Officials had previously found two leaks in the riser, the 5,000-foot-long pipe that connected the rig to the wellhead and is now detached and snaking along the sea floor.
In a hastily called news conference, Rear Adm. Mary E. Landry of the Coast Guard said a scientist from the National Oceanic and Atmospheric Administration had concluded that oil is leaking at the rate of 5,000 barrels a day, not 1,000 as had been estimated.
low-lying wet land with grassy vegetation; usually is a transition zone between land and water
Part of the oil slick was only 16 miles offshore and closing in on the Mississippi River Delta, the marshlands at the southeastern tip of Louisiana where the river empties into the ocean.
Already 100,000 feet of protective booms have been laid down to protect the shoreline, with 500,000 feet more standing by, said Charlie Henry, an oil spill expert for the National Oceanic and Atmospheric Administration, at an earlier news conference on Wednesday.
