The Coast Guard and other emergency agencies are responding to an oil spill at mile marker 667 on the Intracoastal Waterway near Port Isabel after 20,000 gallons of diesel spilled into the water on Tuesday night.
The Coast Guard says a towing vessel called Capt. Jim Green hit a dock and released the low-sulfur fuel just before 11:30pm.
Authorities are investigating what caused the collision.
The Coast Guard, Texas General Land Office and Kirby Inland Marine is responding to the scene.
Miller Environmental, an oil spill response organization, is currently on scene conducting air monitoring and oil recovery operations. The source of the spill has been secured, the Coast Guard says.
Authorities say there have been no reported impacts to wildlife at this time.
"We were immediately notified by the crew of Jim Green and responded quickly with our partners at the Texas General Land Office," said Capt. Tony Hahn, commander, Sector Corpus Christi. "We will be assessing the impacted areas quickly and will ensure a robust and thorough cleanup."
The Coast Guard says it is working to assess the impact on the waterway and surrounding areas. The Coast Guard is also issuing a safety marine information broadcast every hour.