The Port of Beaumont in Texas and a section of the Neches River were closed after an oil spill from a pipeline.
An estimated 800 gallons of crude entered the river from the Jefferson Energy Terminal.
Authorities said the source of the leak had been secured and the US Coast Guard (USCG) was working with Texas General Land Office and Jefferson Energy to clean up the spill.
The deep-water port of Beaumont is located in southeast Texas at the mouth of the Neches River. In 2013 it was rated the fourth busiest port in the US.