MOBILE, Ala. -- Thirty-one miles long, 10 miles wide and no deeper than 10 feet or so where it isn't dredged, Mobile Bay resembles a big, shallow bathtub. The nation's 9th-busiest seaport lies on one side, multimillion-dollar homes stand on the other and a broad pass at the bay's mouth leads directly to the Gulf of Mexico, where a massive oil spill is slowly spreading.
Because of that geography and the bay's slow-moving currents, protecting it from being inundated with oil is trickier than keeping the Gulf spill away from New Orleans, which sits a safe 120 miles upstream from the mouth of the Mississippi River. It's a mission that took on extra urgency Saturday when oily blobs started arriving at Dauphin Island, which guards the entrance to the bay.
Yet Alabama officials believe they've found a solution as simple as a barn gate to guard the crucial passage, scene of one of the Civil War's most famous battles.
Drawing on a concept that goes back to the early days of river navigation, Alabama officials are using oil-blocking booms to construct what amounts to a lock system at the bay's mouth, which is four miles across.
Pilings are being driven into the bay's squishy bottom, and two gates will be attached once they're in place. If oil gets to the mouth of the bay -- and officials believe it will if the spill isn't plugged off Louisiana's coast -- ships will enter through the first gate, get a scrubbing, and exit through the second.
Separately, on the western side of the bay, booms are supposed to keep oil from entering the bay from the Mississippi Sound. Previous barriers in the same area were swamped by rough seas, but officials hope securing them to the pilings of a 3-mile bridge to Dauphin Island will make a difference.
Nicole Reed hopes the work pays off. She's already nervous about the water quality in Mobile Bay, and the sight of dead catfish rotting on the shore as oil swirled miles away was enough to convince her to keep her two preschool daughters out of the bay near their home in Fairhope, on the high-dollar eastern shore.
"I don't think there's any way they can say the oil won't get up this far, and that's scary," said Reed.
The stakes are just as high for Jimmy Lyons. As director and CEO of the Alabama State Port Authority in Mobile, he runs the nation's ninth-busiest port based on shipping volume. He thinks most anything is worth a try at this point.
"You can get some dicey conditions at the mouth of the bay with winds and currents and swells. Maybe the pilings they are putting up will hold it together," he said. The gating and cleaning process should take about two hours, Lyons said, which isn't much compared to the cost of shutting down a port or cleaning up oil.
These waters have known drama since as far back as 1864, during the Battle of Mobile Bay.
Faced with a force that included a feared Confederate ironclad and a field of submerged explosives, Union Adm. David Farragut famously ordered his ships to "Damn the torpedoes!"
nd sailed into the bay's heavily fortified mouth. Farragut captured the ironclad to claim victory in the war's last major naval battle; the two red-brick forts that bombarded his fleet still flank the route to the Gulf.
George Crozier, who runs the Dauphin Island Sea Lab, hasn't heard of a better idea than the gates for protecting today's Mobile Bay, which has more than 80 miles of coast lined with wetlands and marshes that provide homes for birds, fish, shrimp and other wildlife.
"If they build what is essentially a wall across the bay and put a gate in it, that's the first thing I've heard of that even has a chance to work," Crozier said.