( CNN ) -- The U.S. Coast Guard closed 98 miles of the Mississippi River from New Orleans , Louisiana , southward after a fuel barge and a tanker collided early Wednesday , spilling more than 400,000 gallons of fuel oil . Coast Guard personnel try to contain a fuel oil spill in the Mississippi River in New Orleans on Wednesday . The closure -- on what is a major shipping route between the Midwest and the Gulf of Mexico -- could last days , and the cleanup could take weeks , said Capt . Lincoln Stroh , the Coast Guard chief in New Orleans . The collision between the Liberian-flagged chemical tanker Tintomara and the barge pushed by the tug Mel Oliver happened about 1:30 a.m. Wednesday , splitting the barge nearly in half and dumping more than 419,000 gallons of oil into the river , the Coast Guard said . The accident happened just north of the massive bridges connecting downtown New Orleans to the west bank of the Mississippi , the Coast Guard said . The tanker was undamaged . See a map of where the spill happened » . The Coast Guard said Wednesday evening that the tug had no properly licensed crew on board at the time of the collision . No injuries were reported , and the National Transportation Safety Board said it has dispatched investigators to look into the accident . The accident left a sheen of oil over much of the river and its banks . Booms were deployed to contain the oil , and skimmers are being used to suck it off the surface , said Petty Officer Thomas Blue , a Coast Guard spokesman . Watch scenes from the oil spill » . The spill is much smaller than the ones that followed Hurricane Katrina in 2005 , when the Coast Guard estimated that more than 7 million gallons of oil were dumped into the Mississippi and nearby waterways . But Wilma Subra , a chemist who advises the Louisiana Environmental Action Network , said the oil could affect wildlife and work its way up the food chain into residents , many of whom fish for subsistence . `` This is a spill that occurred in a very urban area , and it can impact a very large number of people , '' she said . The oil , widely used as marine fuel , is heavier than diesel but lighter than crude , and it is likely to stick to rocks , trees and wildlife , Stroh said . `` Some will evaporate with sunlight , but there will be residuals in the waterway which need to be cleaned up , '' he said . However , State Department of Environmental Quality officials said the oil is so thick that it could sink , which would complicate the cleanup , the Times-Picayune of New Orleans reported . The Mississippi is the primary source of drinking water for the region , and workers have deployed booms around intakes for local water systems , said Paul Book , the head of the cleanup effort for barge owners American Commercial Lines . Water intakes in the oil spill area -- those for Algiers , Gretna , St. Bernard Parish and Plaquemines Parish -- were closed to prevent contamination , though residents there still could get water through their taps because of reserve supplies , the Times-Picayune reported . A swifter-than-normal current quickly drew the slick downstream . The Coast Guard initially closed 29 miles of the river but expanded that to 98 miles by Wednesday evening , the service said . The heavy , sticky oil left a `` real strong '' smell hanging over much of downtown New Orleans , said Carl Bauder , who runs a barber shop near the foot of Canal Street . The Coast Guard 's closure of traffic shut down commuter ferries across the river , said Bauder , who lives in the West Bank neighborhood of Algiers . `` [ The oil has ] done a lot of damage to our Moonwalk area and down by the aquarium , '' he said . Department of Environmental Quality officials said they did n't believe breathing the air near the river would be a problem , adding that emergency personnel were checking the air with portable monitors and had n't found dangerous hydrocarbon levels , the Times-Picayune reported . New Orleans is among the largest U.S. ports . More than 30 ships were queued early Wednesday afternoon , waiting to pass through the closed zone , Coast Guard spokeswoman Jaclyn Young said . Ships approaching the mouth of the river from the Gulf of Mexico were being asked to stay out , Stroh said .
Ninety - eight miles of Mississippi River closed from New Orleans southward . Flood could last days , but cleanup could take weeks , Coast Guard says . More than 400,000 gallons of crude oil spilled after barge , barge collide . River is major route for cargo between Midwest , Gulf of Mexico .