(AP) -- AT PASS A LOUTRE, La. - A chocolate-brown blanket of oil about as thick as latex paint has invaded reedy freshwater wetlands at Louisiana's southeastern tip, prompting Gov. Bobby Jindal to step up calls Wednesday for building emergency sand barriers.
Jindal and Plaquemines Parish President Billy Nungesser led a flotilla of media to inspect the oil encroaching on remote wetlands lining Pass a Loutre, near where the mouth of the Mississippi River empties into the Gulf of Mexico.
Oil from the Deepwater Horizon offshore rig disaster had been lapping at the coast before. But this was not the light rainbow sheen or the scattered tar balls seen in previous days.
Jindal, sitting at the edge of an airboat, swept a handheld fishing net through the mess and held it up. It was coated with brown sludge, which had stained the lower shafts of the leafy green reeds sticking up to eight feet out of the water.
"This has laid down a blanket in the marsh that will destroy every living thing there," Nungesser said.
Jindal said there had been indications of such coastal contamination from aerial observations on Tuesday. Wednesday's trip confirmed the incursion.
"The day that we've been fearing is upon us today," he said later at a news conference in the coastal town of Venice, about an hour away by boat.
Nungesser said the blanket of oil has extended into marshes at Pass a Loutre, North Pass and South Pass, near the river's mouth, He said it's proof that containment booms and dispersants aren't enough to save Louisiana wildlife and the economy of commercial and recreational fishing that depend on it.
Jindal and Nungesser said they are awaiting approval from the U.S. Army Corps of Engineers for an emergency dredging permit to dredge sand from nearby areas for the construction of a line of sand berms-in effect, a series of new barrier islands-40 miles on either side of the river. The berms would block the oil, they said, and the new, man-made beaches would be much easier to clean than the marshes that teem with plant life.
Neither official was certain what was holding up approval of the proposed dredging project.
A telephone call to the Corps for comment was not immediately returned.
On the forward lines of the spill Wednesday, an armada of shrimp boats and other vessels were stringing lines of absorbent boom to soak up the oil, hoping to shield the fragile marsh. But just outside South Pass, at the mouth of the Mississippi River, thousands of yards of shoreline remained exposed to a thin, intermittent sheen rolling in with each successive wave.
At the water's edge, the oil is soaked several inches deep into the tangled, marsh-grass roots that hold Louisiana's coastline together. Small crabs, spotted with crude, skittered among the roots and oil-covered garbage that washed in with the tide.
Farther in, rust-colored globs oozed from puddles and wrapped around the bottom of the plant stalks. Where it was thickest, the stalks bent to the water under the oil's weight.
So far the spill appears to have reached only the very edge of the marsh, a vibrant estuary that shelters dozens of species of fish, birds and mollusks, at South Pass. But over the last several days, it has inched inland.
"It's moving farther up and it's accumulating," said Lauren Valle, a Greenpeace volunteer who has been shuttling members of the media to affected areas aboard one of the environmental group's boats.
Valle said she had been turned away from some areas by BP contractors. "They're trying very hard for people not to see it. We're here to bear witness."
Associated Press Writer Matthew Brown contributed to this report from South Pass, La.
WATCH: Louisiana Governor Bobby Jindal: "This was the day everybody was worried about"
WATCH: New Orleans' WWL reports that grass will die in affected wetlands within 5-7 days. Plaquemines Parish President Billy Nungesser scolds Army Corps of Engineers for not approving Louisiana's emergency request to build barrier islands that would protect wetlands from oil.
The Morning Email helps you start your workday with everything you need to know: breaking news, entertainment and a dash of fun. Learn more