But still people worry.
“Nobody’s washing their faces in the showers anymore. Nobody’s drinking the water,” Angela Miller of Violet said during a break Thursday outside the Chalmette hair salon where she works. “My neighbor has a pool that they have emptied. And they have no water in there now until this matter is cleared up.”
That’s not necessary, experts say. Stomach acids, boiling and chlorine all will kill the amoeba.
Many people think water should test free of the amoeba before they use it, DHH said, but testing tap water for the amoeba is not as important as making sure that it holds enough chlorine to kill the creature.
Last Friday — the latest available report — there was no detectable free chlorine in water mains and other testing stations along nearly two-thirds the length of the long, narrow parish.
To get the recommended level of one-half part chlorine per million at the system’s outer reaches, the parish has been putting about eight times that amount into the water at its treatment plant, said Jake Causey, chief engineer for the state Office of Public Health’s engineering services section.
Investigators may never know just how Naegleria got into the pipes.
It usually lives just above the bottom of fresh water, feeding on bacteria. It spreads farthest in warm water. Minnesota reported two infections in the past few years, but the vast majority have been in 15 Southern states, with more than half the total in Florida and Texas.
It might have entered and survived in the water system in many ways, including Hurricane Katrina in 2005 and population loss since then, Causey said.
The parish had to repair more than 1,000 broken pipes after floodwaters receded, he said. “When it was brought back online, the water was chlorinated, flushed and sampled. But water mains can build up biofilms over time, and can get microorganisms in there that stay behind the biofilm.”