JUDY WOODRUFF: In the Gulf of Mexico today, retired Coast Guard Admiral Thad Allen warned, a storm system may move into the area this weekend. That means BP might have to stop testing the cap on its blown well and let the oil resume flowing.
Meanwhile, local authorities and federal scientists are butting heads over how to block the oil that's already spilled.
"NewsHour" correspondent Tom Bearden has a report from Grand Isle, Louisiana, on how this is playing out in a bay along the coast.
TOM BEARDEN: Massive amounts of oil flowed into Barataria Bay in late May, contaminating marshes, beaches, and wildlife breeding grounds.
Local and parish officials had seen it coming, asked for help, and didn't get it. So, they took matters into their own hands. BP had hired some 50 local fishing boats to help with the cleanup, but hadn't given them any orders.
Jefferson Parish officials used a state law to commandeer the boats and put them to work picking up oil.
Deano Bonano is the parish's emergency director.
DEANO BONANO, Jefferson Parish, Louisiana, emergency director: Within an hour, our fire and police men and had it organized and had those boats on the move and were attacking the oil coming onshore.
TOM BEARDEN: That effort was a start, but wasn't enough. So, state local and state officials are now lobbying for something much bigger.
Manmade stone jetties like these protect the entrances to marinas all over the world. City fathers here in Grand Isle, Louisiana, believe the same approach, scaled up dramatically, might keep a great deal more oil from entering Barataria Bay, one of the best fisheries in the country.
They want to build two rock walls, each nearly 7,000 feet long, to help narrow the entrances to the bay. But federal government officials so far have denied that request because they say it would cause too much environmental damage.
Federal biologist Patti Holland says a rock wall would try to force too much water into too narrow a space.
PATTI HOLLAND, biologist, U.S. Fish and Wildlife Service: From the Fish and Wildlife Service'S standpoint, we're concerned that the rock barrier will neck down the passes to the point where the velocity of water going through the pass will cause tidal scouring and possibly cause breaching in the islands, because the water is going to want to go to the place of least resistance. And, when it does that, it could blow through an island.
TOM BEARDEN: But Governor Bobby Jindal says that risk is hypothetical. The oil is not.
GOV. BOBBY JINDAL, (R-La.): Yes, I will say it again. Rocks in the water are much more preferable than oil in the water. That oil is doing a lot more damage to Barataria Bay. And I wish the folks in D.C. could smell the oil, touch the oil, see what it's doing to Barataria Bay, the Gulf's nursery.
TOM BEARDEN: After the wall was rejected, state and local officials once again took matters into their own hands.
DEANO BONANO: Because the Corps of Engineers wouldn't give us an approval for our rock barrier plan, we have stacked barges on a 45-degree angle coming from the east, heading towards the Northwest, to actually steer oil as it comes into this 7,000-foot opening. We're going to narrow that down to less than 1,000 feet.
TOM BEARDEN: The principle is pretty simple. Incoming currents are channeled into an area ringed with heavy booms made from steel pipe, where any oil can be skimmed up. It's working, but Bonano says a wall made of rocks would provide protection in a storm, something the barges can't do.
DEANO BONANO: The barges have to be moved every time there's a threat of a storm. It takes us days to get all this stuff out of here. Every time there's a threat in the Gulf, we're gong to have to move these barges and these pipe booms, pull them out, and bring them back to Grand Isle. And oil -- any oil in the area is going to be free to go in and out of the estuary. The rocks don't have to be moved.
TOM BEARDEN: Bonano says the wall would also be cheaper, about $16 million. Currently, the barge operation costs $30 million a month.
But Holland says the water that would be rechanneled might not only damage the barrier islands, but could also rupture oil pipelines in the bay.
PATTI HOLLAND: There's a lot of pipelines that go through these passes. And if we increase tidal scouring, then we could potentially have another oil spill on our hands. And that's the last thing we would like to happen.
TOM BEARDEN: Bonano has been holding a series of meetings with groups of scientists, hoping to come to an agreement.
DEANO BONANO: We challenged them. Don't tell us just, no, this is a bad idea. You tell us, as scientists, how we can modify this project to address your concerns of the effects on the estuary, and yet still protect it from the oil. That's the challenge we have gone back to them with.
TOM BEARDEN: Dr. Ioannis Georgiou is one of the scientists who reviewed the application. He says scientists want to help. They just need more time.
IOANNIS GEORGIOU, University of New Orleans: I understand the emergency situation, and I don't disagree. I agree that this is an emergency situation. And we have to do something. What I don't know, have all the -- or any alternatives have been explored that are perhaps easier to implement?
TOM BEARDEN: But Governor Jindal says the time to act is now. And he says the wall could be removed when the threat of oil is past.
GOV. BOBBY JINDAL: Some folks express concern about the permanent placement of rocks and the unintended consequences. Let's be very clear. Even in the last submission, the state required them to -- to make the rocks temporary. In the fourth plan they are now submitting, BP has agreed to fund -- to advance-fund the removal of those rocks. Look, the rocks are there on the barges. They are waiting to go. Let's go ahead and get this done.
TOM BEARDEN: The bay has received something of a reprieve. No new oil has arrived in about three weeks. But this is the height of the hurricane season, and everybody is keeping a wary eye on the Gulf, hoping that predictions of above-average hurricane activity will turn out to be wrong.