Non-potable references the level of cleanliness, or lack there of, of water. When the word "non-potable" is used they are referencing that the water is undrinkable and should not to be consumed by humans. Meaning the water should not be drank, cooked with (aka in pots), or used for sanitary purposes; as the water is contaminated enough to be hazardous to humans.
Also known as: unpotable or simply, undrinkable.
What Causes Water to Become Non-Potable?
Storms and other natural & even man-made disasters can cause pipes to leak or break, or contaminate our water reservoirs. When our ground water or our local reservoirs are compromised they become non-potable until filtration or purification methods are used before consumption.
Post disaster, stay informed with you local news and sewer & sanitation company. These resources will be the first to alert you of water contamination notices. You local authorities will either provide safe water pickup locations and/or release a notice that a boil water warning has gone into effect until the damage can be repaired.
The best way to be prepared for a non-potable water emergency is to always have a well stocked inventory of clean drinkable water.
Additionally, you can have filtration methods ready like LifeStraws, chlorine or bleach drops, and more. Knowing purification methods will also come handy, like knowing how to boil contaminated water or desalinate water using heat of you find yourself only having salt water near by.