Denson.

Here, the highway turns north onto Bear Island Road and continues to the junction with LA 22 near Maurepas.

[53] The route begins at a point on LA 43 located just north of I-12 (exit 32) between Hungarian Settlement and Albany.

After curving to the northeast, LA 1040 crosses over without intersecting I-55, simultaneously entering the city of Hammond.

The route curves due east onto Chauvin Road, widening to accommodate a center turning lane, and terminates shortly afterward at a junction with US 51 (South Morrison Boulevard).

The route became LA 1040 in the 1955 Louisiana Highway renumbering[55] and has remained largely the same to the present day apart from a small realignment on its eastern end.

[56][57] LA 1040 originally followed the entirety of Old Baton Rouge Highway to its intersection with US 51.

However, this intersection, located only 300 feet (91 m) south of the junction of US 51 and US 190, was a source of traffic congestion.

[59] The route's mileposts increase from the eastern end contrary to common practice.

Louisiana Highway 1048 (LA 1048) runs 4.98 miles (8.01 km) in an east–west direction from LA 1047 southeast of Greensburg, St. Helena Parish to the concurrent US 51/LA 10 north of Roseland, Tangipahoa Parish.

Now heading eastward, LA 1048 passes through a diamond interchange with I-55 (exit 50), connecting with Hammond, Louisiana to the south and Jackson, Mississippi to the north.

The highway proceeds a short distance further to a T-intersection with US 51/LA 10 at Arcola, a point just north of Roseland.

The highway enters the Kentwood city limits on Collis B. Temple Sr. Road, passing under without intersecting I-55.