Extreme rainfall and flooding from Hurricane Harvey has left thousands in Houston and surrounding communities stranded. Some parts of the city have experienced over 100cm of rain, and forecasters say that number is expected to rise over the coming days. This morning the storm repositioned itself in the Gulf of Mexico, where it will collect more moisture before striking land again. When it does, some areas of Texas and Louisiana could see an additional 51cm of rain. On top of all this, flash flood warnings are still in effect.
Floodwaters pose many immediate threats to people, animals and property. According to reporting by the Washington Post, officials warn that roughly 30,000 people will be forced from their homes across Texas and Louisiana. But there are less obvious and equally dangerous health risks associated with floodwater — including exposure to potentially harmful chemicals. Some Houston residents are already reporting an "unbearable" chemical smell in certain areas that could be related to the city's oil refineries, gas facilities and chemical plants.
There is a thick smell of oil in the air downtown #Houston
— Rhonda Ragsdale (@profragsdale) August 27, 2017
Renee Funk, Emergency Management Director at the US Centres for Disease Control, told Gizmodo that folks who come into contact with floodwaters must take precautions to make sure they aren't impacted by anything the floodwaters might have dredged up, from weed repellent to animal faeces.
"Chemicals can certainly be in the water," she said. "A lot of times, people keep pesticides in their garages. When that floods, those containers are floating down the street and so if people come into floodwaters at all, they need to shower and wash their hands and get it off of them as soon as possible."
There's also a risk of carbon monoxide poisoning from generators left on in garages. Funk said this is tragically common in any extreme flooding situation.
"Initially in this phase of active flooding... we're concerned about carbon monoxide poisoning from portable generators," she explained. "The floodwaters lead to power outages and unfortunately, there will be people who die from this kind of poisoning I'm sure."
The public health situation with regard to floodwater is so serious that public health officials in Texas are urging Houston-area residents to get Tetanus shots immediately, according to NPR. Faecal matter floating in flood water could easily infect wounds and pose other threats to people who drink water out of desperation. Gizmodo reached out to the Texas Department of State Health Services and Houston's Public Health Department for more information but had not heard back at time of writing.
In some cases, standing water can also pose a risk for insect-borne illnesses, as it can act as a breeding ground for mosquitoes. But Funk says that isn't an immediate threat.
"Initially, the flooding helps wash away the mosquito larvae and so it will take a couple of weeks for mosquitos to come back," she said. "At that point, there will need to be some mosquito control."
While the end of this cataclysmic storm is finally in sight, the next few days will undoubtedly be hell, especially for the thousands of folks still seeking rescue. For more information on how to stay safe after a hurricane, you can check out the CDC's resources here. If you are in Texas and seeking medical attention due to the storm, you can find help here.