Louisiana Highway 3146 (LA 3146) was a state highway that served St. Bernard Parish. It spanned 0.56 miles (0.90 km) in a west to east direction along Colonial Boulevard in Violet. It was a temporary connector between the original and current routes of LA 39 in the 1970s and 1980s.
In 1975, LA 39 was re-routed onto a newly opened extension of Judge Perez Drive from LA 47 (Paris Road) in Chalmette to a dead end at the Violet Canal, pending construction of a further extension from Violet to Poydras. During this time, traffic was routed onto Colonial Boulevard to connect the end of the new LA 39 (East Judge Perez Drive) with the existing LA 39 (East St. Bernard Highway, now LA 46). The Violet Canal bridge and extension of Judge Perez Drive to Poydras was opened in 1981, and LA 3146 was deleted sometime afterward.