Authorities traced the spill to a collision between a barge and a towing vessel between Baton Rouge and the Port of New Orleans, and shut down 65 miles of the Mississippi to "to avoid possible contamination of passing vessels and to reduce the amount of oil spreading further down the river."
About 31,500 gallons of oil flowed into the water as a result of the spill.
On Monday, the Coast Guard announced that it had reopened parts of the closed section, deployed oil booms to the affected areas. They also haven't received reports of oiled wildlife.
The lower Mississippi River has now officially reopened from mile marker 90 to 130, though it's still closed from 130 to 155.
"Our highest priorities in this response are the safety of the public and responders, and protection of the environment, said Coast Guard Cmdr. Rebecca Ore said in a statement.
Francis Hymel, director of emergency preparedness in St. James Paris, told the Los Angeles Times that most of the oil had stayed in the river, and not threatened the coastline.
“You hear 'oil spill' you think BP, Exxon Valdez. But this was a much smaller barge, not a spewing well,” he said. “The majority of it is being carried away by the current. It’s not that sludge washing up on shore. It’s a moving target.”