Draining New Orleans Official Says Flood Water to Hit Lake Pontchartrain Will Hurt

Lake Pontchartrain will have to take a hit to drain flood waters from metro New Orleans.

That’s how Carlton Dufrechou, executive director of the Lake Pontchartrain Basin Foundation, assessed the situation Thursday.

“Long-term effects will be negligible; near-term effects will be terrible. But the lake will recover,” Dufrechou said.

The lake will have to absorb everything – bacteria, chemicals and other contaminants, both natural and man-made – that remains in the flood water, Dufrechou said.

Other environmental engineers agree.

The biggest initial problem, said Don Blancher with Toxicological and Environmental Associates Inc. in Mobile, Ala., will be lack of oxygen.

“We may see fish kills,” Blancher, a New Orleans native, said.

As organic materials pass through the lake, they will absorb the oxygen, preventing the living creatures from getting the oxygen they need.

“But I don’t think there’s any other practical way to get the water out of New Orleans,” Blancher said.

There might be ways to direct the water through vegetated areas, such as City Park, that would naturally filter some of the contaminants and debris, but that may not be practical, Blancher said.

Right now, the most dangerous toxins in the water include human waste and decaying organic matter.

The more serious long-term effects are contaminants, such as petroleum, lead, mercury and cadmium.

Eventually, though, Blancher said, the lake will recover itself through natural cleansing systems.

Len Bahr, director of applied research at the Governor’s Office of Coastal Activities, said the only alternatives to pumping the water into Lake Pontchartrain are not practical.

If there were more time and more resources, he said, one option would be to collect the water in tanks and remove it to landfills.

“That’s pie in the sky. The sooner it’s pumped out, the less concentrated the contaminants. The faster, the better,” Bahr said.

Reports from the U.S. Environmental Protection Agency show that the toxicity levels of the water are dangerous for humans even to stand in, making it urgent to get the water out of the city.

Flood waters in New Orleans contain levels of sewage-related bacteria that are at least 10 times higher than acceptable safety limits, endangering rescue workers and remaining residents who even walk in it, federal officials said Wednesday.

Results of the first round of testing by the EPA were no surprise, but reinforced warnings that everyone still in the city take precautions to avoid getting the water on their skin – especially into cuts or other open wounds – much less in their mouths.

“Human contact with the flood water should be avoided as much as possible,” EPA Administrator Stephen L. Johnson said.

Health hazards from that water make it imperative that remaining residents comply with evacuation orders, added Dr. Julie Gerberding, director of the U.S. Centers for Disease Control and Prevention.

“If you haven’t left the city yet, you must do so,” she said.

Also found were elevated levels of brain-harming lead, a risk if people, particularly children, were to drink the water, something residents have been told to avoid since Hurricane Katrina struck.

The first tests for more than 100 chemicals and other pollutants so far turned up elevated levels only of E. coli and other coliform bacteria – markers for sewage contamination – and lead.

But, “we don’t know what else is contained in that water,” Johnson warned.

The first testing was done on water from residential neighborhoods, not industrial sites where other toxic contaminants may lurk. Moreover, oil is in the water, and it’s likely that chemicals such as asbestos will be in debris from older buildings, he said.

Wednesday’s initial focus was on standing flood water, but more than 1,000 drinking water systems in Mississippi, Louisiana and Alabama were affected by the hurricane. EPA testing is going on in the other states, too, and how quickly drinking water can be restored in part depends on the degree of contamination in water supplies those systems treat.

Each water-treatment plant will have to adjust levels of chlorine, filtration and other treatments to eliminate pathogens, such as E. coli bacteria or the parasite cryptosporidium, says water quality expert Charles O’Melia of Johns Hopkins University.

If chemicals are in water supplies as well, it’s possible activated carbon could soak them up, he said; routine treatment would remove the carbon.

Many hurricane-stricken areas have issued boil-water alerts, and boiling will kill bacteria and parasites, O’Melia said. The CDC recommends a rolling boil for one minute; some health experts recommend the additional step of running the water through coffee filters.

All the engineers and ecologists agreed though that there are lots of unknowns. Some problems won’t be apparent until the drainage is complete.

“We’ll know more once there’s data. But the need to get rid of water outweighs any long-term effects,” said Brad Droy, president and CEO of Toxicology and Environmental Associates Inc. in Baton Rouge.

The Associated Press contributed to this report.