Bayou Lafourche, originally called Chetimachas River or La Fourche des Chetimaches, (the fork of the Chitimacha), is a  bayou in southeastern Louisiana, United States, that flows into the Gulf of Mexico. The bayou is between Louisiana Highway 1 on the west, and Louisiana Highway 308 on the east and is known as "the longest Main Street in the world." It flows through parts of Ascension, Assumption, and Lafourche parishes. Today, approximately 300,000 Louisiana residents drink water drawn from the bayou.