NEW ORLEANS — The first of 200 ships idled by a massive oil spill began crawling down the Mississippi River Friday after the Coast Guard reopened the waterway to traffic, but it could be days before all of the ships are cleared.

A 100-mile stretch of the river has been shut down since Wednesday, when a barge split open in a collision with the Liberian-flagged tanker Tintomara. Roughly 419,000 gallons spilled into the fast-flowing waterway to commerce, and crews have sopped up about 11,000 — just a fraction of what the barge was carrying.

The first ship to leave the mouth of the river, the Overseas New York, is bound for refineries upriver from New Orleans, said Coast Guard Capt. Lincoln Stroh. Ships will move based on economic priorities, Stroh said. The Mississippi between New Orleans and Baton Rouge is dotted with oil refineries and huge grain operations.

A cleaning station was set up near the mouth of the river to scrub the hulls of vessels heading into the Gulf Of Mexico as they sail through the oil sheen that extended south from New Orleans. The ships are scrubbed to avoid further contamination.

Barges carrying grain south from the American heartland and a 2,000-passenger cruise ship were among vessels affected by the closure. Carnival Corp. said its Carnival Fantasy liner, due in New Orleans Saturday, was diverted to Mobile, Ala. Passengers would be bused to New Orleans.

The shutdown could cost shippers millions of dollars in lost commerce, said John Hyatt, vice president of Irwin Brown Co., a New Orleans-based freight forwarder.

State authorities were optimistic environmental damage could be contained. Divers were inspecting the barge, which is wedged against the Mississippi River bridge. Officials said they believe little fuel is left, and say they don't think it is a danger to navigation or a hazard to the structure of the bridge.

The spill was the largest since a tanker ran aground in 2000 about 40 miles south of New Orleans, dumping more than half a million gallons of crude oil on the Mississippi. That spill closed about 26 miles of the river. Authorities are investigating the cause of the crash, and said there wasn't a properly licensed pilot aboard the tugboat towing the barge.

It wasn't clear how much cleanup would cost, or what the economic impact on commerce will be. John Hyatt, vice president of Irwin Brown Co., a New Orleans-based freight forwarder, said he expected the total impact on shippers and receivers would quickly climb into many millions of dollars.

Also Friday, residents sued the owners and operators of the vessels that collided, alleging in U.S. district court that they have been exposed to fumes from the fuel oil wafting off the river.

A fuel odor hung in the air in the French Quarter and Algiers areas Wednesday and Thursday. By Friday, morning diners at the Cafe du Monde near the French Quarter riverfront were sipping coffee, and the aroma of New Orleans' signature beignets, a fried and sugar-powdered pastry, had replaced the fuel smell.

Still, ferries and the riverboats Natchez and Creole Queen, which carry tourists on daily tours along the river, awaited Coast Guard approval to sail.

"There's a lot of disappointed people," said Jamie Messersmith, manager for the Natchez steamboat. "One couple was married on the Natchez and they came for their anniversary," he said.