Harvey Floodwaters Still Pose Significant Health Threat, Testing Shows

Pam Wright
Published: September 13, 2017

It's been nearly three weeks since Harvey hovered over south Texas, dumping historic amounts of rain that left Houston and the surrounding region flooded for weeks. Waters have receded in most places but what remains contains toxic levels of contaminants, new tests reveal.

Testing of floodwaters organized by the New York Times and conducted by Baylor College of Medicine and Rice University indicates that some Houston neighborhoods have dangerous levels of harmful contaminants, including lead, arsenic and bacteria like E. coli.

In one apartment complex along Houston's Buffalo Bayou, levels of E. coli, which comes from fecal matter, were tested in one kitchen at levels 135 times what is considered safe.

 “There’s pretty clearly sewage contamination, and it’s more concentrated inside the home than outside the home,” Lauren Stadler, an assistant professor of civil and environmental engineering at Rice University, told the New York Times.

Some Houston residents who have returned to their homes have reported a stench in the air that made them feel sick.

Brad Greer, 49, said he became ill after developing infections on both of his legs. After a course of antibiotics failed to halt the infection, Greer was taken to the emergency room at Houston Methodist for an intravenous drip and more antibiotics. Stories like his are common. 

The team that tested the waters warn residents to refrain from wading through waters and to take precautions.

“If people have bad headaches, respiratory problems, swelling of a limb or a bad rash, go see a doctor right away,” Winifred Hamilton, the environmental health service director at Baylor College of Medicine, told the New York Times. “Don’t assume it will go away on its own.”

Mold is another concern, the team said.

“Mold is taking off all over the city,” Winifred Hamilton, director of the Environmental Health Service at Baylor College of Medicine and a member of the testing group, told the Times. “People with allergies or asthma are particularly sensitive to it. If people have bad headaches, respiratory problems, swelling of a limb or a bad rash, go see a doctor right away. Don’t assume it will go away on its own.’’

(MORE: Irma's Staggering Toll)

Hamilton said people should wear a mask, goggles, gloves and rubber boots as they try to clean and repair their houses.

"II would change my clothes immediately after leaving the house, and put them in the wash with nothing else," she said, noting that children should be watched carefully.

“We have a lot of what looks like sand, like something you might want to make a castle of,” she said. “But this is not clean sand, this is sludge sediment.”

“Don’t let your children play in sediment from the flood. We don’t want children playing in lead.”


The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

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