After a short distance, the route begins to travel along the west bank of Bayou Teche.

Continuing northward, LA 31 makes a jog in the tiny community of Parks and follows a western bend in Bayou Teche.

Access to the interstate is instead provided by LA 328 on the opposite bank of Bayou Teche.

LA 31 continues to meander along several bends in the bayou, passing opposite Cecilia en route to Arnaudville.

The highway turns due west, enters the city limits of Opelousas, and passes through a diamond interchange with I-49.