TORONTO - The powerful hurricane, with a storm surge of waters topping six metres, flooded an estimated 230,000 square kilometres in the southern U.S. states of Louisiana, Mississippi and Alabama on August 29.

Katrina altered coastlines, wiped out fisheries, destroyed 1.75 million hectares of timber and left a toxic mess of oil spills and waste in the city of New Orleans and many other places.

"It's been impossible to get people on the ground in order to assess the extent of the damage," said Clint Jeske, a wildlife biologist at National Wetlands Research Centre, based in Lafayette, Louisiana.

Until recently, all available boats and aircraft were involved in rescue efforts, and now security and safety concerns have restricted access, Jeske told Tierramérica.

However, satellite photos reveal that at least 52 square km of coastal wetlands and a number of offshore barrier islands in the Gulf of Mexico have entirely disappeared. Some of the barrier islands are wildlife refuges and important bird areas, especially for neo-tropical migrating species that spend the northern hemisphere autumn and winter in Mexico, Central America and South America.

"Shorebirds were on their way south. They probably took a huge hit from the storm," Jeske said.

In flooded New Orleans there is hardly a bird left alive. The few that Jeske saw while involved in evacuation efforts last week were "all beat up".

"It was really strange to see a pigeon falling out the sky into the water," he said. Any surviving birds are starving or sick from drinking the polluted floodwaters, he said.

Millions of litres of New Orleans' contaminated floodwaters are being pumped into nearby Lake Pontchartrain with the full knowledge it will damage marine life. Louisiana's Department of Environment says it expects large numbers of fish to die but fully supports the pumping.

Lake Pontchartrain is actually a huge estuary that opens directly into the Gulf of Mexico, so there are fears that contaminants will hurt the marine life in the Gulf.

New Orleans is not only a major port and supplier of 30 percent of seafood to the United States, it is one the world's largest oil and petro-chemical centres.

With about 140 large refineries and chemical plants, the area is responsible for nearly 30 percent of U.S. oil, 20 percent of its natural gas and a large percentage of chemicals, including fertilisers.

"You couldn't pick a worse place to be hit by a major hurricane," said Alan Covich, director of the Institute of Ecology at the University of Georgia.

Katrina was an exceptional hurricane with powerful winds and an enormous storm surge, said Covich who has studied the effects of hurricanes on the environment.

"There's been no storm of this scale in the United States before," Covich told Tierramérica.

The U.S. Coast Guard has said that 26 large oil drilling platforms in the Gulf of Mexico were missing and about another 20 had sustained damage.

An unknown number of refineries and chemical plants, storage tanks and shipping containers were damaged, along with many thousands of kilometres of oil and gas pipelines.

Two major oil spills have been identified so far. A 13.5-million-litre spill from leaking refinery storage tanks contaminates much of the town of Chalmette and surrounding wetlands.

Another set of ruptured storage tanks at the mouth of the Mississippi River has dumped an estimated 12 million litres of crude oil into the surrounding wetlands and Gulf according to the Louisiana Department of Environment.

There are likely other spills of oil, gasoline, diesel and chemicals throughout the region, but until all the floodwaters are gone it will be impossible to verify.

Unfortunately, most scientists are being prevented by the military patrolling the hurricane-damaged area from investigating on their own, Covich said.

Officials at the U.S. Environmental Protection Agency (EPA) have done limited water sampling and not found contaminants in New Orleans floodwaters other than very high levels of lead and bacteria.

That result surprises most experts -- and the EPA stresses that the data is preliminary.

The agency is under criticism for taking two weeks to release those results and for not making public the many damage and spill reports it received from oil and chemical companies.

"I'm surprised the EPA is not doing more," said Covich. "The economic recovery is tied to the ecological recovery of the region."

He worries the federal government is failing to take the lead in a prompt scientific assessment of the environmental issues.

"There are a huge range of environmental impacts from the storm," says David Shaw, director of the GeoResources Institute at Mississippi State University.

While Mississippi does not have as much floodwater as low-lying Louisiana, it took the worst of the storm surge, which has left piles of debris four metres high all along its coast.

"Disposing of the debris is a major problem," Shaw told Tierramérica. Burning debris has been banned because of an ongoing drought and the millions of downed trees.

Beaches are gone, a thick layer of mud covers everything for several kilometres inland and much of the groundwater is contaminated, either by salt or bacteria, he said.

Fish kills have been reported in lakes and rivers and the entire fishery along the Gulf may have been wiped out. Boats and ports were destroyed along with shrimp and oyster beds.

"We will feel the effects of this storm for another 15 years," Shaw said.

(*Stephen Leahy is an IPS correspondent. Originally published Sep. 17 by Latin American newspapers that are part of the Tierramérica network. Tierramérica is a specialised news service produced by IPS with the backing of the United Nations Development Programme and the United Nations Environment Programme.)

Copyright 2005 IPS-Inter Press Service

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