Mandatory evacuation - how dangerous is the water?

EPA Ground Water & Drinking Water > E. coli 0157:H7 in drinking water :

"One of hundreds of strains of the bacterium Escherichia coli, E. coli O157:H7 is an emerging cause of foodborne and waterborne illness. Although most strains of E. coli are harmless and live in the intestines of healthy humans and animals, this strain produces a powerful toxin and can cause severe illness. E. coli O157:H7 was first recognized as a cause of illness during an outbreak in 1982 traced to contaminated hamburgers. Since then, most infections are believed to have come from eating undercooked ground beef.

"However, some have been waterborne. In 1999, people became sick after drinking contaminated water in Washington County, New York and swimming in contaminated water in Clark County, Washington."

On another page at the EPA website setting forth limits for various contaminants, it states that E. coli is not per se a health risk but is used as a flag to alert water suppliers and regulators that contamination with human and/or animal waste is likely to have occurred which would entail the risk of contamination by yet other organisms which are dangerous.

The lack of details on the "contaminants" in the water just might cause a person of the paranoid persuasion to question whether there really is that much danger. Perhaps the danger is being oversold to encourage "voluntary" evacuation of the remaining residents.

This sort of suspicion is reinforced by the way the authorities are playing up the five deaths (four of them in Mississippi) from an apparent water-borne infection. After all, that microbe is unrelated to E. coli, does not come from humans but is present in the water naturally, and typically kills 12 people a year in the Gulf region even without the stress of a hurricane.

Another piece of the puzzle that doesn't fit is the EPA's statement that infections of E. coli 0157:H7 (the dangerous form of E. coli) usually present symptoms in 2 to 4 days, but no more than 8 days. By that logic, the peak of infection should already have passed for those who have chosen to stay in N.O.

For once in this mess, Gov. Blanco may be right, perhaps it would be prudent to await the results of detailed water testing before proceeding with the mayor's plan to use force to dispossess citizens of their property.