It may seem crazy, but as we saw during Hurricane Harvey, many people were out of drinking water during a flood. The problem is that the water that is available is too contaminated to drink.
There are many issues with floodwater that make it undrinkable. The primary offender is sewage. As the floods fill the sewage systems, that waste enters the floodwaters.
Additional issues come from chemical contamination. Flooded gas tanks, household chemicals, pesticides, and mining or construction chemicals can all find their way into floodwaters.
Any of these issues would be enough to make you sick, but the combination is downright deadly.
Don’t dehydrate while surrounded by water!
If the diseases inherent in the sewage were the only problem, heat or chemical purification would be sufficient. This would kill bacteria that cause these diseases such as Vibrio cholerae that causes Cholera and Salmonella enterica serotype Typhi that causes Typhoid Fever.
Unfortunately, neither heat nor chemical treatments will make floodwaters safe to drink. The dangerous chemicals in these waters may only become more deadly if treated with heat or more chemicals. Heating the water will cause evaporation, which will increase the ratio of contaminants to water, making each sip even more dangerous.
Worse yet, mixing chemicals like bleach with your water may create chemical reactions further contaminating your drinking water. Bleach is a good option for fresh water sources that may have bacteria or viruses. However, when dealing with potential chemical threats, it doesn’t make sense to add more chemicals.
There are some solutions…
One option is to create a still. They can be created in a variety of ways, from underground stills that extract the moisture from the soil and air to stovetop stills that capture the vapor from boiling water. An underground still simply isn’t going to work in a flooded environment.
A stovetop still may work, however. You simply need to place a coffee mug or something to catch drinking water inside of a pot of contaminated water. Turn the lid for the pot upside-down and bring the water to a heavy steam or light boil. The water will evaporate and condense on the lid. The condensation will then run into the cup in the center of the pot.
There may be some chemicals in the water that have a similar boiling point, such as propanol, that may enter your clean water using this method. Propanol has a boiling temperature of 207 degrees Fahrenheit, just short of water’s 212. To avoid these chemicals, you can take the extra step of bringing the water to a boil before placing the inverted lid on the pot.
While this method will clean the water, it’s not ideal. It assumes you have some way to cook the water. This means a working stove, a pot with a lid, and a coffee mug. It is also a very slow method for purifying water.
The best solution is to have a great water filter. Most high-quality water filters will take care of bacteria, viruses, and chemicals. They also work on the spot. No need to wait for cooking or natural evaporation.
Even today, nearly three weeks later, many residents of Florida are still under a Boil Water Notice from Hurricane Irma. You can check FloridaHealth.Gov for details on your particular area.